3845 строки
90 KiB
C
3845 строки
90 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* f_fs.c -- user mode file system API for USB composite function controllers
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*
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* Copyright (C) 2010 Samsung Electronics
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* Author: Michal Nazarewicz <mina86@mina86.com>
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*
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* Based on inode.c (GadgetFS) which was:
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* Copyright (C) 2003-2004 David Brownell
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* Copyright (C) 2003 Agilent Technologies
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*/
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/* #define DEBUG */
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/* #define VERBOSE_DEBUG */
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#include <linux/blkdev.h>
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#include <linux/pagemap.h>
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#include <linux/export.h>
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#include <linux/fs_parser.h>
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#include <linux/hid.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/scatterlist.h>
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#include <linux/sched/signal.h>
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#include <linux/uio.h>
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#include <linux/vmalloc.h>
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#include <asm/unaligned.h>
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#include <linux/usb/ccid.h>
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#include <linux/usb/composite.h>
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#include <linux/usb/functionfs.h>
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#include <linux/aio.h>
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#include <linux/mmu_context.h>
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#include <linux/poll.h>
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#include <linux/eventfd.h>
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#include "u_fs.h"
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#include "u_f.h"
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#include "u_os_desc.h"
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#include "configfs.h"
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#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
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/* Reference counter handling */
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static void ffs_data_get(struct ffs_data *ffs);
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static void ffs_data_put(struct ffs_data *ffs);
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/* Creates new ffs_data object. */
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static struct ffs_data *__must_check ffs_data_new(const char *dev_name)
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__attribute__((malloc));
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/* Opened counter handling. */
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static void ffs_data_opened(struct ffs_data *ffs);
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static void ffs_data_closed(struct ffs_data *ffs);
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/* Called with ffs->mutex held; take over ownership of data. */
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static int __must_check
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__ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
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static int __must_check
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__ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
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/* The function structure ***************************************************/
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struct ffs_ep;
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struct ffs_function {
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struct usb_configuration *conf;
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struct usb_gadget *gadget;
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struct ffs_data *ffs;
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struct ffs_ep *eps;
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u8 eps_revmap[16];
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short *interfaces_nums;
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struct usb_function function;
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};
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static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
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{
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return container_of(f, struct ffs_function, function);
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}
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static inline enum ffs_setup_state
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ffs_setup_state_clear_cancelled(struct ffs_data *ffs)
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{
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return (enum ffs_setup_state)
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cmpxchg(&ffs->setup_state, FFS_SETUP_CANCELLED, FFS_NO_SETUP);
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}
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static void ffs_func_eps_disable(struct ffs_function *func);
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static int __must_check ffs_func_eps_enable(struct ffs_function *func);
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static int ffs_func_bind(struct usb_configuration *,
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struct usb_function *);
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static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
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static void ffs_func_disable(struct usb_function *);
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static int ffs_func_setup(struct usb_function *,
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const struct usb_ctrlrequest *);
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static bool ffs_func_req_match(struct usb_function *,
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const struct usb_ctrlrequest *,
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bool config0);
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static void ffs_func_suspend(struct usb_function *);
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static void ffs_func_resume(struct usb_function *);
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static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
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static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
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/* The endpoints structures *************************************************/
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struct ffs_ep {
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struct usb_ep *ep; /* P: ffs->eps_lock */
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struct usb_request *req; /* P: epfile->mutex */
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/* [0]: full speed, [1]: high speed, [2]: super speed */
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struct usb_endpoint_descriptor *descs[3];
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u8 num;
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int status; /* P: epfile->mutex */
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};
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struct ffs_epfile {
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/* Protects ep->ep and ep->req. */
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struct mutex mutex;
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struct ffs_data *ffs;
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struct ffs_ep *ep; /* P: ffs->eps_lock */
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struct dentry *dentry;
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/*
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* Buffer for holding data from partial reads which may happen since
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* we’re rounding user read requests to a multiple of a max packet size.
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*
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* The pointer is initialised with NULL value and may be set by
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* __ffs_epfile_read_data function to point to a temporary buffer.
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*
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* In normal operation, calls to __ffs_epfile_read_buffered will consume
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* data from said buffer and eventually free it. Importantly, while the
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* function is using the buffer, it sets the pointer to NULL. This is
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* all right since __ffs_epfile_read_data and __ffs_epfile_read_buffered
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* can never run concurrently (they are synchronised by epfile->mutex)
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* so the latter will not assign a new value to the pointer.
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*
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* Meanwhile ffs_func_eps_disable frees the buffer (if the pointer is
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* valid) and sets the pointer to READ_BUFFER_DROP value. This special
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* value is crux of the synchronisation between ffs_func_eps_disable and
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* __ffs_epfile_read_data.
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*
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* Once __ffs_epfile_read_data is about to finish it will try to set the
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* pointer back to its old value (as described above), but seeing as the
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* pointer is not-NULL (namely READ_BUFFER_DROP) it will instead free
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* the buffer.
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*
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* == State transitions ==
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*
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* • ptr == NULL: (initial state)
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* ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP
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* ◦ __ffs_epfile_read_buffered: nop
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* ◦ __ffs_epfile_read_data allocates temp buffer: go to ptr == buf
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* ◦ reading finishes: n/a, not in ‘and reading’ state
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* • ptr == DROP:
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* ◦ __ffs_epfile_read_buffer_free: nop
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* ◦ __ffs_epfile_read_buffered: go to ptr == NULL
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* ◦ __ffs_epfile_read_data allocates temp buffer: free buf, nop
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* ◦ reading finishes: n/a, not in ‘and reading’ state
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* • ptr == buf:
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* ◦ __ffs_epfile_read_buffer_free: free buf, go to ptr == DROP
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* ◦ __ffs_epfile_read_buffered: go to ptr == NULL and reading
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* ◦ __ffs_epfile_read_data: n/a, __ffs_epfile_read_buffered
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* is always called first
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* ◦ reading finishes: n/a, not in ‘and reading’ state
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* • ptr == NULL and reading:
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* ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP and reading
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* ◦ __ffs_epfile_read_buffered: n/a, mutex is held
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* ◦ __ffs_epfile_read_data: n/a, mutex is held
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* ◦ reading finishes and …
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* … all data read: free buf, go to ptr == NULL
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* … otherwise: go to ptr == buf and reading
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* • ptr == DROP and reading:
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* ◦ __ffs_epfile_read_buffer_free: nop
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* ◦ __ffs_epfile_read_buffered: n/a, mutex is held
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* ◦ __ffs_epfile_read_data: n/a, mutex is held
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* ◦ reading finishes: free buf, go to ptr == DROP
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*/
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struct ffs_buffer *read_buffer;
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#define READ_BUFFER_DROP ((struct ffs_buffer *)ERR_PTR(-ESHUTDOWN))
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char name[5];
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unsigned char in; /* P: ffs->eps_lock */
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unsigned char isoc; /* P: ffs->eps_lock */
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unsigned char _pad;
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};
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struct ffs_buffer {
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size_t length;
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char *data;
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char storage[];
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};
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/* ffs_io_data structure ***************************************************/
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struct ffs_io_data {
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bool aio;
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bool read;
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struct kiocb *kiocb;
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struct iov_iter data;
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const void *to_free;
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char *buf;
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struct mm_struct *mm;
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struct work_struct work;
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struct usb_ep *ep;
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struct usb_request *req;
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struct sg_table sgt;
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bool use_sg;
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struct ffs_data *ffs;
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};
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struct ffs_desc_helper {
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struct ffs_data *ffs;
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unsigned interfaces_count;
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unsigned eps_count;
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};
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static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
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static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
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static struct dentry *
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ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
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const struct file_operations *fops);
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/* Devices management *******************************************************/
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DEFINE_MUTEX(ffs_lock);
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EXPORT_SYMBOL_GPL(ffs_lock);
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static struct ffs_dev *_ffs_find_dev(const char *name);
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static struct ffs_dev *_ffs_alloc_dev(void);
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static void _ffs_free_dev(struct ffs_dev *dev);
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static void *ffs_acquire_dev(const char *dev_name);
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static void ffs_release_dev(struct ffs_data *ffs_data);
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static int ffs_ready(struct ffs_data *ffs);
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static void ffs_closed(struct ffs_data *ffs);
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/* Misc helper functions ****************************************************/
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static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
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__attribute__((warn_unused_result, nonnull));
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static char *ffs_prepare_buffer(const char __user *buf, size_t len)
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__attribute__((warn_unused_result, nonnull));
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/* Control file aka ep0 *****************************************************/
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static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
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{
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struct ffs_data *ffs = req->context;
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complete(&ffs->ep0req_completion);
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}
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static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
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__releases(&ffs->ev.waitq.lock)
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{
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struct usb_request *req = ffs->ep0req;
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int ret;
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req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
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spin_unlock_irq(&ffs->ev.waitq.lock);
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req->buf = data;
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req->length = len;
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/*
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* UDC layer requires to provide a buffer even for ZLP, but should
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* not use it at all. Let's provide some poisoned pointer to catch
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* possible bug in the driver.
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*/
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if (req->buf == NULL)
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req->buf = (void *)0xDEADBABE;
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reinit_completion(&ffs->ep0req_completion);
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ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
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if (unlikely(ret < 0))
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return ret;
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ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
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if (unlikely(ret)) {
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usb_ep_dequeue(ffs->gadget->ep0, req);
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return -EINTR;
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}
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ffs->setup_state = FFS_NO_SETUP;
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return req->status ? req->status : req->actual;
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}
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static int __ffs_ep0_stall(struct ffs_data *ffs)
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{
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if (ffs->ev.can_stall) {
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pr_vdebug("ep0 stall\n");
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usb_ep_set_halt(ffs->gadget->ep0);
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ffs->setup_state = FFS_NO_SETUP;
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return -EL2HLT;
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} else {
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pr_debug("bogus ep0 stall!\n");
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return -ESRCH;
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}
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}
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static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
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size_t len, loff_t *ptr)
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{
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struct ffs_data *ffs = file->private_data;
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ssize_t ret;
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char *data;
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ENTER();
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/* Fast check if setup was canceled */
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if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
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return -EIDRM;
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/* Acquire mutex */
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ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
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if (unlikely(ret < 0))
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return ret;
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/* Check state */
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switch (ffs->state) {
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case FFS_READ_DESCRIPTORS:
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case FFS_READ_STRINGS:
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/* Copy data */
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if (unlikely(len < 16)) {
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ret = -EINVAL;
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break;
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}
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data = ffs_prepare_buffer(buf, len);
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if (IS_ERR(data)) {
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ret = PTR_ERR(data);
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break;
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}
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/* Handle data */
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if (ffs->state == FFS_READ_DESCRIPTORS) {
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pr_info("read descriptors\n");
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ret = __ffs_data_got_descs(ffs, data, len);
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if (unlikely(ret < 0))
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break;
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ffs->state = FFS_READ_STRINGS;
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ret = len;
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} else {
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pr_info("read strings\n");
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ret = __ffs_data_got_strings(ffs, data, len);
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if (unlikely(ret < 0))
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break;
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ret = ffs_epfiles_create(ffs);
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if (unlikely(ret)) {
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ffs->state = FFS_CLOSING;
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break;
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}
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ffs->state = FFS_ACTIVE;
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mutex_unlock(&ffs->mutex);
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ret = ffs_ready(ffs);
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if (unlikely(ret < 0)) {
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ffs->state = FFS_CLOSING;
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return ret;
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}
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return len;
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}
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break;
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case FFS_ACTIVE:
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data = NULL;
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/*
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* We're called from user space, we can use _irq
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* rather then _irqsave
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*/
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spin_lock_irq(&ffs->ev.waitq.lock);
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switch (ffs_setup_state_clear_cancelled(ffs)) {
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case FFS_SETUP_CANCELLED:
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ret = -EIDRM;
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goto done_spin;
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case FFS_NO_SETUP:
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ret = -ESRCH;
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goto done_spin;
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case FFS_SETUP_PENDING:
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break;
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}
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/* FFS_SETUP_PENDING */
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if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
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spin_unlock_irq(&ffs->ev.waitq.lock);
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ret = __ffs_ep0_stall(ffs);
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break;
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}
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/* FFS_SETUP_PENDING and not stall */
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len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
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spin_unlock_irq(&ffs->ev.waitq.lock);
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data = ffs_prepare_buffer(buf, len);
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if (IS_ERR(data)) {
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ret = PTR_ERR(data);
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break;
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}
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spin_lock_irq(&ffs->ev.waitq.lock);
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/*
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* We are guaranteed to be still in FFS_ACTIVE state
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* but the state of setup could have changed from
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* FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
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* to check for that. If that happened we copied data
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* from user space in vain but it's unlikely.
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*
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* For sure we are not in FFS_NO_SETUP since this is
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* the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
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* transition can be performed and it's protected by
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* mutex.
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*/
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if (ffs_setup_state_clear_cancelled(ffs) ==
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FFS_SETUP_CANCELLED) {
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ret = -EIDRM;
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done_spin:
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spin_unlock_irq(&ffs->ev.waitq.lock);
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} else {
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/* unlocks spinlock */
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ret = __ffs_ep0_queue_wait(ffs, data, len);
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}
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kfree(data);
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break;
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default:
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ret = -EBADFD;
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break;
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}
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mutex_unlock(&ffs->mutex);
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return ret;
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}
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/* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
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static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
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size_t n)
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__releases(&ffs->ev.waitq.lock)
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{
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/*
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* n cannot be bigger than ffs->ev.count, which cannot be bigger than
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* size of ffs->ev.types array (which is four) so that's how much space
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* we reserve.
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*/
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struct usb_functionfs_event events[ARRAY_SIZE(ffs->ev.types)];
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const size_t size = n * sizeof *events;
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unsigned i = 0;
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memset(events, 0, size);
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do {
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events[i].type = ffs->ev.types[i];
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if (events[i].type == FUNCTIONFS_SETUP) {
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events[i].u.setup = ffs->ev.setup;
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ffs->setup_state = FFS_SETUP_PENDING;
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}
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} while (++i < n);
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ffs->ev.count -= n;
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if (ffs->ev.count)
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memmove(ffs->ev.types, ffs->ev.types + n,
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ffs->ev.count * sizeof *ffs->ev.types);
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spin_unlock_irq(&ffs->ev.waitq.lock);
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mutex_unlock(&ffs->mutex);
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return unlikely(copy_to_user(buf, events, size)) ? -EFAULT : size;
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}
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static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
|
||
size_t len, loff_t *ptr)
|
||
{
|
||
struct ffs_data *ffs = file->private_data;
|
||
char *data = NULL;
|
||
size_t n;
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
/* Fast check if setup was canceled */
|
||
if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
|
||
return -EIDRM;
|
||
|
||
/* Acquire mutex */
|
||
ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
|
||
if (unlikely(ret < 0))
|
||
return ret;
|
||
|
||
/* Check state */
|
||
if (ffs->state != FFS_ACTIVE) {
|
||
ret = -EBADFD;
|
||
goto done_mutex;
|
||
}
|
||
|
||
/*
|
||
* We're called from user space, we can use _irq rather then
|
||
* _irqsave
|
||
*/
|
||
spin_lock_irq(&ffs->ev.waitq.lock);
|
||
|
||
switch (ffs_setup_state_clear_cancelled(ffs)) {
|
||
case FFS_SETUP_CANCELLED:
|
||
ret = -EIDRM;
|
||
break;
|
||
|
||
case FFS_NO_SETUP:
|
||
n = len / sizeof(struct usb_functionfs_event);
|
||
if (unlikely(!n)) {
|
||
ret = -EINVAL;
|
||
break;
|
||
}
|
||
|
||
if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
|
||
ret = -EAGAIN;
|
||
break;
|
||
}
|
||
|
||
if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
|
||
ffs->ev.count)) {
|
||
ret = -EINTR;
|
||
break;
|
||
}
|
||
|
||
/* unlocks spinlock */
|
||
return __ffs_ep0_read_events(ffs, buf,
|
||
min(n, (size_t)ffs->ev.count));
|
||
|
||
case FFS_SETUP_PENDING:
|
||
if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
|
||
spin_unlock_irq(&ffs->ev.waitq.lock);
|
||
ret = __ffs_ep0_stall(ffs);
|
||
goto done_mutex;
|
||
}
|
||
|
||
len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
|
||
|
||
spin_unlock_irq(&ffs->ev.waitq.lock);
|
||
|
||
if (likely(len)) {
|
||
data = kmalloc(len, GFP_KERNEL);
|
||
if (unlikely(!data)) {
|
||
ret = -ENOMEM;
|
||
goto done_mutex;
|
||
}
|
||
}
|
||
|
||
spin_lock_irq(&ffs->ev.waitq.lock);
|
||
|
||
/* See ffs_ep0_write() */
|
||
if (ffs_setup_state_clear_cancelled(ffs) ==
|
||
FFS_SETUP_CANCELLED) {
|
||
ret = -EIDRM;
|
||
break;
|
||
}
|
||
|
||
/* unlocks spinlock */
|
||
ret = __ffs_ep0_queue_wait(ffs, data, len);
|
||
if (likely(ret > 0) && unlikely(copy_to_user(buf, data, len)))
|
||
ret = -EFAULT;
|
||
goto done_mutex;
|
||
|
||
default:
|
||
ret = -EBADFD;
|
||
break;
|
||
}
|
||
|
||
spin_unlock_irq(&ffs->ev.waitq.lock);
|
||
done_mutex:
|
||
mutex_unlock(&ffs->mutex);
|
||
kfree(data);
|
||
return ret;
|
||
}
|
||
|
||
static int ffs_ep0_open(struct inode *inode, struct file *file)
|
||
{
|
||
struct ffs_data *ffs = inode->i_private;
|
||
|
||
ENTER();
|
||
|
||
if (unlikely(ffs->state == FFS_CLOSING))
|
||
return -EBUSY;
|
||
|
||
file->private_data = ffs;
|
||
ffs_data_opened(ffs);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int ffs_ep0_release(struct inode *inode, struct file *file)
|
||
{
|
||
struct ffs_data *ffs = file->private_data;
|
||
|
||
ENTER();
|
||
|
||
ffs_data_closed(ffs);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
|
||
{
|
||
struct ffs_data *ffs = file->private_data;
|
||
struct usb_gadget *gadget = ffs->gadget;
|
||
long ret;
|
||
|
||
ENTER();
|
||
|
||
if (code == FUNCTIONFS_INTERFACE_REVMAP) {
|
||
struct ffs_function *func = ffs->func;
|
||
ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
|
||
} else if (gadget && gadget->ops->ioctl) {
|
||
ret = gadget->ops->ioctl(gadget, code, value);
|
||
} else {
|
||
ret = -ENOTTY;
|
||
}
|
||
|
||
return ret;
|
||
}
|
||
|
||
static __poll_t ffs_ep0_poll(struct file *file, poll_table *wait)
|
||
{
|
||
struct ffs_data *ffs = file->private_data;
|
||
__poll_t mask = EPOLLWRNORM;
|
||
int ret;
|
||
|
||
poll_wait(file, &ffs->ev.waitq, wait);
|
||
|
||
ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
|
||
if (unlikely(ret < 0))
|
||
return mask;
|
||
|
||
switch (ffs->state) {
|
||
case FFS_READ_DESCRIPTORS:
|
||
case FFS_READ_STRINGS:
|
||
mask |= EPOLLOUT;
|
||
break;
|
||
|
||
case FFS_ACTIVE:
|
||
switch (ffs->setup_state) {
|
||
case FFS_NO_SETUP:
|
||
if (ffs->ev.count)
|
||
mask |= EPOLLIN;
|
||
break;
|
||
|
||
case FFS_SETUP_PENDING:
|
||
case FFS_SETUP_CANCELLED:
|
||
mask |= (EPOLLIN | EPOLLOUT);
|
||
break;
|
||
}
|
||
case FFS_CLOSING:
|
||
break;
|
||
case FFS_DEACTIVATED:
|
||
break;
|
||
}
|
||
|
||
mutex_unlock(&ffs->mutex);
|
||
|
||
return mask;
|
||
}
|
||
|
||
static const struct file_operations ffs_ep0_operations = {
|
||
.llseek = no_llseek,
|
||
|
||
.open = ffs_ep0_open,
|
||
.write = ffs_ep0_write,
|
||
.read = ffs_ep0_read,
|
||
.release = ffs_ep0_release,
|
||
.unlocked_ioctl = ffs_ep0_ioctl,
|
||
.poll = ffs_ep0_poll,
|
||
};
|
||
|
||
|
||
/* "Normal" endpoints operations ********************************************/
|
||
|
||
static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
|
||
{
|
||
ENTER();
|
||
if (likely(req->context)) {
|
||
struct ffs_ep *ep = _ep->driver_data;
|
||
ep->status = req->status ? req->status : req->actual;
|
||
complete(req->context);
|
||
}
|
||
}
|
||
|
||
static ssize_t ffs_copy_to_iter(void *data, int data_len, struct iov_iter *iter)
|
||
{
|
||
ssize_t ret = copy_to_iter(data, data_len, iter);
|
||
if (likely(ret == data_len))
|
||
return ret;
|
||
|
||
if (unlikely(iov_iter_count(iter)))
|
||
return -EFAULT;
|
||
|
||
/*
|
||
* Dear user space developer!
|
||
*
|
||
* TL;DR: To stop getting below error message in your kernel log, change
|
||
* user space code using functionfs to align read buffers to a max
|
||
* packet size.
|
||
*
|
||
* Some UDCs (e.g. dwc3) require request sizes to be a multiple of a max
|
||
* packet size. When unaligned buffer is passed to functionfs, it
|
||
* internally uses a larger, aligned buffer so that such UDCs are happy.
|
||
*
|
||
* Unfortunately, this means that host may send more data than was
|
||
* requested in read(2) system call. f_fs doesn’t know what to do with
|
||
* that excess data so it simply drops it.
|
||
*
|
||
* Was the buffer aligned in the first place, no such problem would
|
||
* happen.
|
||
*
|
||
* Data may be dropped only in AIO reads. Synchronous reads are handled
|
||
* by splitting a request into multiple parts. This splitting may still
|
||
* be a problem though so it’s likely best to align the buffer
|
||
* regardless of it being AIO or not..
|
||
*
|
||
* This only affects OUT endpoints, i.e. reading data with a read(2),
|
||
* aio_read(2) etc. system calls. Writing data to an IN endpoint is not
|
||
* affected.
|
||
*/
|
||
pr_err("functionfs read size %d > requested size %zd, dropping excess data. "
|
||
"Align read buffer size to max packet size to avoid the problem.\n",
|
||
data_len, ret);
|
||
|
||
return ret;
|
||
}
|
||
|
||
/*
|
||
* allocate a virtually contiguous buffer and create a scatterlist describing it
|
||
* @sg_table - pointer to a place to be filled with sg_table contents
|
||
* @size - required buffer size
|
||
*/
|
||
static void *ffs_build_sg_list(struct sg_table *sgt, size_t sz)
|
||
{
|
||
struct page **pages;
|
||
void *vaddr, *ptr;
|
||
unsigned int n_pages;
|
||
int i;
|
||
|
||
vaddr = vmalloc(sz);
|
||
if (!vaddr)
|
||
return NULL;
|
||
|
||
n_pages = PAGE_ALIGN(sz) >> PAGE_SHIFT;
|
||
pages = kvmalloc_array(n_pages, sizeof(struct page *), GFP_KERNEL);
|
||
if (!pages) {
|
||
vfree(vaddr);
|
||
|
||
return NULL;
|
||
}
|
||
for (i = 0, ptr = vaddr; i < n_pages; ++i, ptr += PAGE_SIZE)
|
||
pages[i] = vmalloc_to_page(ptr);
|
||
|
||
if (sg_alloc_table_from_pages(sgt, pages, n_pages, 0, sz, GFP_KERNEL)) {
|
||
kvfree(pages);
|
||
vfree(vaddr);
|
||
|
||
return NULL;
|
||
}
|
||
kvfree(pages);
|
||
|
||
return vaddr;
|
||
}
|
||
|
||
static inline void *ffs_alloc_buffer(struct ffs_io_data *io_data,
|
||
size_t data_len)
|
||
{
|
||
if (io_data->use_sg)
|
||
return ffs_build_sg_list(&io_data->sgt, data_len);
|
||
|
||
return kmalloc(data_len, GFP_KERNEL);
|
||
}
|
||
|
||
static inline void ffs_free_buffer(struct ffs_io_data *io_data)
|
||
{
|
||
if (!io_data->buf)
|
||
return;
|
||
|
||
if (io_data->use_sg) {
|
||
sg_free_table(&io_data->sgt);
|
||
vfree(io_data->buf);
|
||
} else {
|
||
kfree(io_data->buf);
|
||
}
|
||
}
|
||
|
||
static void ffs_user_copy_worker(struct work_struct *work)
|
||
{
|
||
struct ffs_io_data *io_data = container_of(work, struct ffs_io_data,
|
||
work);
|
||
int ret = io_data->req->status ? io_data->req->status :
|
||
io_data->req->actual;
|
||
bool kiocb_has_eventfd = io_data->kiocb->ki_flags & IOCB_EVENTFD;
|
||
|
||
if (io_data->read && ret > 0) {
|
||
mm_segment_t oldfs = get_fs();
|
||
|
||
set_fs(USER_DS);
|
||
use_mm(io_data->mm);
|
||
ret = ffs_copy_to_iter(io_data->buf, ret, &io_data->data);
|
||
unuse_mm(io_data->mm);
|
||
set_fs(oldfs);
|
||
}
|
||
|
||
io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
|
||
|
||
if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
|
||
eventfd_signal(io_data->ffs->ffs_eventfd, 1);
|
||
|
||
usb_ep_free_request(io_data->ep, io_data->req);
|
||
|
||
if (io_data->read)
|
||
kfree(io_data->to_free);
|
||
ffs_free_buffer(io_data);
|
||
kfree(io_data);
|
||
}
|
||
|
||
static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
|
||
struct usb_request *req)
|
||
{
|
||
struct ffs_io_data *io_data = req->context;
|
||
struct ffs_data *ffs = io_data->ffs;
|
||
|
||
ENTER();
|
||
|
||
INIT_WORK(&io_data->work, ffs_user_copy_worker);
|
||
queue_work(ffs->io_completion_wq, &io_data->work);
|
||
}
|
||
|
||
static void __ffs_epfile_read_buffer_free(struct ffs_epfile *epfile)
|
||
{
|
||
/*
|
||
* See comment in struct ffs_epfile for full read_buffer pointer
|
||
* synchronisation story.
|
||
*/
|
||
struct ffs_buffer *buf = xchg(&epfile->read_buffer, READ_BUFFER_DROP);
|
||
if (buf && buf != READ_BUFFER_DROP)
|
||
kfree(buf);
|
||
}
|
||
|
||
/* Assumes epfile->mutex is held. */
|
||
static ssize_t __ffs_epfile_read_buffered(struct ffs_epfile *epfile,
|
||
struct iov_iter *iter)
|
||
{
|
||
/*
|
||
* Null out epfile->read_buffer so ffs_func_eps_disable does not free
|
||
* the buffer while we are using it. See comment in struct ffs_epfile
|
||
* for full read_buffer pointer synchronisation story.
|
||
*/
|
||
struct ffs_buffer *buf = xchg(&epfile->read_buffer, NULL);
|
||
ssize_t ret;
|
||
if (!buf || buf == READ_BUFFER_DROP)
|
||
return 0;
|
||
|
||
ret = copy_to_iter(buf->data, buf->length, iter);
|
||
if (buf->length == ret) {
|
||
kfree(buf);
|
||
return ret;
|
||
}
|
||
|
||
if (unlikely(iov_iter_count(iter))) {
|
||
ret = -EFAULT;
|
||
} else {
|
||
buf->length -= ret;
|
||
buf->data += ret;
|
||
}
|
||
|
||
if (cmpxchg(&epfile->read_buffer, NULL, buf))
|
||
kfree(buf);
|
||
|
||
return ret;
|
||
}
|
||
|
||
/* Assumes epfile->mutex is held. */
|
||
static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
|
||
void *data, int data_len,
|
||
struct iov_iter *iter)
|
||
{
|
||
struct ffs_buffer *buf;
|
||
|
||
ssize_t ret = copy_to_iter(data, data_len, iter);
|
||
if (likely(data_len == ret))
|
||
return ret;
|
||
|
||
if (unlikely(iov_iter_count(iter)))
|
||
return -EFAULT;
|
||
|
||
/* See ffs_copy_to_iter for more context. */
|
||
pr_warn("functionfs read size %d > requested size %zd, splitting request into multiple reads.",
|
||
data_len, ret);
|
||
|
||
data_len -= ret;
|
||
buf = kmalloc(sizeof(*buf) + data_len, GFP_KERNEL);
|
||
if (!buf)
|
||
return -ENOMEM;
|
||
buf->length = data_len;
|
||
buf->data = buf->storage;
|
||
memcpy(buf->storage, data + ret, data_len);
|
||
|
||
/*
|
||
* At this point read_buffer is NULL or READ_BUFFER_DROP (if
|
||
* ffs_func_eps_disable has been called in the meanwhile). See comment
|
||
* in struct ffs_epfile for full read_buffer pointer synchronisation
|
||
* story.
|
||
*/
|
||
if (unlikely(cmpxchg(&epfile->read_buffer, NULL, buf)))
|
||
kfree(buf);
|
||
|
||
return ret;
|
||
}
|
||
|
||
static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
|
||
{
|
||
struct ffs_epfile *epfile = file->private_data;
|
||
struct usb_request *req;
|
||
struct ffs_ep *ep;
|
||
char *data = NULL;
|
||
ssize_t ret, data_len = -EINVAL;
|
||
int halt;
|
||
|
||
/* Are we still active? */
|
||
if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
|
||
return -ENODEV;
|
||
|
||
/* Wait for endpoint to be enabled */
|
||
ep = epfile->ep;
|
||
if (!ep) {
|
||
if (file->f_flags & O_NONBLOCK)
|
||
return -EAGAIN;
|
||
|
||
ret = wait_event_interruptible(
|
||
epfile->ffs->wait, (ep = epfile->ep));
|
||
if (ret)
|
||
return -EINTR;
|
||
}
|
||
|
||
/* Do we halt? */
|
||
halt = (!io_data->read == !epfile->in);
|
||
if (halt && epfile->isoc)
|
||
return -EINVAL;
|
||
|
||
/* We will be using request and read_buffer */
|
||
ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
|
||
if (unlikely(ret))
|
||
goto error;
|
||
|
||
/* Allocate & copy */
|
||
if (!halt) {
|
||
struct usb_gadget *gadget;
|
||
|
||
/*
|
||
* Do we have buffered data from previous partial read? Check
|
||
* that for synchronous case only because we do not have
|
||
* facility to ‘wake up’ a pending asynchronous read and push
|
||
* buffered data to it which we would need to make things behave
|
||
* consistently.
|
||
*/
|
||
if (!io_data->aio && io_data->read) {
|
||
ret = __ffs_epfile_read_buffered(epfile, &io_data->data);
|
||
if (ret)
|
||
goto error_mutex;
|
||
}
|
||
|
||
/*
|
||
* if we _do_ wait above, the epfile->ffs->gadget might be NULL
|
||
* before the waiting completes, so do not assign to 'gadget'
|
||
* earlier
|
||
*/
|
||
gadget = epfile->ffs->gadget;
|
||
|
||
spin_lock_irq(&epfile->ffs->eps_lock);
|
||
/* In the meantime, endpoint got disabled or changed. */
|
||
if (epfile->ep != ep) {
|
||
ret = -ESHUTDOWN;
|
||
goto error_lock;
|
||
}
|
||
data_len = iov_iter_count(&io_data->data);
|
||
/*
|
||
* Controller may require buffer size to be aligned to
|
||
* maxpacketsize of an out endpoint.
|
||
*/
|
||
if (io_data->read)
|
||
data_len = usb_ep_align_maybe(gadget, ep->ep, data_len);
|
||
|
||
io_data->use_sg = gadget->sg_supported && data_len > PAGE_SIZE;
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
|
||
data = ffs_alloc_buffer(io_data, data_len);
|
||
if (unlikely(!data)) {
|
||
ret = -ENOMEM;
|
||
goto error_mutex;
|
||
}
|
||
if (!io_data->read &&
|
||
!copy_from_iter_full(data, data_len, &io_data->data)) {
|
||
ret = -EFAULT;
|
||
goto error_mutex;
|
||
}
|
||
}
|
||
|
||
spin_lock_irq(&epfile->ffs->eps_lock);
|
||
|
||
if (epfile->ep != ep) {
|
||
/* In the meantime, endpoint got disabled or changed. */
|
||
ret = -ESHUTDOWN;
|
||
} else if (halt) {
|
||
ret = usb_ep_set_halt(ep->ep);
|
||
if (!ret)
|
||
ret = -EBADMSG;
|
||
} else if (unlikely(data_len == -EINVAL)) {
|
||
/*
|
||
* Sanity Check: even though data_len can't be used
|
||
* uninitialized at the time I write this comment, some
|
||
* compilers complain about this situation.
|
||
* In order to keep the code clean from warnings, data_len is
|
||
* being initialized to -EINVAL during its declaration, which
|
||
* means we can't rely on compiler anymore to warn no future
|
||
* changes won't result in data_len being used uninitialized.
|
||
* For such reason, we're adding this redundant sanity check
|
||
* here.
|
||
*/
|
||
WARN(1, "%s: data_len == -EINVAL\n", __func__);
|
||
ret = -EINVAL;
|
||
} else if (!io_data->aio) {
|
||
DECLARE_COMPLETION_ONSTACK(done);
|
||
bool interrupted = false;
|
||
|
||
req = ep->req;
|
||
if (io_data->use_sg) {
|
||
req->buf = NULL;
|
||
req->sg = io_data->sgt.sgl;
|
||
req->num_sgs = io_data->sgt.nents;
|
||
} else {
|
||
req->buf = data;
|
||
req->num_sgs = 0;
|
||
}
|
||
req->length = data_len;
|
||
|
||
io_data->buf = data;
|
||
|
||
req->context = &done;
|
||
req->complete = ffs_epfile_io_complete;
|
||
|
||
ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
|
||
if (unlikely(ret < 0))
|
||
goto error_lock;
|
||
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
|
||
if (unlikely(wait_for_completion_interruptible(&done))) {
|
||
/*
|
||
* To avoid race condition with ffs_epfile_io_complete,
|
||
* dequeue the request first then check
|
||
* status. usb_ep_dequeue API should guarantee no race
|
||
* condition with req->complete callback.
|
||
*/
|
||
usb_ep_dequeue(ep->ep, req);
|
||
wait_for_completion(&done);
|
||
interrupted = ep->status < 0;
|
||
}
|
||
|
||
if (interrupted)
|
||
ret = -EINTR;
|
||
else if (io_data->read && ep->status > 0)
|
||
ret = __ffs_epfile_read_data(epfile, data, ep->status,
|
||
&io_data->data);
|
||
else
|
||
ret = ep->status;
|
||
goto error_mutex;
|
||
} else if (!(req = usb_ep_alloc_request(ep->ep, GFP_ATOMIC))) {
|
||
ret = -ENOMEM;
|
||
} else {
|
||
if (io_data->use_sg) {
|
||
req->buf = NULL;
|
||
req->sg = io_data->sgt.sgl;
|
||
req->num_sgs = io_data->sgt.nents;
|
||
} else {
|
||
req->buf = data;
|
||
req->num_sgs = 0;
|
||
}
|
||
req->length = data_len;
|
||
|
||
io_data->buf = data;
|
||
io_data->ep = ep->ep;
|
||
io_data->req = req;
|
||
io_data->ffs = epfile->ffs;
|
||
|
||
req->context = io_data;
|
||
req->complete = ffs_epfile_async_io_complete;
|
||
|
||
ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
|
||
if (unlikely(ret)) {
|
||
io_data->req = NULL;
|
||
usb_ep_free_request(ep->ep, req);
|
||
goto error_lock;
|
||
}
|
||
|
||
ret = -EIOCBQUEUED;
|
||
/*
|
||
* Do not kfree the buffer in this function. It will be freed
|
||
* by ffs_user_copy_worker.
|
||
*/
|
||
data = NULL;
|
||
}
|
||
|
||
error_lock:
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
error_mutex:
|
||
mutex_unlock(&epfile->mutex);
|
||
error:
|
||
if (ret != -EIOCBQUEUED) /* don't free if there is iocb queued */
|
||
ffs_free_buffer(io_data);
|
||
return ret;
|
||
}
|
||
|
||
static int
|
||
ffs_epfile_open(struct inode *inode, struct file *file)
|
||
{
|
||
struct ffs_epfile *epfile = inode->i_private;
|
||
|
||
ENTER();
|
||
|
||
if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
|
||
return -ENODEV;
|
||
|
||
file->private_data = epfile;
|
||
ffs_data_opened(epfile->ffs);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int ffs_aio_cancel(struct kiocb *kiocb)
|
||
{
|
||
struct ffs_io_data *io_data = kiocb->private;
|
||
struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
|
||
unsigned long flags;
|
||
int value;
|
||
|
||
ENTER();
|
||
|
||
spin_lock_irqsave(&epfile->ffs->eps_lock, flags);
|
||
|
||
if (likely(io_data && io_data->ep && io_data->req))
|
||
value = usb_ep_dequeue(io_data->ep, io_data->req);
|
||
else
|
||
value = -EINVAL;
|
||
|
||
spin_unlock_irqrestore(&epfile->ffs->eps_lock, flags);
|
||
|
||
return value;
|
||
}
|
||
|
||
static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
|
||
{
|
||
struct ffs_io_data io_data, *p = &io_data;
|
||
ssize_t res;
|
||
|
||
ENTER();
|
||
|
||
if (!is_sync_kiocb(kiocb)) {
|
||
p = kzalloc(sizeof(io_data), GFP_KERNEL);
|
||
if (unlikely(!p))
|
||
return -ENOMEM;
|
||
p->aio = true;
|
||
} else {
|
||
memset(p, 0, sizeof(*p));
|
||
p->aio = false;
|
||
}
|
||
|
||
p->read = false;
|
||
p->kiocb = kiocb;
|
||
p->data = *from;
|
||
p->mm = current->mm;
|
||
|
||
kiocb->private = p;
|
||
|
||
if (p->aio)
|
||
kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
|
||
|
||
res = ffs_epfile_io(kiocb->ki_filp, p);
|
||
if (res == -EIOCBQUEUED)
|
||
return res;
|
||
if (p->aio)
|
||
kfree(p);
|
||
else
|
||
*from = p->data;
|
||
return res;
|
||
}
|
||
|
||
static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
|
||
{
|
||
struct ffs_io_data io_data, *p = &io_data;
|
||
ssize_t res;
|
||
|
||
ENTER();
|
||
|
||
if (!is_sync_kiocb(kiocb)) {
|
||
p = kzalloc(sizeof(io_data), GFP_KERNEL);
|
||
if (unlikely(!p))
|
||
return -ENOMEM;
|
||
p->aio = true;
|
||
} else {
|
||
memset(p, 0, sizeof(*p));
|
||
p->aio = false;
|
||
}
|
||
|
||
p->read = true;
|
||
p->kiocb = kiocb;
|
||
if (p->aio) {
|
||
p->to_free = dup_iter(&p->data, to, GFP_KERNEL);
|
||
if (!p->to_free) {
|
||
kfree(p);
|
||
return -ENOMEM;
|
||
}
|
||
} else {
|
||
p->data = *to;
|
||
p->to_free = NULL;
|
||
}
|
||
p->mm = current->mm;
|
||
|
||
kiocb->private = p;
|
||
|
||
if (p->aio)
|
||
kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
|
||
|
||
res = ffs_epfile_io(kiocb->ki_filp, p);
|
||
if (res == -EIOCBQUEUED)
|
||
return res;
|
||
|
||
if (p->aio) {
|
||
kfree(p->to_free);
|
||
kfree(p);
|
||
} else {
|
||
*to = p->data;
|
||
}
|
||
return res;
|
||
}
|
||
|
||
static int
|
||
ffs_epfile_release(struct inode *inode, struct file *file)
|
||
{
|
||
struct ffs_epfile *epfile = inode->i_private;
|
||
|
||
ENTER();
|
||
|
||
__ffs_epfile_read_buffer_free(epfile);
|
||
ffs_data_closed(epfile->ffs);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static long ffs_epfile_ioctl(struct file *file, unsigned code,
|
||
unsigned long value)
|
||
{
|
||
struct ffs_epfile *epfile = file->private_data;
|
||
struct ffs_ep *ep;
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
|
||
return -ENODEV;
|
||
|
||
/* Wait for endpoint to be enabled */
|
||
ep = epfile->ep;
|
||
if (!ep) {
|
||
if (file->f_flags & O_NONBLOCK)
|
||
return -EAGAIN;
|
||
|
||
ret = wait_event_interruptible(
|
||
epfile->ffs->wait, (ep = epfile->ep));
|
||
if (ret)
|
||
return -EINTR;
|
||
}
|
||
|
||
spin_lock_irq(&epfile->ffs->eps_lock);
|
||
|
||
/* In the meantime, endpoint got disabled or changed. */
|
||
if (epfile->ep != ep) {
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
return -ESHUTDOWN;
|
||
}
|
||
|
||
switch (code) {
|
||
case FUNCTIONFS_FIFO_STATUS:
|
||
ret = usb_ep_fifo_status(epfile->ep->ep);
|
||
break;
|
||
case FUNCTIONFS_FIFO_FLUSH:
|
||
usb_ep_fifo_flush(epfile->ep->ep);
|
||
ret = 0;
|
||
break;
|
||
case FUNCTIONFS_CLEAR_HALT:
|
||
ret = usb_ep_clear_halt(epfile->ep->ep);
|
||
break;
|
||
case FUNCTIONFS_ENDPOINT_REVMAP:
|
||
ret = epfile->ep->num;
|
||
break;
|
||
case FUNCTIONFS_ENDPOINT_DESC:
|
||
{
|
||
int desc_idx;
|
||
struct usb_endpoint_descriptor *desc;
|
||
|
||
switch (epfile->ffs->gadget->speed) {
|
||
case USB_SPEED_SUPER:
|
||
desc_idx = 2;
|
||
break;
|
||
case USB_SPEED_HIGH:
|
||
desc_idx = 1;
|
||
break;
|
||
default:
|
||
desc_idx = 0;
|
||
}
|
||
desc = epfile->ep->descs[desc_idx];
|
||
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
ret = copy_to_user((void __user *)value, desc, desc->bLength);
|
||
if (ret)
|
||
ret = -EFAULT;
|
||
return ret;
|
||
}
|
||
default:
|
||
ret = -ENOTTY;
|
||
}
|
||
spin_unlock_irq(&epfile->ffs->eps_lock);
|
||
|
||
return ret;
|
||
}
|
||
|
||
static const struct file_operations ffs_epfile_operations = {
|
||
.llseek = no_llseek,
|
||
|
||
.open = ffs_epfile_open,
|
||
.write_iter = ffs_epfile_write_iter,
|
||
.read_iter = ffs_epfile_read_iter,
|
||
.release = ffs_epfile_release,
|
||
.unlocked_ioctl = ffs_epfile_ioctl,
|
||
.compat_ioctl = compat_ptr_ioctl,
|
||
};
|
||
|
||
|
||
/* File system and super block operations ***********************************/
|
||
|
||
/*
|
||
* Mounting the file system creates a controller file, used first for
|
||
* function configuration then later for event monitoring.
|
||
*/
|
||
|
||
static struct inode *__must_check
|
||
ffs_sb_make_inode(struct super_block *sb, void *data,
|
||
const struct file_operations *fops,
|
||
const struct inode_operations *iops,
|
||
struct ffs_file_perms *perms)
|
||
{
|
||
struct inode *inode;
|
||
|
||
ENTER();
|
||
|
||
inode = new_inode(sb);
|
||
|
||
if (likely(inode)) {
|
||
struct timespec64 ts = current_time(inode);
|
||
|
||
inode->i_ino = get_next_ino();
|
||
inode->i_mode = perms->mode;
|
||
inode->i_uid = perms->uid;
|
||
inode->i_gid = perms->gid;
|
||
inode->i_atime = ts;
|
||
inode->i_mtime = ts;
|
||
inode->i_ctime = ts;
|
||
inode->i_private = data;
|
||
if (fops)
|
||
inode->i_fop = fops;
|
||
if (iops)
|
||
inode->i_op = iops;
|
||
}
|
||
|
||
return inode;
|
||
}
|
||
|
||
/* Create "regular" file */
|
||
static struct dentry *ffs_sb_create_file(struct super_block *sb,
|
||
const char *name, void *data,
|
||
const struct file_operations *fops)
|
||
{
|
||
struct ffs_data *ffs = sb->s_fs_info;
|
||
struct dentry *dentry;
|
||
struct inode *inode;
|
||
|
||
ENTER();
|
||
|
||
dentry = d_alloc_name(sb->s_root, name);
|
||
if (unlikely(!dentry))
|
||
return NULL;
|
||
|
||
inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
|
||
if (unlikely(!inode)) {
|
||
dput(dentry);
|
||
return NULL;
|
||
}
|
||
|
||
d_add(dentry, inode);
|
||
return dentry;
|
||
}
|
||
|
||
/* Super block */
|
||
static const struct super_operations ffs_sb_operations = {
|
||
.statfs = simple_statfs,
|
||
.drop_inode = generic_delete_inode,
|
||
};
|
||
|
||
struct ffs_sb_fill_data {
|
||
struct ffs_file_perms perms;
|
||
umode_t root_mode;
|
||
const char *dev_name;
|
||
bool no_disconnect;
|
||
struct ffs_data *ffs_data;
|
||
};
|
||
|
||
static int ffs_sb_fill(struct super_block *sb, struct fs_context *fc)
|
||
{
|
||
struct ffs_sb_fill_data *data = fc->fs_private;
|
||
struct inode *inode;
|
||
struct ffs_data *ffs = data->ffs_data;
|
||
|
||
ENTER();
|
||
|
||
ffs->sb = sb;
|
||
data->ffs_data = NULL;
|
||
sb->s_fs_info = ffs;
|
||
sb->s_blocksize = PAGE_SIZE;
|
||
sb->s_blocksize_bits = PAGE_SHIFT;
|
||
sb->s_magic = FUNCTIONFS_MAGIC;
|
||
sb->s_op = &ffs_sb_operations;
|
||
sb->s_time_gran = 1;
|
||
|
||
/* Root inode */
|
||
data->perms.mode = data->root_mode;
|
||
inode = ffs_sb_make_inode(sb, NULL,
|
||
&simple_dir_operations,
|
||
&simple_dir_inode_operations,
|
||
&data->perms);
|
||
sb->s_root = d_make_root(inode);
|
||
if (unlikely(!sb->s_root))
|
||
return -ENOMEM;
|
||
|
||
/* EP0 file */
|
||
if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
|
||
&ffs_ep0_operations)))
|
||
return -ENOMEM;
|
||
|
||
return 0;
|
||
}
|
||
|
||
enum {
|
||
Opt_no_disconnect,
|
||
Opt_rmode,
|
||
Opt_fmode,
|
||
Opt_mode,
|
||
Opt_uid,
|
||
Opt_gid,
|
||
};
|
||
|
||
static const struct fs_parameter_spec ffs_fs_fs_parameters[] = {
|
||
fsparam_bool ("no_disconnect", Opt_no_disconnect),
|
||
fsparam_u32 ("rmode", Opt_rmode),
|
||
fsparam_u32 ("fmode", Opt_fmode),
|
||
fsparam_u32 ("mode", Opt_mode),
|
||
fsparam_u32 ("uid", Opt_uid),
|
||
fsparam_u32 ("gid", Opt_gid),
|
||
{}
|
||
};
|
||
|
||
static int ffs_fs_parse_param(struct fs_context *fc, struct fs_parameter *param)
|
||
{
|
||
struct ffs_sb_fill_data *data = fc->fs_private;
|
||
struct fs_parse_result result;
|
||
int opt;
|
||
|
||
ENTER();
|
||
|
||
opt = fs_parse(fc, ffs_fs_fs_parameters, param, &result);
|
||
if (opt < 0)
|
||
return opt;
|
||
|
||
switch (opt) {
|
||
case Opt_no_disconnect:
|
||
data->no_disconnect = result.boolean;
|
||
break;
|
||
case Opt_rmode:
|
||
data->root_mode = (result.uint_32 & 0555) | S_IFDIR;
|
||
break;
|
||
case Opt_fmode:
|
||
data->perms.mode = (result.uint_32 & 0666) | S_IFREG;
|
||
break;
|
||
case Opt_mode:
|
||
data->root_mode = (result.uint_32 & 0555) | S_IFDIR;
|
||
data->perms.mode = (result.uint_32 & 0666) | S_IFREG;
|
||
break;
|
||
|
||
case Opt_uid:
|
||
data->perms.uid = make_kuid(current_user_ns(), result.uint_32);
|
||
if (!uid_valid(data->perms.uid))
|
||
goto unmapped_value;
|
||
break;
|
||
case Opt_gid:
|
||
data->perms.gid = make_kgid(current_user_ns(), result.uint_32);
|
||
if (!gid_valid(data->perms.gid))
|
||
goto unmapped_value;
|
||
break;
|
||
|
||
default:
|
||
return -ENOPARAM;
|
||
}
|
||
|
||
return 0;
|
||
|
||
unmapped_value:
|
||
return invalf(fc, "%s: unmapped value: %u", param->key, result.uint_32);
|
||
}
|
||
|
||
/*
|
||
* Set up the superblock for a mount.
|
||
*/
|
||
static int ffs_fs_get_tree(struct fs_context *fc)
|
||
{
|
||
struct ffs_sb_fill_data *ctx = fc->fs_private;
|
||
void *ffs_dev;
|
||
struct ffs_data *ffs;
|
||
|
||
ENTER();
|
||
|
||
if (!fc->source)
|
||
return invalf(fc, "No source specified");
|
||
|
||
ffs = ffs_data_new(fc->source);
|
||
if (unlikely(!ffs))
|
||
return -ENOMEM;
|
||
ffs->file_perms = ctx->perms;
|
||
ffs->no_disconnect = ctx->no_disconnect;
|
||
|
||
ffs->dev_name = kstrdup(fc->source, GFP_KERNEL);
|
||
if (unlikely(!ffs->dev_name)) {
|
||
ffs_data_put(ffs);
|
||
return -ENOMEM;
|
||
}
|
||
|
||
ffs_dev = ffs_acquire_dev(ffs->dev_name);
|
||
if (IS_ERR(ffs_dev)) {
|
||
ffs_data_put(ffs);
|
||
return PTR_ERR(ffs_dev);
|
||
}
|
||
|
||
ffs->private_data = ffs_dev;
|
||
ctx->ffs_data = ffs;
|
||
return get_tree_nodev(fc, ffs_sb_fill);
|
||
}
|
||
|
||
static void ffs_fs_free_fc(struct fs_context *fc)
|
||
{
|
||
struct ffs_sb_fill_data *ctx = fc->fs_private;
|
||
|
||
if (ctx) {
|
||
if (ctx->ffs_data) {
|
||
ffs_release_dev(ctx->ffs_data);
|
||
ffs_data_put(ctx->ffs_data);
|
||
}
|
||
|
||
kfree(ctx);
|
||
}
|
||
}
|
||
|
||
static const struct fs_context_operations ffs_fs_context_ops = {
|
||
.free = ffs_fs_free_fc,
|
||
.parse_param = ffs_fs_parse_param,
|
||
.get_tree = ffs_fs_get_tree,
|
||
};
|
||
|
||
static int ffs_fs_init_fs_context(struct fs_context *fc)
|
||
{
|
||
struct ffs_sb_fill_data *ctx;
|
||
|
||
ctx = kzalloc(sizeof(struct ffs_sb_fill_data), GFP_KERNEL);
|
||
if (!ctx)
|
||
return -ENOMEM;
|
||
|
||
ctx->perms.mode = S_IFREG | 0600;
|
||
ctx->perms.uid = GLOBAL_ROOT_UID;
|
||
ctx->perms.gid = GLOBAL_ROOT_GID;
|
||
ctx->root_mode = S_IFDIR | 0500;
|
||
ctx->no_disconnect = false;
|
||
|
||
fc->fs_private = ctx;
|
||
fc->ops = &ffs_fs_context_ops;
|
||
return 0;
|
||
}
|
||
|
||
static void
|
||
ffs_fs_kill_sb(struct super_block *sb)
|
||
{
|
||
ENTER();
|
||
|
||
kill_litter_super(sb);
|
||
if (sb->s_fs_info) {
|
||
ffs_release_dev(sb->s_fs_info);
|
||
ffs_data_closed(sb->s_fs_info);
|
||
}
|
||
}
|
||
|
||
static struct file_system_type ffs_fs_type = {
|
||
.owner = THIS_MODULE,
|
||
.name = "functionfs",
|
||
.init_fs_context = ffs_fs_init_fs_context,
|
||
.parameters = ffs_fs_fs_parameters,
|
||
.kill_sb = ffs_fs_kill_sb,
|
||
};
|
||
MODULE_ALIAS_FS("functionfs");
|
||
|
||
|
||
/* Driver's main init/cleanup functions *************************************/
|
||
|
||
static int functionfs_init(void)
|
||
{
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
ret = register_filesystem(&ffs_fs_type);
|
||
if (likely(!ret))
|
||
pr_info("file system registered\n");
|
||
else
|
||
pr_err("failed registering file system (%d)\n", ret);
|
||
|
||
return ret;
|
||
}
|
||
|
||
static void functionfs_cleanup(void)
|
||
{
|
||
ENTER();
|
||
|
||
pr_info("unloading\n");
|
||
unregister_filesystem(&ffs_fs_type);
|
||
}
|
||
|
||
|
||
/* ffs_data and ffs_function construction and destruction code **************/
|
||
|
||
static void ffs_data_clear(struct ffs_data *ffs);
|
||
static void ffs_data_reset(struct ffs_data *ffs);
|
||
|
||
static void ffs_data_get(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
refcount_inc(&ffs->ref);
|
||
}
|
||
|
||
static void ffs_data_opened(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
refcount_inc(&ffs->ref);
|
||
if (atomic_add_return(1, &ffs->opened) == 1 &&
|
||
ffs->state == FFS_DEACTIVATED) {
|
||
ffs->state = FFS_CLOSING;
|
||
ffs_data_reset(ffs);
|
||
}
|
||
}
|
||
|
||
static void ffs_data_put(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
if (unlikely(refcount_dec_and_test(&ffs->ref))) {
|
||
pr_info("%s(): freeing\n", __func__);
|
||
ffs_data_clear(ffs);
|
||
BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
|
||
swait_active(&ffs->ep0req_completion.wait) ||
|
||
waitqueue_active(&ffs->wait));
|
||
destroy_workqueue(ffs->io_completion_wq);
|
||
kfree(ffs->dev_name);
|
||
kfree(ffs);
|
||
}
|
||
}
|
||
|
||
static void ffs_data_closed(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
if (atomic_dec_and_test(&ffs->opened)) {
|
||
if (ffs->no_disconnect) {
|
||
ffs->state = FFS_DEACTIVATED;
|
||
if (ffs->epfiles) {
|
||
ffs_epfiles_destroy(ffs->epfiles,
|
||
ffs->eps_count);
|
||
ffs->epfiles = NULL;
|
||
}
|
||
if (ffs->setup_state == FFS_SETUP_PENDING)
|
||
__ffs_ep0_stall(ffs);
|
||
} else {
|
||
ffs->state = FFS_CLOSING;
|
||
ffs_data_reset(ffs);
|
||
}
|
||
}
|
||
if (atomic_read(&ffs->opened) < 0) {
|
||
ffs->state = FFS_CLOSING;
|
||
ffs_data_reset(ffs);
|
||
}
|
||
|
||
ffs_data_put(ffs);
|
||
}
|
||
|
||
static struct ffs_data *ffs_data_new(const char *dev_name)
|
||
{
|
||
struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
|
||
if (unlikely(!ffs))
|
||
return NULL;
|
||
|
||
ENTER();
|
||
|
||
ffs->io_completion_wq = alloc_ordered_workqueue("%s", 0, dev_name);
|
||
if (!ffs->io_completion_wq) {
|
||
kfree(ffs);
|
||
return NULL;
|
||
}
|
||
|
||
refcount_set(&ffs->ref, 1);
|
||
atomic_set(&ffs->opened, 0);
|
||
ffs->state = FFS_READ_DESCRIPTORS;
|
||
mutex_init(&ffs->mutex);
|
||
spin_lock_init(&ffs->eps_lock);
|
||
init_waitqueue_head(&ffs->ev.waitq);
|
||
init_waitqueue_head(&ffs->wait);
|
||
init_completion(&ffs->ep0req_completion);
|
||
|
||
/* XXX REVISIT need to update it in some places, or do we? */
|
||
ffs->ev.can_stall = 1;
|
||
|
||
return ffs;
|
||
}
|
||
|
||
static void ffs_data_clear(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
ffs_closed(ffs);
|
||
|
||
BUG_ON(ffs->gadget);
|
||
|
||
if (ffs->epfiles)
|
||
ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
|
||
|
||
if (ffs->ffs_eventfd)
|
||
eventfd_ctx_put(ffs->ffs_eventfd);
|
||
|
||
kfree(ffs->raw_descs_data);
|
||
kfree(ffs->raw_strings);
|
||
kfree(ffs->stringtabs);
|
||
}
|
||
|
||
static void ffs_data_reset(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
ffs_data_clear(ffs);
|
||
|
||
ffs->epfiles = NULL;
|
||
ffs->raw_descs_data = NULL;
|
||
ffs->raw_descs = NULL;
|
||
ffs->raw_strings = NULL;
|
||
ffs->stringtabs = NULL;
|
||
|
||
ffs->raw_descs_length = 0;
|
||
ffs->fs_descs_count = 0;
|
||
ffs->hs_descs_count = 0;
|
||
ffs->ss_descs_count = 0;
|
||
|
||
ffs->strings_count = 0;
|
||
ffs->interfaces_count = 0;
|
||
ffs->eps_count = 0;
|
||
|
||
ffs->ev.count = 0;
|
||
|
||
ffs->state = FFS_READ_DESCRIPTORS;
|
||
ffs->setup_state = FFS_NO_SETUP;
|
||
ffs->flags = 0;
|
||
|
||
ffs->ms_os_descs_ext_prop_count = 0;
|
||
ffs->ms_os_descs_ext_prop_name_len = 0;
|
||
ffs->ms_os_descs_ext_prop_data_len = 0;
|
||
}
|
||
|
||
|
||
static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
|
||
{
|
||
struct usb_gadget_strings **lang;
|
||
int first_id;
|
||
|
||
ENTER();
|
||
|
||
if (WARN_ON(ffs->state != FFS_ACTIVE
|
||
|| test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
|
||
return -EBADFD;
|
||
|
||
first_id = usb_string_ids_n(cdev, ffs->strings_count);
|
||
if (unlikely(first_id < 0))
|
||
return first_id;
|
||
|
||
ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
|
||
if (unlikely(!ffs->ep0req))
|
||
return -ENOMEM;
|
||
ffs->ep0req->complete = ffs_ep0_complete;
|
||
ffs->ep0req->context = ffs;
|
||
|
||
lang = ffs->stringtabs;
|
||
if (lang) {
|
||
for (; *lang; ++lang) {
|
||
struct usb_string *str = (*lang)->strings;
|
||
int id = first_id;
|
||
for (; str->s; ++id, ++str)
|
||
str->id = id;
|
||
}
|
||
}
|
||
|
||
ffs->gadget = cdev->gadget;
|
||
ffs_data_get(ffs);
|
||
return 0;
|
||
}
|
||
|
||
static void functionfs_unbind(struct ffs_data *ffs)
|
||
{
|
||
ENTER();
|
||
|
||
if (!WARN_ON(!ffs->gadget)) {
|
||
usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
|
||
ffs->ep0req = NULL;
|
||
ffs->gadget = NULL;
|
||
clear_bit(FFS_FL_BOUND, &ffs->flags);
|
||
ffs_data_put(ffs);
|
||
}
|
||
}
|
||
|
||
static int ffs_epfiles_create(struct ffs_data *ffs)
|
||
{
|
||
struct ffs_epfile *epfile, *epfiles;
|
||
unsigned i, count;
|
||
|
||
ENTER();
|
||
|
||
count = ffs->eps_count;
|
||
epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
|
||
if (!epfiles)
|
||
return -ENOMEM;
|
||
|
||
epfile = epfiles;
|
||
for (i = 1; i <= count; ++i, ++epfile) {
|
||
epfile->ffs = ffs;
|
||
mutex_init(&epfile->mutex);
|
||
if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
|
||
sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
|
||
else
|
||
sprintf(epfile->name, "ep%u", i);
|
||
epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
|
||
epfile,
|
||
&ffs_epfile_operations);
|
||
if (unlikely(!epfile->dentry)) {
|
||
ffs_epfiles_destroy(epfiles, i - 1);
|
||
return -ENOMEM;
|
||
}
|
||
}
|
||
|
||
ffs->epfiles = epfiles;
|
||
return 0;
|
||
}
|
||
|
||
static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
|
||
{
|
||
struct ffs_epfile *epfile = epfiles;
|
||
|
||
ENTER();
|
||
|
||
for (; count; --count, ++epfile) {
|
||
BUG_ON(mutex_is_locked(&epfile->mutex));
|
||
if (epfile->dentry) {
|
||
d_delete(epfile->dentry);
|
||
dput(epfile->dentry);
|
||
epfile->dentry = NULL;
|
||
}
|
||
}
|
||
|
||
kfree(epfiles);
|
||
}
|
||
|
||
static void ffs_func_eps_disable(struct ffs_function *func)
|
||
{
|
||
struct ffs_ep *ep = func->eps;
|
||
struct ffs_epfile *epfile = func->ffs->epfiles;
|
||
unsigned count = func->ffs->eps_count;
|
||
unsigned long flags;
|
||
|
||
spin_lock_irqsave(&func->ffs->eps_lock, flags);
|
||
while (count--) {
|
||
/* pending requests get nuked */
|
||
if (likely(ep->ep))
|
||
usb_ep_disable(ep->ep);
|
||
++ep;
|
||
|
||
if (epfile) {
|
||
epfile->ep = NULL;
|
||
__ffs_epfile_read_buffer_free(epfile);
|
||
++epfile;
|
||
}
|
||
}
|
||
spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
|
||
}
|
||
|
||
static int ffs_func_eps_enable(struct ffs_function *func)
|
||
{
|
||
struct ffs_data *ffs = func->ffs;
|
||
struct ffs_ep *ep = func->eps;
|
||
struct ffs_epfile *epfile = ffs->epfiles;
|
||
unsigned count = ffs->eps_count;
|
||
unsigned long flags;
|
||
int ret = 0;
|
||
|
||
spin_lock_irqsave(&func->ffs->eps_lock, flags);
|
||
while(count--) {
|
||
ep->ep->driver_data = ep;
|
||
|
||
ret = config_ep_by_speed(func->gadget, &func->function, ep->ep);
|
||
if (ret) {
|
||
pr_err("%s: config_ep_by_speed(%s) returned %d\n",
|
||
__func__, ep->ep->name, ret);
|
||
break;
|
||
}
|
||
|
||
ret = usb_ep_enable(ep->ep);
|
||
if (likely(!ret)) {
|
||
epfile->ep = ep;
|
||
epfile->in = usb_endpoint_dir_in(ep->ep->desc);
|
||
epfile->isoc = usb_endpoint_xfer_isoc(ep->ep->desc);
|
||
} else {
|
||
break;
|
||
}
|
||
|
||
++ep;
|
||
++epfile;
|
||
}
|
||
|
||
wake_up_interruptible(&ffs->wait);
|
||
spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
|
||
|
||
return ret;
|
||
}
|
||
|
||
|
||
/* Parsing and building descriptors and strings *****************************/
|
||
|
||
/*
|
||
* This validates if data pointed by data is a valid USB descriptor as
|
||
* well as record how many interfaces, endpoints and strings are
|
||
* required by given configuration. Returns address after the
|
||
* descriptor or NULL if data is invalid.
|
||
*/
|
||
|
||
enum ffs_entity_type {
|
||
FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
|
||
};
|
||
|
||
enum ffs_os_desc_type {
|
||
FFS_OS_DESC, FFS_OS_DESC_EXT_COMPAT, FFS_OS_DESC_EXT_PROP
|
||
};
|
||
|
||
typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
|
||
u8 *valuep,
|
||
struct usb_descriptor_header *desc,
|
||
void *priv);
|
||
|
||
typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
|
||
struct usb_os_desc_header *h, void *data,
|
||
unsigned len, void *priv);
|
||
|
||
static int __must_check ffs_do_single_desc(char *data, unsigned len,
|
||
ffs_entity_callback entity,
|
||
void *priv, int *current_class)
|
||
{
|
||
struct usb_descriptor_header *_ds = (void *)data;
|
||
u8 length;
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
/* At least two bytes are required: length and type */
|
||
if (len < 2) {
|
||
pr_vdebug("descriptor too short\n");
|
||
return -EINVAL;
|
||
}
|
||
|
||
/* If we have at least as many bytes as the descriptor takes? */
|
||
length = _ds->bLength;
|
||
if (len < length) {
|
||
pr_vdebug("descriptor longer then available data\n");
|
||
return -EINVAL;
|
||
}
|
||
|
||
#define __entity_check_INTERFACE(val) 1
|
||
#define __entity_check_STRING(val) (val)
|
||
#define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
|
||
#define __entity(type, val) do { \
|
||
pr_vdebug("entity " #type "(%02x)\n", (val)); \
|
||
if (unlikely(!__entity_check_ ##type(val))) { \
|
||
pr_vdebug("invalid entity's value\n"); \
|
||
return -EINVAL; \
|
||
} \
|
||
ret = entity(FFS_ ##type, &val, _ds, priv); \
|
||
if (unlikely(ret < 0)) { \
|
||
pr_debug("entity " #type "(%02x); ret = %d\n", \
|
||
(val), ret); \
|
||
return ret; \
|
||
} \
|
||
} while (0)
|
||
|
||
/* Parse descriptor depending on type. */
|
||
switch (_ds->bDescriptorType) {
|
||
case USB_DT_DEVICE:
|
||
case USB_DT_CONFIG:
|
||
case USB_DT_STRING:
|
||
case USB_DT_DEVICE_QUALIFIER:
|
||
/* function can't have any of those */
|
||
pr_vdebug("descriptor reserved for gadget: %d\n",
|
||
_ds->bDescriptorType);
|
||
return -EINVAL;
|
||
|
||
case USB_DT_INTERFACE: {
|
||
struct usb_interface_descriptor *ds = (void *)_ds;
|
||
pr_vdebug("interface descriptor\n");
|
||
if (length != sizeof *ds)
|
||
goto inv_length;
|
||
|
||
__entity(INTERFACE, ds->bInterfaceNumber);
|
||
if (ds->iInterface)
|
||
__entity(STRING, ds->iInterface);
|
||
*current_class = ds->bInterfaceClass;
|
||
}
|
||
break;
|
||
|
||
case USB_DT_ENDPOINT: {
|
||
struct usb_endpoint_descriptor *ds = (void *)_ds;
|
||
pr_vdebug("endpoint descriptor\n");
|
||
if (length != USB_DT_ENDPOINT_SIZE &&
|
||
length != USB_DT_ENDPOINT_AUDIO_SIZE)
|
||
goto inv_length;
|
||
__entity(ENDPOINT, ds->bEndpointAddress);
|
||
}
|
||
break;
|
||
|
||
case USB_TYPE_CLASS | 0x01:
|
||
if (*current_class == USB_INTERFACE_CLASS_HID) {
|
||
pr_vdebug("hid descriptor\n");
|
||
if (length != sizeof(struct hid_descriptor))
|
||
goto inv_length;
|
||
break;
|
||
} else if (*current_class == USB_INTERFACE_CLASS_CCID) {
|
||
pr_vdebug("ccid descriptor\n");
|
||
if (length != sizeof(struct ccid_descriptor))
|
||
goto inv_length;
|
||
break;
|
||
} else {
|
||
pr_vdebug("unknown descriptor: %d for class %d\n",
|
||
_ds->bDescriptorType, *current_class);
|
||
return -EINVAL;
|
||
}
|
||
|
||
case USB_DT_OTG:
|
||
if (length != sizeof(struct usb_otg_descriptor))
|
||
goto inv_length;
|
||
break;
|
||
|
||
case USB_DT_INTERFACE_ASSOCIATION: {
|
||
struct usb_interface_assoc_descriptor *ds = (void *)_ds;
|
||
pr_vdebug("interface association descriptor\n");
|
||
if (length != sizeof *ds)
|
||
goto inv_length;
|
||
if (ds->iFunction)
|
||
__entity(STRING, ds->iFunction);
|
||
}
|
||
break;
|
||
|
||
case USB_DT_SS_ENDPOINT_COMP:
|
||
pr_vdebug("EP SS companion descriptor\n");
|
||
if (length != sizeof(struct usb_ss_ep_comp_descriptor))
|
||
goto inv_length;
|
||
break;
|
||
|
||
case USB_DT_OTHER_SPEED_CONFIG:
|
||
case USB_DT_INTERFACE_POWER:
|
||
case USB_DT_DEBUG:
|
||
case USB_DT_SECURITY:
|
||
case USB_DT_CS_RADIO_CONTROL:
|
||
/* TODO */
|
||
pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
|
||
return -EINVAL;
|
||
|
||
default:
|
||
/* We should never be here */
|
||
pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
|
||
return -EINVAL;
|
||
|
||
inv_length:
|
||
pr_vdebug("invalid length: %d (descriptor %d)\n",
|
||
_ds->bLength, _ds->bDescriptorType);
|
||
return -EINVAL;
|
||
}
|
||
|
||
#undef __entity
|
||
#undef __entity_check_DESCRIPTOR
|
||
#undef __entity_check_INTERFACE
|
||
#undef __entity_check_STRING
|
||
#undef __entity_check_ENDPOINT
|
||
|
||
return length;
|
||
}
|
||
|
||
static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
|
||
ffs_entity_callback entity, void *priv)
|
||
{
|
||
const unsigned _len = len;
|
||
unsigned long num = 0;
|
||
int current_class = -1;
|
||
|
||
ENTER();
|
||
|
||
for (;;) {
|
||
int ret;
|
||
|
||
if (num == count)
|
||
data = NULL;
|
||
|
||
/* Record "descriptor" entity */
|
||
ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
|
||
if (unlikely(ret < 0)) {
|
||
pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
|
||
num, ret);
|
||
return ret;
|
||
}
|
||
|
||
if (!data)
|
||
return _len - len;
|
||
|
||
ret = ffs_do_single_desc(data, len, entity, priv,
|
||
¤t_class);
|
||
if (unlikely(ret < 0)) {
|
||
pr_debug("%s returns %d\n", __func__, ret);
|
||
return ret;
|
||
}
|
||
|
||
len -= ret;
|
||
data += ret;
|
||
++num;
|
||
}
|
||
}
|
||
|
||
static int __ffs_data_do_entity(enum ffs_entity_type type,
|
||
u8 *valuep, struct usb_descriptor_header *desc,
|
||
void *priv)
|
||
{
|
||
struct ffs_desc_helper *helper = priv;
|
||
struct usb_endpoint_descriptor *d;
|
||
|
||
ENTER();
|
||
|
||
switch (type) {
|
||
case FFS_DESCRIPTOR:
|
||
break;
|
||
|
||
case FFS_INTERFACE:
|
||
/*
|
||
* Interfaces are indexed from zero so if we
|
||
* encountered interface "n" then there are at least
|
||
* "n+1" interfaces.
|
||
*/
|
||
if (*valuep >= helper->interfaces_count)
|
||
helper->interfaces_count = *valuep + 1;
|
||
break;
|
||
|
||
case FFS_STRING:
|
||
/*
|
||
* Strings are indexed from 1 (0 is reserved
|
||
* for languages list)
|
||
*/
|
||
if (*valuep > helper->ffs->strings_count)
|
||
helper->ffs->strings_count = *valuep;
|
||
break;
|
||
|
||
case FFS_ENDPOINT:
|
||
d = (void *)desc;
|
||
helper->eps_count++;
|
||
if (helper->eps_count >= FFS_MAX_EPS_COUNT)
|
||
return -EINVAL;
|
||
/* Check if descriptors for any speed were already parsed */
|
||
if (!helper->ffs->eps_count && !helper->ffs->interfaces_count)
|
||
helper->ffs->eps_addrmap[helper->eps_count] =
|
||
d->bEndpointAddress;
|
||
else if (helper->ffs->eps_addrmap[helper->eps_count] !=
|
||
d->bEndpointAddress)
|
||
return -EINVAL;
|
||
break;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int __ffs_do_os_desc_header(enum ffs_os_desc_type *next_type,
|
||
struct usb_os_desc_header *desc)
|
||
{
|
||
u16 bcd_version = le16_to_cpu(desc->bcdVersion);
|
||
u16 w_index = le16_to_cpu(desc->wIndex);
|
||
|
||
if (bcd_version != 1) {
|
||
pr_vdebug("unsupported os descriptors version: %d",
|
||
bcd_version);
|
||
return -EINVAL;
|
||
}
|
||
switch (w_index) {
|
||
case 0x4:
|
||
*next_type = FFS_OS_DESC_EXT_COMPAT;
|
||
break;
|
||
case 0x5:
|
||
*next_type = FFS_OS_DESC_EXT_PROP;
|
||
break;
|
||
default:
|
||
pr_vdebug("unsupported os descriptor type: %d", w_index);
|
||
return -EINVAL;
|
||
}
|
||
|
||
return sizeof(*desc);
|
||
}
|
||
|
||
/*
|
||
* Process all extended compatibility/extended property descriptors
|
||
* of a feature descriptor
|
||
*/
|
||
static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
|
||
enum ffs_os_desc_type type,
|
||
u16 feature_count,
|
||
ffs_os_desc_callback entity,
|
||
void *priv,
|
||
struct usb_os_desc_header *h)
|
||
{
|
||
int ret;
|
||
const unsigned _len = len;
|
||
|
||
ENTER();
|
||
|
||
/* loop over all ext compat/ext prop descriptors */
|
||
while (feature_count--) {
|
||
ret = entity(type, h, data, len, priv);
|
||
if (unlikely(ret < 0)) {
|
||
pr_debug("bad OS descriptor, type: %d\n", type);
|
||
return ret;
|
||
}
|
||
data += ret;
|
||
len -= ret;
|
||
}
|
||
return _len - len;
|
||
}
|
||
|
||
/* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
|
||
static int __must_check ffs_do_os_descs(unsigned count,
|
||
char *data, unsigned len,
|
||
ffs_os_desc_callback entity, void *priv)
|
||
{
|
||
const unsigned _len = len;
|
||
unsigned long num = 0;
|
||
|
||
ENTER();
|
||
|
||
for (num = 0; num < count; ++num) {
|
||
int ret;
|
||
enum ffs_os_desc_type type;
|
||
u16 feature_count;
|
||
struct usb_os_desc_header *desc = (void *)data;
|
||
|
||
if (len < sizeof(*desc))
|
||
return -EINVAL;
|
||
|
||
/*
|
||
* Record "descriptor" entity.
|
||
* Process dwLength, bcdVersion, wIndex, get b/wCount.
|
||
* Move the data pointer to the beginning of extended
|
||
* compatibilities proper or extended properties proper
|
||
* portions of the data
|
||
*/
|
||
if (le32_to_cpu(desc->dwLength) > len)
|
||
return -EINVAL;
|
||
|
||
ret = __ffs_do_os_desc_header(&type, desc);
|
||
if (unlikely(ret < 0)) {
|
||
pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
|
||
num, ret);
|
||
return ret;
|
||
}
|
||
/*
|
||
* 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
|
||
*/
|
||
feature_count = le16_to_cpu(desc->wCount);
|
||
if (type == FFS_OS_DESC_EXT_COMPAT &&
|
||
(feature_count > 255 || desc->Reserved))
|
||
return -EINVAL;
|
||
len -= ret;
|
||
data += ret;
|
||
|
||
/*
|
||
* Process all function/property descriptors
|
||
* of this Feature Descriptor
|
||
*/
|
||
ret = ffs_do_single_os_desc(data, len, type,
|
||
feature_count, entity, priv, desc);
|
||
if (unlikely(ret < 0)) {
|
||
pr_debug("%s returns %d\n", __func__, ret);
|
||
return ret;
|
||
}
|
||
|
||
len -= ret;
|
||
data += ret;
|
||
}
|
||
return _len - len;
|
||
}
|
||
|
||
/**
|
||
* Validate contents of the buffer from userspace related to OS descriptors.
|
||
*/
|
||
static int __ffs_data_do_os_desc(enum ffs_os_desc_type type,
|
||
struct usb_os_desc_header *h, void *data,
|
||
unsigned len, void *priv)
|
||
{
|
||
struct ffs_data *ffs = priv;
|
||
u8 length;
|
||
|
||
ENTER();
|
||
|
||
switch (type) {
|
||
case FFS_OS_DESC_EXT_COMPAT: {
|
||
struct usb_ext_compat_desc *d = data;
|
||
int i;
|
||
|
||
if (len < sizeof(*d) ||
|
||
d->bFirstInterfaceNumber >= ffs->interfaces_count)
|
||
return -EINVAL;
|
||
if (d->Reserved1 != 1) {
|
||
/*
|
||
* According to the spec, Reserved1 must be set to 1
|
||
* but older kernels incorrectly rejected non-zero
|
||
* values. We fix it here to avoid returning EINVAL
|
||
* in response to values we used to accept.
|
||
*/
|
||
pr_debug("usb_ext_compat_desc::Reserved1 forced to 1\n");
|
||
d->Reserved1 = 1;
|
||
}
|
||
for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
|
||
if (d->Reserved2[i])
|
||
return -EINVAL;
|
||
|
||
length = sizeof(struct usb_ext_compat_desc);
|
||
}
|
||
break;
|
||
case FFS_OS_DESC_EXT_PROP: {
|
||
struct usb_ext_prop_desc *d = data;
|
||
u32 type, pdl;
|
||
u16 pnl;
|
||
|
||
if (len < sizeof(*d) || h->interface >= ffs->interfaces_count)
|
||
return -EINVAL;
|
||
length = le32_to_cpu(d->dwSize);
|
||
if (len < length)
|
||
return -EINVAL;
|
||
type = le32_to_cpu(d->dwPropertyDataType);
|
||
if (type < USB_EXT_PROP_UNICODE ||
|
||
type > USB_EXT_PROP_UNICODE_MULTI) {
|
||
pr_vdebug("unsupported os descriptor property type: %d",
|
||
type);
|
||
return -EINVAL;
|
||
}
|
||
pnl = le16_to_cpu(d->wPropertyNameLength);
|
||
if (length < 14 + pnl) {
|
||
pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
|
||
length, pnl, type);
|
||
return -EINVAL;
|
||
}
|
||
pdl = le32_to_cpu(*(__le32 *)((u8 *)data + 10 + pnl));
|
||
if (length != 14 + pnl + pdl) {
|
||
pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
|
||
length, pnl, pdl, type);
|
||
return -EINVAL;
|
||
}
|
||
++ffs->ms_os_descs_ext_prop_count;
|
||
/* property name reported to the host as "WCHAR"s */
|
||
ffs->ms_os_descs_ext_prop_name_len += pnl * 2;
|
||
ffs->ms_os_descs_ext_prop_data_len += pdl;
|
||
}
|
||
break;
|
||
default:
|
||
pr_vdebug("unknown descriptor: %d\n", type);
|
||
return -EINVAL;
|
||
}
|
||
return length;
|
||
}
|
||
|
||
static int __ffs_data_got_descs(struct ffs_data *ffs,
|
||
char *const _data, size_t len)
|
||
{
|
||
char *data = _data, *raw_descs;
|
||
unsigned os_descs_count = 0, counts[3], flags;
|
||
int ret = -EINVAL, i;
|
||
struct ffs_desc_helper helper;
|
||
|
||
ENTER();
|
||
|
||
if (get_unaligned_le32(data + 4) != len)
|
||
goto error;
|
||
|
||
switch (get_unaligned_le32(data)) {
|
||
case FUNCTIONFS_DESCRIPTORS_MAGIC:
|
||
flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
|
||
data += 8;
|
||
len -= 8;
|
||
break;
|
||
case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
|
||
flags = get_unaligned_le32(data + 8);
|
||
ffs->user_flags = flags;
|
||
if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
|
||
FUNCTIONFS_HAS_HS_DESC |
|
||
FUNCTIONFS_HAS_SS_DESC |
|
||
FUNCTIONFS_HAS_MS_OS_DESC |
|
||
FUNCTIONFS_VIRTUAL_ADDR |
|
||
FUNCTIONFS_EVENTFD |
|
||
FUNCTIONFS_ALL_CTRL_RECIP |
|
||
FUNCTIONFS_CONFIG0_SETUP)) {
|
||
ret = -ENOSYS;
|
||
goto error;
|
||
}
|
||
data += 12;
|
||
len -= 12;
|
||
break;
|
||
default:
|
||
goto error;
|
||
}
|
||
|
||
if (flags & FUNCTIONFS_EVENTFD) {
|
||
if (len < 4)
|
||
goto error;
|
||
ffs->ffs_eventfd =
|
||
eventfd_ctx_fdget((int)get_unaligned_le32(data));
|
||
if (IS_ERR(ffs->ffs_eventfd)) {
|
||
ret = PTR_ERR(ffs->ffs_eventfd);
|
||
ffs->ffs_eventfd = NULL;
|
||
goto error;
|
||
}
|
||
data += 4;
|
||
len -= 4;
|
||
}
|
||
|
||
/* Read fs_count, hs_count and ss_count (if present) */
|
||
for (i = 0; i < 3; ++i) {
|
||
if (!(flags & (1 << i))) {
|
||
counts[i] = 0;
|
||
} else if (len < 4) {
|
||
goto error;
|
||
} else {
|
||
counts[i] = get_unaligned_le32(data);
|
||
data += 4;
|
||
len -= 4;
|
||
}
|
||
}
|
||
if (flags & (1 << i)) {
|
||
if (len < 4) {
|
||
goto error;
|
||
}
|
||
os_descs_count = get_unaligned_le32(data);
|
||
data += 4;
|
||
len -= 4;
|
||
};
|
||
|
||
/* Read descriptors */
|
||
raw_descs = data;
|
||
helper.ffs = ffs;
|
||
for (i = 0; i < 3; ++i) {
|
||
if (!counts[i])
|
||
continue;
|
||
helper.interfaces_count = 0;
|
||
helper.eps_count = 0;
|
||
ret = ffs_do_descs(counts[i], data, len,
|
||
__ffs_data_do_entity, &helper);
|
||
if (ret < 0)
|
||
goto error;
|
||
if (!ffs->eps_count && !ffs->interfaces_count) {
|
||
ffs->eps_count = helper.eps_count;
|
||
ffs->interfaces_count = helper.interfaces_count;
|
||
} else {
|
||
if (ffs->eps_count != helper.eps_count) {
|
||
ret = -EINVAL;
|
||
goto error;
|
||
}
|
||
if (ffs->interfaces_count != helper.interfaces_count) {
|
||
ret = -EINVAL;
|
||
goto error;
|
||
}
|
||
}
|
||
data += ret;
|
||
len -= ret;
|
||
}
|
||
if (os_descs_count) {
|
||
ret = ffs_do_os_descs(os_descs_count, data, len,
|
||
__ffs_data_do_os_desc, ffs);
|
||
if (ret < 0)
|
||
goto error;
|
||
data += ret;
|
||
len -= ret;
|
||
}
|
||
|
||
if (raw_descs == data || len) {
|
||
ret = -EINVAL;
|
||
goto error;
|
||
}
|
||
|
||
ffs->raw_descs_data = _data;
|
||
ffs->raw_descs = raw_descs;
|
||
ffs->raw_descs_length = data - raw_descs;
|
||
ffs->fs_descs_count = counts[0];
|
||
ffs->hs_descs_count = counts[1];
|
||
ffs->ss_descs_count = counts[2];
|
||
ffs->ms_os_descs_count = os_descs_count;
|
||
|
||
return 0;
|
||
|
||
error:
|
||
kfree(_data);
|
||
return ret;
|
||
}
|
||
|
||
static int __ffs_data_got_strings(struct ffs_data *ffs,
|
||
char *const _data, size_t len)
|
||
{
|
||
u32 str_count, needed_count, lang_count;
|
||
struct usb_gadget_strings **stringtabs, *t;
|
||
const char *data = _data;
|
||
struct usb_string *s;
|
||
|
||
ENTER();
|
||
|
||
if (unlikely(len < 16 ||
|
||
get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
|
||
get_unaligned_le32(data + 4) != len))
|
||
goto error;
|
||
str_count = get_unaligned_le32(data + 8);
|
||
lang_count = get_unaligned_le32(data + 12);
|
||
|
||
/* if one is zero the other must be zero */
|
||
if (unlikely(!str_count != !lang_count))
|
||
goto error;
|
||
|
||
/* Do we have at least as many strings as descriptors need? */
|
||
needed_count = ffs->strings_count;
|
||
if (unlikely(str_count < needed_count))
|
||
goto error;
|
||
|
||
/*
|
||
* If we don't need any strings just return and free all
|
||
* memory.
|
||
*/
|
||
if (!needed_count) {
|
||
kfree(_data);
|
||
return 0;
|
||
}
|
||
|
||
/* Allocate everything in one chunk so there's less maintenance. */
|
||
{
|
||
unsigned i = 0;
|
||
vla_group(d);
|
||
vla_item(d, struct usb_gadget_strings *, stringtabs,
|
||
lang_count + 1);
|
||
vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
|
||
vla_item(d, struct usb_string, strings,
|
||
lang_count*(needed_count+1));
|
||
|
||
char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
|
||
|
||
if (unlikely(!vlabuf)) {
|
||
kfree(_data);
|
||
return -ENOMEM;
|
||
}
|
||
|
||
/* Initialize the VLA pointers */
|
||
stringtabs = vla_ptr(vlabuf, d, stringtabs);
|
||
t = vla_ptr(vlabuf, d, stringtab);
|
||
i = lang_count;
|
||
do {
|
||
*stringtabs++ = t++;
|
||
} while (--i);
|
||
*stringtabs = NULL;
|
||
|
||
/* stringtabs = vlabuf = d_stringtabs for later kfree */
|
||
stringtabs = vla_ptr(vlabuf, d, stringtabs);
|
||
t = vla_ptr(vlabuf, d, stringtab);
|
||
s = vla_ptr(vlabuf, d, strings);
|
||
}
|
||
|
||
/* For each language */
|
||
data += 16;
|
||
len -= 16;
|
||
|
||
do { /* lang_count > 0 so we can use do-while */
|
||
unsigned needed = needed_count;
|
||
|
||
if (unlikely(len < 3))
|
||
goto error_free;
|
||
t->language = get_unaligned_le16(data);
|
||
t->strings = s;
|
||
++t;
|
||
|
||
data += 2;
|
||
len -= 2;
|
||
|
||
/* For each string */
|
||
do { /* str_count > 0 so we can use do-while */
|
||
size_t length = strnlen(data, len);
|
||
|
||
if (unlikely(length == len))
|
||
goto error_free;
|
||
|
||
/*
|
||
* User may provide more strings then we need,
|
||
* if that's the case we simply ignore the
|
||
* rest
|
||
*/
|
||
if (likely(needed)) {
|
||
/*
|
||
* s->id will be set while adding
|
||
* function to configuration so for
|
||
* now just leave garbage here.
|
||
*/
|
||
s->s = data;
|
||
--needed;
|
||
++s;
|
||
}
|
||
|
||
data += length + 1;
|
||
len -= length + 1;
|
||
} while (--str_count);
|
||
|
||
s->id = 0; /* terminator */
|
||
s->s = NULL;
|
||
++s;
|
||
|
||
} while (--lang_count);
|
||
|
||
/* Some garbage left? */
|
||
if (unlikely(len))
|
||
goto error_free;
|
||
|
||
/* Done! */
|
||
ffs->stringtabs = stringtabs;
|
||
ffs->raw_strings = _data;
|
||
|
||
return 0;
|
||
|
||
error_free:
|
||
kfree(stringtabs);
|
||
error:
|
||
kfree(_data);
|
||
return -EINVAL;
|
||
}
|
||
|
||
|
||
/* Events handling and management *******************************************/
|
||
|
||
static void __ffs_event_add(struct ffs_data *ffs,
|
||
enum usb_functionfs_event_type type)
|
||
{
|
||
enum usb_functionfs_event_type rem_type1, rem_type2 = type;
|
||
int neg = 0;
|
||
|
||
/*
|
||
* Abort any unhandled setup
|
||
*
|
||
* We do not need to worry about some cmpxchg() changing value
|
||
* of ffs->setup_state without holding the lock because when
|
||
* state is FFS_SETUP_PENDING cmpxchg() in several places in
|
||
* the source does nothing.
|
||
*/
|
||
if (ffs->setup_state == FFS_SETUP_PENDING)
|
||
ffs->setup_state = FFS_SETUP_CANCELLED;
|
||
|
||
/*
|
||
* Logic of this function guarantees that there are at most four pending
|
||
* evens on ffs->ev.types queue. This is important because the queue
|
||
* has space for four elements only and __ffs_ep0_read_events function
|
||
* depends on that limit as well. If more event types are added, those
|
||
* limits have to be revisited or guaranteed to still hold.
|
||
*/
|
||
switch (type) {
|
||
case FUNCTIONFS_RESUME:
|
||
rem_type2 = FUNCTIONFS_SUSPEND;
|
||
/* FALL THROUGH */
|
||
case FUNCTIONFS_SUSPEND:
|
||
case FUNCTIONFS_SETUP:
|
||
rem_type1 = type;
|
||
/* Discard all similar events */
|
||
break;
|
||
|
||
case FUNCTIONFS_BIND:
|
||
case FUNCTIONFS_UNBIND:
|
||
case FUNCTIONFS_DISABLE:
|
||
case FUNCTIONFS_ENABLE:
|
||
/* Discard everything other then power management. */
|
||
rem_type1 = FUNCTIONFS_SUSPEND;
|
||
rem_type2 = FUNCTIONFS_RESUME;
|
||
neg = 1;
|
||
break;
|
||
|
||
default:
|
||
WARN(1, "%d: unknown event, this should not happen\n", type);
|
||
return;
|
||
}
|
||
|
||
{
|
||
u8 *ev = ffs->ev.types, *out = ev;
|
||
unsigned n = ffs->ev.count;
|
||
for (; n; --n, ++ev)
|
||
if ((*ev == rem_type1 || *ev == rem_type2) == neg)
|
||
*out++ = *ev;
|
||
else
|
||
pr_vdebug("purging event %d\n", *ev);
|
||
ffs->ev.count = out - ffs->ev.types;
|
||
}
|
||
|
||
pr_vdebug("adding event %d\n", type);
|
||
ffs->ev.types[ffs->ev.count++] = type;
|
||
wake_up_locked(&ffs->ev.waitq);
|
||
if (ffs->ffs_eventfd)
|
||
eventfd_signal(ffs->ffs_eventfd, 1);
|
||
}
|
||
|
||
static void ffs_event_add(struct ffs_data *ffs,
|
||
enum usb_functionfs_event_type type)
|
||
{
|
||
unsigned long flags;
|
||
spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
|
||
__ffs_event_add(ffs, type);
|
||
spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
|
||
}
|
||
|
||
/* Bind/unbind USB function hooks *******************************************/
|
||
|
||
static int ffs_ep_addr2idx(struct ffs_data *ffs, u8 endpoint_address)
|
||
{
|
||
int i;
|
||
|
||
for (i = 1; i < ARRAY_SIZE(ffs->eps_addrmap); ++i)
|
||
if (ffs->eps_addrmap[i] == endpoint_address)
|
||
return i;
|
||
return -ENOENT;
|
||
}
|
||
|
||
static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
|
||
struct usb_descriptor_header *desc,
|
||
void *priv)
|
||
{
|
||
struct usb_endpoint_descriptor *ds = (void *)desc;
|
||
struct ffs_function *func = priv;
|
||
struct ffs_ep *ffs_ep;
|
||
unsigned ep_desc_id;
|
||
int idx;
|
||
static const char *speed_names[] = { "full", "high", "super" };
|
||
|
||
if (type != FFS_DESCRIPTOR)
|
||
return 0;
|
||
|
||
/*
|
||
* If ss_descriptors is not NULL, we are reading super speed
|
||
* descriptors; if hs_descriptors is not NULL, we are reading high
|
||
* speed descriptors; otherwise, we are reading full speed
|
||
* descriptors.
|
||
*/
|
||
if (func->function.ss_descriptors) {
|
||
ep_desc_id = 2;
|
||
func->function.ss_descriptors[(long)valuep] = desc;
|
||
} else if (func->function.hs_descriptors) {
|
||
ep_desc_id = 1;
|
||
func->function.hs_descriptors[(long)valuep] = desc;
|
||
} else {
|
||
ep_desc_id = 0;
|
||
func->function.fs_descriptors[(long)valuep] = desc;
|
||
}
|
||
|
||
if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
|
||
return 0;
|
||
|
||
idx = ffs_ep_addr2idx(func->ffs, ds->bEndpointAddress) - 1;
|
||
if (idx < 0)
|
||
return idx;
|
||
|
||
ffs_ep = func->eps + idx;
|
||
|
||
if (unlikely(ffs_ep->descs[ep_desc_id])) {
|
||
pr_err("two %sspeed descriptors for EP %d\n",
|
||
speed_names[ep_desc_id],
|
||
ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
|
||
return -EINVAL;
|
||
}
|
||
ffs_ep->descs[ep_desc_id] = ds;
|
||
|
||
ffs_dump_mem(": Original ep desc", ds, ds->bLength);
|
||
if (ffs_ep->ep) {
|
||
ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
|
||
if (!ds->wMaxPacketSize)
|
||
ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
|
||
} else {
|
||
struct usb_request *req;
|
||
struct usb_ep *ep;
|
||
u8 bEndpointAddress;
|
||
u16 wMaxPacketSize;
|
||
|
||
/*
|
||
* We back up bEndpointAddress because autoconfig overwrites
|
||
* it with physical endpoint address.
|
||
*/
|
||
bEndpointAddress = ds->bEndpointAddress;
|
||
/*
|
||
* We back up wMaxPacketSize because autoconfig treats
|
||
* endpoint descriptors as if they were full speed.
|
||
*/
|
||
wMaxPacketSize = ds->wMaxPacketSize;
|
||
pr_vdebug("autoconfig\n");
|
||
ep = usb_ep_autoconfig(func->gadget, ds);
|
||
if (unlikely(!ep))
|
||
return -ENOTSUPP;
|
||
ep->driver_data = func->eps + idx;
|
||
|
||
req = usb_ep_alloc_request(ep, GFP_KERNEL);
|
||
if (unlikely(!req))
|
||
return -ENOMEM;
|
||
|
||
ffs_ep->ep = ep;
|
||
ffs_ep->req = req;
|
||
func->eps_revmap[ds->bEndpointAddress &
|
||
USB_ENDPOINT_NUMBER_MASK] = idx + 1;
|
||
/*
|
||
* If we use virtual address mapping, we restore
|
||
* original bEndpointAddress value.
|
||
*/
|
||
if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
|
||
ds->bEndpointAddress = bEndpointAddress;
|
||
/*
|
||
* Restore wMaxPacketSize which was potentially
|
||
* overwritten by autoconfig.
|
||
*/
|
||
ds->wMaxPacketSize = wMaxPacketSize;
|
||
}
|
||
ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
|
||
struct usb_descriptor_header *desc,
|
||
void *priv)
|
||
{
|
||
struct ffs_function *func = priv;
|
||
unsigned idx;
|
||
u8 newValue;
|
||
|
||
switch (type) {
|
||
default:
|
||
case FFS_DESCRIPTOR:
|
||
/* Handled in previous pass by __ffs_func_bind_do_descs() */
|
||
return 0;
|
||
|
||
case FFS_INTERFACE:
|
||
idx = *valuep;
|
||
if (func->interfaces_nums[idx] < 0) {
|
||
int id = usb_interface_id(func->conf, &func->function);
|
||
if (unlikely(id < 0))
|
||
return id;
|
||
func->interfaces_nums[idx] = id;
|
||
}
|
||
newValue = func->interfaces_nums[idx];
|
||
break;
|
||
|
||
case FFS_STRING:
|
||
/* String' IDs are allocated when fsf_data is bound to cdev */
|
||
newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
|
||
break;
|
||
|
||
case FFS_ENDPOINT:
|
||
/*
|
||
* USB_DT_ENDPOINT are handled in
|
||
* __ffs_func_bind_do_descs().
|
||
*/
|
||
if (desc->bDescriptorType == USB_DT_ENDPOINT)
|
||
return 0;
|
||
|
||
idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
|
||
if (unlikely(!func->eps[idx].ep))
|
||
return -EINVAL;
|
||
|
||
{
|
||
struct usb_endpoint_descriptor **descs;
|
||
descs = func->eps[idx].descs;
|
||
newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
|
||
}
|
||
break;
|
||
}
|
||
|
||
pr_vdebug("%02x -> %02x\n", *valuep, newValue);
|
||
*valuep = newValue;
|
||
return 0;
|
||
}
|
||
|
||
static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
|
||
struct usb_os_desc_header *h, void *data,
|
||
unsigned len, void *priv)
|
||
{
|
||
struct ffs_function *func = priv;
|
||
u8 length = 0;
|
||
|
||
switch (type) {
|
||
case FFS_OS_DESC_EXT_COMPAT: {
|
||
struct usb_ext_compat_desc *desc = data;
|
||
struct usb_os_desc_table *t;
|
||
|
||
t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
|
||
t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
|
||
memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
|
||
ARRAY_SIZE(desc->CompatibleID) +
|
||
ARRAY_SIZE(desc->SubCompatibleID));
|
||
length = sizeof(*desc);
|
||
}
|
||
break;
|
||
case FFS_OS_DESC_EXT_PROP: {
|
||
struct usb_ext_prop_desc *desc = data;
|
||
struct usb_os_desc_table *t;
|
||
struct usb_os_desc_ext_prop *ext_prop;
|
||
char *ext_prop_name;
|
||
char *ext_prop_data;
|
||
|
||
t = &func->function.os_desc_table[h->interface];
|
||
t->if_id = func->interfaces_nums[h->interface];
|
||
|
||
ext_prop = func->ffs->ms_os_descs_ext_prop_avail;
|
||
func->ffs->ms_os_descs_ext_prop_avail += sizeof(*ext_prop);
|
||
|
||
ext_prop->type = le32_to_cpu(desc->dwPropertyDataType);
|
||
ext_prop->name_len = le16_to_cpu(desc->wPropertyNameLength);
|
||
ext_prop->data_len = le32_to_cpu(*(__le32 *)
|
||
usb_ext_prop_data_len_ptr(data, ext_prop->name_len));
|
||
length = ext_prop->name_len + ext_prop->data_len + 14;
|
||
|
||
ext_prop_name = func->ffs->ms_os_descs_ext_prop_name_avail;
|
||
func->ffs->ms_os_descs_ext_prop_name_avail +=
|
||
ext_prop->name_len;
|
||
|
||
ext_prop_data = func->ffs->ms_os_descs_ext_prop_data_avail;
|
||
func->ffs->ms_os_descs_ext_prop_data_avail +=
|
||
ext_prop->data_len;
|
||
memcpy(ext_prop_data,
|
||
usb_ext_prop_data_ptr(data, ext_prop->name_len),
|
||
ext_prop->data_len);
|
||
/* unicode data reported to the host as "WCHAR"s */
|
||
switch (ext_prop->type) {
|
||
case USB_EXT_PROP_UNICODE:
|
||
case USB_EXT_PROP_UNICODE_ENV:
|
||
case USB_EXT_PROP_UNICODE_LINK:
|
||
case USB_EXT_PROP_UNICODE_MULTI:
|
||
ext_prop->data_len *= 2;
|
||
break;
|
||
}
|
||
ext_prop->data = ext_prop_data;
|
||
|
||
memcpy(ext_prop_name, usb_ext_prop_name_ptr(data),
|
||
ext_prop->name_len);
|
||
/* property name reported to the host as "WCHAR"s */
|
||
ext_prop->name_len *= 2;
|
||
ext_prop->name = ext_prop_name;
|
||
|
||
t->os_desc->ext_prop_len +=
|
||
ext_prop->name_len + ext_prop->data_len + 14;
|
||
++t->os_desc->ext_prop_count;
|
||
list_add_tail(&ext_prop->entry, &t->os_desc->ext_prop);
|
||
}
|
||
break;
|
||
default:
|
||
pr_vdebug("unknown descriptor: %d\n", type);
|
||
}
|
||
|
||
return length;
|
||
}
|
||
|
||
static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
|
||
struct usb_configuration *c)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
struct f_fs_opts *ffs_opts =
|
||
container_of(f->fi, struct f_fs_opts, func_inst);
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
/*
|
||
* Legacy gadget triggers binding in functionfs_ready_callback,
|
||
* which already uses locking; taking the same lock here would
|
||
* cause a deadlock.
|
||
*
|
||
* Configfs-enabled gadgets however do need ffs_dev_lock.
|
||
*/
|
||
if (!ffs_opts->no_configfs)
|
||
ffs_dev_lock();
|
||
ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
|
||
func->ffs = ffs_opts->dev->ffs_data;
|
||
if (!ffs_opts->no_configfs)
|
||
ffs_dev_unlock();
|
||
if (ret)
|
||
return ERR_PTR(ret);
|
||
|
||
func->conf = c;
|
||
func->gadget = c->cdev->gadget;
|
||
|
||
/*
|
||
* in drivers/usb/gadget/configfs.c:configfs_composite_bind()
|
||
* configurations are bound in sequence with list_for_each_entry,
|
||
* in each configuration its functions are bound in sequence
|
||
* with list_for_each_entry, so we assume no race condition
|
||
* with regard to ffs_opts->bound access
|
||
*/
|
||
if (!ffs_opts->refcnt) {
|
||
ret = functionfs_bind(func->ffs, c->cdev);
|
||
if (ret)
|
||
return ERR_PTR(ret);
|
||
}
|
||
ffs_opts->refcnt++;
|
||
func->function.strings = func->ffs->stringtabs;
|
||
|
||
return ffs_opts;
|
||
}
|
||
|
||
static int _ffs_func_bind(struct usb_configuration *c,
|
||
struct usb_function *f)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
struct ffs_data *ffs = func->ffs;
|
||
|
||
const int full = !!func->ffs->fs_descs_count;
|
||
const int high = !!func->ffs->hs_descs_count;
|
||
const int super = !!func->ffs->ss_descs_count;
|
||
|
||
int fs_len, hs_len, ss_len, ret, i;
|
||
struct ffs_ep *eps_ptr;
|
||
|
||
/* Make it a single chunk, less management later on */
|
||
vla_group(d);
|
||
vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
|
||
vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
|
||
full ? ffs->fs_descs_count + 1 : 0);
|
||
vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
|
||
high ? ffs->hs_descs_count + 1 : 0);
|
||
vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
|
||
super ? ffs->ss_descs_count + 1 : 0);
|
||
vla_item_with_sz(d, short, inums, ffs->interfaces_count);
|
||
vla_item_with_sz(d, struct usb_os_desc_table, os_desc_table,
|
||
c->cdev->use_os_string ? ffs->interfaces_count : 0);
|
||
vla_item_with_sz(d, char[16], ext_compat,
|
||
c->cdev->use_os_string ? ffs->interfaces_count : 0);
|
||
vla_item_with_sz(d, struct usb_os_desc, os_desc,
|
||
c->cdev->use_os_string ? ffs->interfaces_count : 0);
|
||
vla_item_with_sz(d, struct usb_os_desc_ext_prop, ext_prop,
|
||
ffs->ms_os_descs_ext_prop_count);
|
||
vla_item_with_sz(d, char, ext_prop_name,
|
||
ffs->ms_os_descs_ext_prop_name_len);
|
||
vla_item_with_sz(d, char, ext_prop_data,
|
||
ffs->ms_os_descs_ext_prop_data_len);
|
||
vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
|
||
char *vlabuf;
|
||
|
||
ENTER();
|
||
|
||
/* Has descriptors only for speeds gadget does not support */
|
||
if (unlikely(!(full | high | super)))
|
||
return -ENOTSUPP;
|
||
|
||
/* Allocate a single chunk, less management later on */
|
||
vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
|
||
if (unlikely(!vlabuf))
|
||
return -ENOMEM;
|
||
|
||
ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
|
||
ffs->ms_os_descs_ext_prop_name_avail =
|
||
vla_ptr(vlabuf, d, ext_prop_name);
|
||
ffs->ms_os_descs_ext_prop_data_avail =
|
||
vla_ptr(vlabuf, d, ext_prop_data);
|
||
|
||
/* Copy descriptors */
|
||
memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
|
||
ffs->raw_descs_length);
|
||
|
||
memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
|
||
eps_ptr = vla_ptr(vlabuf, d, eps);
|
||
for (i = 0; i < ffs->eps_count; i++)
|
||
eps_ptr[i].num = -1;
|
||
|
||
/* Save pointers
|
||
* d_eps == vlabuf, func->eps used to kfree vlabuf later
|
||
*/
|
||
func->eps = vla_ptr(vlabuf, d, eps);
|
||
func->interfaces_nums = vla_ptr(vlabuf, d, inums);
|
||
|
||
/*
|
||
* Go through all the endpoint descriptors and allocate
|
||
* endpoints first, so that later we can rewrite the endpoint
|
||
* numbers without worrying that it may be described later on.
|
||
*/
|
||
if (likely(full)) {
|
||
func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
|
||
fs_len = ffs_do_descs(ffs->fs_descs_count,
|
||
vla_ptr(vlabuf, d, raw_descs),
|
||
d_raw_descs__sz,
|
||
__ffs_func_bind_do_descs, func);
|
||
if (unlikely(fs_len < 0)) {
|
||
ret = fs_len;
|
||
goto error;
|
||
}
|
||
} else {
|
||
fs_len = 0;
|
||
}
|
||
|
||
if (likely(high)) {
|
||
func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
|
||
hs_len = ffs_do_descs(ffs->hs_descs_count,
|
||
vla_ptr(vlabuf, d, raw_descs) + fs_len,
|
||
d_raw_descs__sz - fs_len,
|
||
__ffs_func_bind_do_descs, func);
|
||
if (unlikely(hs_len < 0)) {
|
||
ret = hs_len;
|
||
goto error;
|
||
}
|
||
} else {
|
||
hs_len = 0;
|
||
}
|
||
|
||
if (likely(super)) {
|
||
func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
|
||
ss_len = ffs_do_descs(ffs->ss_descs_count,
|
||
vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
|
||
d_raw_descs__sz - fs_len - hs_len,
|
||
__ffs_func_bind_do_descs, func);
|
||
if (unlikely(ss_len < 0)) {
|
||
ret = ss_len;
|
||
goto error;
|
||
}
|
||
} else {
|
||
ss_len = 0;
|
||
}
|
||
|
||
/*
|
||
* Now handle interface numbers allocation and interface and
|
||
* endpoint numbers rewriting. We can do that in one go
|
||
* now.
|
||
*/
|
||
ret = ffs_do_descs(ffs->fs_descs_count +
|
||
(high ? ffs->hs_descs_count : 0) +
|
||
(super ? ffs->ss_descs_count : 0),
|
||
vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
|
||
__ffs_func_bind_do_nums, func);
|
||
if (unlikely(ret < 0))
|
||
goto error;
|
||
|
||
func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
|
||
if (c->cdev->use_os_string) {
|
||
for (i = 0; i < ffs->interfaces_count; ++i) {
|
||
struct usb_os_desc *desc;
|
||
|
||
desc = func->function.os_desc_table[i].os_desc =
|
||
vla_ptr(vlabuf, d, os_desc) +
|
||
i * sizeof(struct usb_os_desc);
|
||
desc->ext_compat_id =
|
||
vla_ptr(vlabuf, d, ext_compat) + i * 16;
|
||
INIT_LIST_HEAD(&desc->ext_prop);
|
||
}
|
||
ret = ffs_do_os_descs(ffs->ms_os_descs_count,
|
||
vla_ptr(vlabuf, d, raw_descs) +
|
||
fs_len + hs_len + ss_len,
|
||
d_raw_descs__sz - fs_len - hs_len -
|
||
ss_len,
|
||
__ffs_func_bind_do_os_desc, func);
|
||
if (unlikely(ret < 0))
|
||
goto error;
|
||
}
|
||
func->function.os_desc_n =
|
||
c->cdev->use_os_string ? ffs->interfaces_count : 0;
|
||
|
||
/* And we're done */
|
||
ffs_event_add(ffs, FUNCTIONFS_BIND);
|
||
return 0;
|
||
|
||
error:
|
||
/* XXX Do we need to release all claimed endpoints here? */
|
||
return ret;
|
||
}
|
||
|
||
static int ffs_func_bind(struct usb_configuration *c,
|
||
struct usb_function *f)
|
||
{
|
||
struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
int ret;
|
||
|
||
if (IS_ERR(ffs_opts))
|
||
return PTR_ERR(ffs_opts);
|
||
|
||
ret = _ffs_func_bind(c, f);
|
||
if (ret && !--ffs_opts->refcnt)
|
||
functionfs_unbind(func->ffs);
|
||
|
||
return ret;
|
||
}
|
||
|
||
|
||
/* Other USB function hooks *************************************************/
|
||
|
||
static void ffs_reset_work(struct work_struct *work)
|
||
{
|
||
struct ffs_data *ffs = container_of(work,
|
||
struct ffs_data, reset_work);
|
||
ffs_data_reset(ffs);
|
||
}
|
||
|
||
static int ffs_func_set_alt(struct usb_function *f,
|
||
unsigned interface, unsigned alt)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
struct ffs_data *ffs = func->ffs;
|
||
int ret = 0, intf;
|
||
|
||
if (alt != (unsigned)-1) {
|
||
intf = ffs_func_revmap_intf(func, interface);
|
||
if (unlikely(intf < 0))
|
||
return intf;
|
||
}
|
||
|
||
if (ffs->func)
|
||
ffs_func_eps_disable(ffs->func);
|
||
|
||
if (ffs->state == FFS_DEACTIVATED) {
|
||
ffs->state = FFS_CLOSING;
|
||
INIT_WORK(&ffs->reset_work, ffs_reset_work);
|
||
schedule_work(&ffs->reset_work);
|
||
return -ENODEV;
|
||
}
|
||
|
||
if (ffs->state != FFS_ACTIVE)
|
||
return -ENODEV;
|
||
|
||
if (alt == (unsigned)-1) {
|
||
ffs->func = NULL;
|
||
ffs_event_add(ffs, FUNCTIONFS_DISABLE);
|
||
return 0;
|
||
}
|
||
|
||
ffs->func = func;
|
||
ret = ffs_func_eps_enable(func);
|
||
if (likely(ret >= 0))
|
||
ffs_event_add(ffs, FUNCTIONFS_ENABLE);
|
||
return ret;
|
||
}
|
||
|
||
static void ffs_func_disable(struct usb_function *f)
|
||
{
|
||
ffs_func_set_alt(f, 0, (unsigned)-1);
|
||
}
|
||
|
||
static int ffs_func_setup(struct usb_function *f,
|
||
const struct usb_ctrlrequest *creq)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
struct ffs_data *ffs = func->ffs;
|
||
unsigned long flags;
|
||
int ret;
|
||
|
||
ENTER();
|
||
|
||
pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
|
||
pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
|
||
pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
|
||
pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
|
||
pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
|
||
|
||
/*
|
||
* Most requests directed to interface go through here
|
||
* (notable exceptions are set/get interface) so we need to
|
||
* handle them. All other either handled by composite or
|
||
* passed to usb_configuration->setup() (if one is set). No
|
||
* matter, we will handle requests directed to endpoint here
|
||
* as well (as it's straightforward). Other request recipient
|
||
* types are only handled when the user flag FUNCTIONFS_ALL_CTRL_RECIP
|
||
* is being used.
|
||
*/
|
||
if (ffs->state != FFS_ACTIVE)
|
||
return -ENODEV;
|
||
|
||
switch (creq->bRequestType & USB_RECIP_MASK) {
|
||
case USB_RECIP_INTERFACE:
|
||
ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
|
||
if (unlikely(ret < 0))
|
||
return ret;
|
||
break;
|
||
|
||
case USB_RECIP_ENDPOINT:
|
||
ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
|
||
if (unlikely(ret < 0))
|
||
return ret;
|
||
if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
|
||
ret = func->ffs->eps_addrmap[ret];
|
||
break;
|
||
|
||
default:
|
||
if (func->ffs->user_flags & FUNCTIONFS_ALL_CTRL_RECIP)
|
||
ret = le16_to_cpu(creq->wIndex);
|
||
else
|
||
return -EOPNOTSUPP;
|
||
}
|
||
|
||
spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
|
||
ffs->ev.setup = *creq;
|
||
ffs->ev.setup.wIndex = cpu_to_le16(ret);
|
||
__ffs_event_add(ffs, FUNCTIONFS_SETUP);
|
||
spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
|
||
|
||
return creq->wLength == 0 ? USB_GADGET_DELAYED_STATUS : 0;
|
||
}
|
||
|
||
static bool ffs_func_req_match(struct usb_function *f,
|
||
const struct usb_ctrlrequest *creq,
|
||
bool config0)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
|
||
if (config0 && !(func->ffs->user_flags & FUNCTIONFS_CONFIG0_SETUP))
|
||
return false;
|
||
|
||
switch (creq->bRequestType & USB_RECIP_MASK) {
|
||
case USB_RECIP_INTERFACE:
|
||
return (ffs_func_revmap_intf(func,
|
||
le16_to_cpu(creq->wIndex)) >= 0);
|
||
case USB_RECIP_ENDPOINT:
|
||
return (ffs_func_revmap_ep(func,
|
||
le16_to_cpu(creq->wIndex)) >= 0);
|
||
default:
|
||
return (bool) (func->ffs->user_flags &
|
||
FUNCTIONFS_ALL_CTRL_RECIP);
|
||
}
|
||
}
|
||
|
||
static void ffs_func_suspend(struct usb_function *f)
|
||
{
|
||
ENTER();
|
||
ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
|
||
}
|
||
|
||
static void ffs_func_resume(struct usb_function *f)
|
||
{
|
||
ENTER();
|
||
ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
|
||
}
|
||
|
||
|
||
/* Endpoint and interface numbers reverse mapping ***************************/
|
||
|
||
static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
|
||
{
|
||
num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
|
||
return num ? num : -EDOM;
|
||
}
|
||
|
||
static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
|
||
{
|
||
short *nums = func->interfaces_nums;
|
||
unsigned count = func->ffs->interfaces_count;
|
||
|
||
for (; count; --count, ++nums) {
|
||
if (*nums >= 0 && *nums == intf)
|
||
return nums - func->interfaces_nums;
|
||
}
|
||
|
||
return -EDOM;
|
||
}
|
||
|
||
|
||
/* Devices management *******************************************************/
|
||
|
||
static LIST_HEAD(ffs_devices);
|
||
|
||
static struct ffs_dev *_ffs_do_find_dev(const char *name)
|
||
{
|
||
struct ffs_dev *dev;
|
||
|
||
if (!name)
|
||
return NULL;
|
||
|
||
list_for_each_entry(dev, &ffs_devices, entry) {
|
||
if (strcmp(dev->name, name) == 0)
|
||
return dev;
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/*
|
||
* ffs_lock must be taken by the caller of this function
|
||
*/
|
||
static struct ffs_dev *_ffs_get_single_dev(void)
|
||
{
|
||
struct ffs_dev *dev;
|
||
|
||
if (list_is_singular(&ffs_devices)) {
|
||
dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
|
||
if (dev->single)
|
||
return dev;
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/*
|
||
* ffs_lock must be taken by the caller of this function
|
||
*/
|
||
static struct ffs_dev *_ffs_find_dev(const char *name)
|
||
{
|
||
struct ffs_dev *dev;
|
||
|
||
dev = _ffs_get_single_dev();
|
||
if (dev)
|
||
return dev;
|
||
|
||
return _ffs_do_find_dev(name);
|
||
}
|
||
|
||
/* Configfs support *********************************************************/
|
||
|
||
static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
|
||
{
|
||
return container_of(to_config_group(item), struct f_fs_opts,
|
||
func_inst.group);
|
||
}
|
||
|
||
static void ffs_attr_release(struct config_item *item)
|
||
{
|
||
struct f_fs_opts *opts = to_ffs_opts(item);
|
||
|
||
usb_put_function_instance(&opts->func_inst);
|
||
}
|
||
|
||
static struct configfs_item_operations ffs_item_ops = {
|
||
.release = ffs_attr_release,
|
||
};
|
||
|
||
static const struct config_item_type ffs_func_type = {
|
||
.ct_item_ops = &ffs_item_ops,
|
||
.ct_owner = THIS_MODULE,
|
||
};
|
||
|
||
|
||
/* Function registration interface ******************************************/
|
||
|
||
static void ffs_free_inst(struct usb_function_instance *f)
|
||
{
|
||
struct f_fs_opts *opts;
|
||
|
||
opts = to_f_fs_opts(f);
|
||
ffs_dev_lock();
|
||
_ffs_free_dev(opts->dev);
|
||
ffs_dev_unlock();
|
||
kfree(opts);
|
||
}
|
||
|
||
static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
|
||
{
|
||
if (strlen(name) >= sizeof_field(struct ffs_dev, name))
|
||
return -ENAMETOOLONG;
|
||
return ffs_name_dev(to_f_fs_opts(fi)->dev, name);
|
||
}
|
||
|
||
static struct usb_function_instance *ffs_alloc_inst(void)
|
||
{
|
||
struct f_fs_opts *opts;
|
||
struct ffs_dev *dev;
|
||
|
||
opts = kzalloc(sizeof(*opts), GFP_KERNEL);
|
||
if (!opts)
|
||
return ERR_PTR(-ENOMEM);
|
||
|
||
opts->func_inst.set_inst_name = ffs_set_inst_name;
|
||
opts->func_inst.free_func_inst = ffs_free_inst;
|
||
ffs_dev_lock();
|
||
dev = _ffs_alloc_dev();
|
||
ffs_dev_unlock();
|
||
if (IS_ERR(dev)) {
|
||
kfree(opts);
|
||
return ERR_CAST(dev);
|
||
}
|
||
opts->dev = dev;
|
||
dev->opts = opts;
|
||
|
||
config_group_init_type_name(&opts->func_inst.group, "",
|
||
&ffs_func_type);
|
||
return &opts->func_inst;
|
||
}
|
||
|
||
static void ffs_free(struct usb_function *f)
|
||
{
|
||
kfree(ffs_func_from_usb(f));
|
||
}
|
||
|
||
static void ffs_func_unbind(struct usb_configuration *c,
|
||
struct usb_function *f)
|
||
{
|
||
struct ffs_function *func = ffs_func_from_usb(f);
|
||
struct ffs_data *ffs = func->ffs;
|
||
struct f_fs_opts *opts =
|
||
container_of(f->fi, struct f_fs_opts, func_inst);
|
||
struct ffs_ep *ep = func->eps;
|
||
unsigned count = ffs->eps_count;
|
||
unsigned long flags;
|
||
|
||
ENTER();
|
||
if (ffs->func == func) {
|
||
ffs_func_eps_disable(func);
|
||
ffs->func = NULL;
|
||
}
|
||
|
||
if (!--opts->refcnt)
|
||
functionfs_unbind(ffs);
|
||
|
||
/* cleanup after autoconfig */
|
||
spin_lock_irqsave(&func->ffs->eps_lock, flags);
|
||
while (count--) {
|
||
if (ep->ep && ep->req)
|
||
usb_ep_free_request(ep->ep, ep->req);
|
||
ep->req = NULL;
|
||
++ep;
|
||
}
|
||
spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
|
||
kfree(func->eps);
|
||
func->eps = NULL;
|
||
/*
|
||
* eps, descriptors and interfaces_nums are allocated in the
|
||
* same chunk so only one free is required.
|
||
*/
|
||
func->function.fs_descriptors = NULL;
|
||
func->function.hs_descriptors = NULL;
|
||
func->function.ss_descriptors = NULL;
|
||
func->interfaces_nums = NULL;
|
||
|
||
ffs_event_add(ffs, FUNCTIONFS_UNBIND);
|
||
}
|
||
|
||
static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
|
||
{
|
||
struct ffs_function *func;
|
||
|
||
ENTER();
|
||
|
||
func = kzalloc(sizeof(*func), GFP_KERNEL);
|
||
if (unlikely(!func))
|
||
return ERR_PTR(-ENOMEM);
|
||
|
||
func->function.name = "Function FS Gadget";
|
||
|
||
func->function.bind = ffs_func_bind;
|
||
func->function.unbind = ffs_func_unbind;
|
||
func->function.set_alt = ffs_func_set_alt;
|
||
func->function.disable = ffs_func_disable;
|
||
func->function.setup = ffs_func_setup;
|
||
func->function.req_match = ffs_func_req_match;
|
||
func->function.suspend = ffs_func_suspend;
|
||
func->function.resume = ffs_func_resume;
|
||
func->function.free_func = ffs_free;
|
||
|
||
return &func->function;
|
||
}
|
||
|
||
/*
|
||
* ffs_lock must be taken by the caller of this function
|
||
*/
|
||
static struct ffs_dev *_ffs_alloc_dev(void)
|
||
{
|
||
struct ffs_dev *dev;
|
||
int ret;
|
||
|
||
if (_ffs_get_single_dev())
|
||
return ERR_PTR(-EBUSY);
|
||
|
||
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
||
if (!dev)
|
||
return ERR_PTR(-ENOMEM);
|
||
|
||
if (list_empty(&ffs_devices)) {
|
||
ret = functionfs_init();
|
||
if (ret) {
|
||
kfree(dev);
|
||
return ERR_PTR(ret);
|
||
}
|
||
}
|
||
|
||
list_add(&dev->entry, &ffs_devices);
|
||
|
||
return dev;
|
||
}
|
||
|
||
int ffs_name_dev(struct ffs_dev *dev, const char *name)
|
||
{
|
||
struct ffs_dev *existing;
|
||
int ret = 0;
|
||
|
||
ffs_dev_lock();
|
||
|
||
existing = _ffs_do_find_dev(name);
|
||
if (!existing)
|
||
strlcpy(dev->name, name, ARRAY_SIZE(dev->name));
|
||
else if (existing != dev)
|
||
ret = -EBUSY;
|
||
|
||
ffs_dev_unlock();
|
||
|
||
return ret;
|
||
}
|
||
EXPORT_SYMBOL_GPL(ffs_name_dev);
|
||
|
||
int ffs_single_dev(struct ffs_dev *dev)
|
||
{
|
||
int ret;
|
||
|
||
ret = 0;
|
||
ffs_dev_lock();
|
||
|
||
if (!list_is_singular(&ffs_devices))
|
||
ret = -EBUSY;
|
||
else
|
||
dev->single = true;
|
||
|
||
ffs_dev_unlock();
|
||
return ret;
|
||
}
|
||
EXPORT_SYMBOL_GPL(ffs_single_dev);
|
||
|
||
/*
|
||
* ffs_lock must be taken by the caller of this function
|
||
*/
|
||
static void _ffs_free_dev(struct ffs_dev *dev)
|
||
{
|
||
list_del(&dev->entry);
|
||
|
||
/* Clear the private_data pointer to stop incorrect dev access */
|
||
if (dev->ffs_data)
|
||
dev->ffs_data->private_data = NULL;
|
||
|
||
kfree(dev);
|
||
if (list_empty(&ffs_devices))
|
||
functionfs_cleanup();
|
||
}
|
||
|
||
static void *ffs_acquire_dev(const char *dev_name)
|
||
{
|
||
struct ffs_dev *ffs_dev;
|
||
|
||
ENTER();
|
||
ffs_dev_lock();
|
||
|
||
ffs_dev = _ffs_find_dev(dev_name);
|
||
if (!ffs_dev)
|
||
ffs_dev = ERR_PTR(-ENOENT);
|
||
else if (ffs_dev->mounted)
|
||
ffs_dev = ERR_PTR(-EBUSY);
|
||
else if (ffs_dev->ffs_acquire_dev_callback &&
|
||
ffs_dev->ffs_acquire_dev_callback(ffs_dev))
|
||
ffs_dev = ERR_PTR(-ENOENT);
|
||
else
|
||
ffs_dev->mounted = true;
|
||
|
||
ffs_dev_unlock();
|
||
return ffs_dev;
|
||
}
|
||
|
||
static void ffs_release_dev(struct ffs_data *ffs_data)
|
||
{
|
||
struct ffs_dev *ffs_dev;
|
||
|
||
ENTER();
|
||
ffs_dev_lock();
|
||
|
||
ffs_dev = ffs_data->private_data;
|
||
if (ffs_dev) {
|
||
ffs_dev->mounted = false;
|
||
|
||
if (ffs_dev->ffs_release_dev_callback)
|
||
ffs_dev->ffs_release_dev_callback(ffs_dev);
|
||
}
|
||
|
||
ffs_dev_unlock();
|
||
}
|
||
|
||
static int ffs_ready(struct ffs_data *ffs)
|
||
{
|
||
struct ffs_dev *ffs_obj;
|
||
int ret = 0;
|
||
|
||
ENTER();
|
||
ffs_dev_lock();
|
||
|
||
ffs_obj = ffs->private_data;
|
||
if (!ffs_obj) {
|
||
ret = -EINVAL;
|
||
goto done;
|
||
}
|
||
if (WARN_ON(ffs_obj->desc_ready)) {
|
||
ret = -EBUSY;
|
||
goto done;
|
||
}
|
||
|
||
ffs_obj->desc_ready = true;
|
||
ffs_obj->ffs_data = ffs;
|
||
|
||
if (ffs_obj->ffs_ready_callback) {
|
||
ret = ffs_obj->ffs_ready_callback(ffs);
|
||
if (ret)
|
||
goto done;
|
||
}
|
||
|
||
set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
|
||
done:
|
||
ffs_dev_unlock();
|
||
return ret;
|
||
}
|
||
|
||
static void ffs_closed(struct ffs_data *ffs)
|
||
{
|
||
struct ffs_dev *ffs_obj;
|
||
struct f_fs_opts *opts;
|
||
struct config_item *ci;
|
||
|
||
ENTER();
|
||
ffs_dev_lock();
|
||
|
||
ffs_obj = ffs->private_data;
|
||
if (!ffs_obj)
|
||
goto done;
|
||
|
||
ffs_obj->desc_ready = false;
|
||
ffs_obj->ffs_data = NULL;
|
||
|
||
if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags) &&
|
||
ffs_obj->ffs_closed_callback)
|
||
ffs_obj->ffs_closed_callback(ffs);
|
||
|
||
if (ffs_obj->opts)
|
||
opts = ffs_obj->opts;
|
||
else
|
||
goto done;
|
||
|
||
if (opts->no_configfs || !opts->func_inst.group.cg_item.ci_parent
|
||
|| !kref_read(&opts->func_inst.group.cg_item.ci_kref))
|
||
goto done;
|
||
|
||
ci = opts->func_inst.group.cg_item.ci_parent->ci_parent;
|
||
ffs_dev_unlock();
|
||
|
||
if (test_bit(FFS_FL_BOUND, &ffs->flags))
|
||
unregister_gadget_item(ci);
|
||
return;
|
||
done:
|
||
ffs_dev_unlock();
|
||
}
|
||
|
||
/* Misc helper functions ****************************************************/
|
||
|
||
static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
|
||
{
|
||
return nonblock
|
||
? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
|
||
: mutex_lock_interruptible(mutex);
|
||
}
|
||
|
||
static char *ffs_prepare_buffer(const char __user *buf, size_t len)
|
||
{
|
||
char *data;
|
||
|
||
if (unlikely(!len))
|
||
return NULL;
|
||
|
||
data = kmalloc(len, GFP_KERNEL);
|
||
if (unlikely(!data))
|
||
return ERR_PTR(-ENOMEM);
|
||
|
||
if (unlikely(copy_from_user(data, buf, len))) {
|
||
kfree(data);
|
||
return ERR_PTR(-EFAULT);
|
||
}
|
||
|
||
pr_vdebug("Buffer from user space:\n");
|
||
ffs_dump_mem("", data, len);
|
||
|
||
return data;
|
||
}
|
||
|
||
DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
|
||
MODULE_LICENSE("GPL");
|
||
MODULE_AUTHOR("Michal Nazarewicz");
|