91 строка
2.2 KiB
C
91 строка
2.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/net.h>
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#include <linux/uio.h>
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#include <net/sock.h>
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#include <linux/nospec.h>
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#include "rsrc.h"
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#define IO_NOTIF_SPLICE_BATCH 32
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#define IORING_MAX_NOTIF_SLOTS (1U << 15)
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struct io_notif_data {
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struct file *file;
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struct ubuf_info uarg;
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unsigned long account_pages;
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};
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struct io_notif_slot {
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/*
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* Current/active notifier. A slot holds only one active notifier at a
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* time and keeps one reference to it. Flush releases the reference and
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* lazily replaces it with a new notifier.
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*/
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struct io_kiocb *notif;
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/*
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* Default ->user_data for this slot notifiers CQEs
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*/
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u64 tag;
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/*
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* Notifiers of a slot live in generations, we create a new notifier
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* only after flushing the previous one. Track the sequential number
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* for all notifiers and copy it into notifiers's cqe->cflags
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*/
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u32 seq;
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};
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int io_notif_register(struct io_ring_ctx *ctx,
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void __user *arg, unsigned int size);
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int io_notif_unregister(struct io_ring_ctx *ctx);
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void io_notif_slot_flush(struct io_notif_slot *slot);
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struct io_kiocb *io_alloc_notif(struct io_ring_ctx *ctx,
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struct io_notif_slot *slot);
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static inline struct io_notif_data *io_notif_to_data(struct io_kiocb *notif)
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{
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return io_kiocb_to_cmd(notif, struct io_notif_data);
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}
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static inline struct io_kiocb *io_get_notif(struct io_ring_ctx *ctx,
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struct io_notif_slot *slot)
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{
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if (!slot->notif)
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slot->notif = io_alloc_notif(ctx, slot);
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return slot->notif;
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}
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static inline struct io_notif_slot *io_get_notif_slot(struct io_ring_ctx *ctx,
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unsigned idx)
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__must_hold(&ctx->uring_lock)
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{
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if (idx >= ctx->nr_notif_slots)
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return NULL;
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idx = array_index_nospec(idx, ctx->nr_notif_slots);
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return &ctx->notif_slots[idx];
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}
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static inline void io_notif_slot_flush_submit(struct io_notif_slot *slot,
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unsigned int issue_flags)
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{
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io_notif_slot_flush(slot);
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}
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static inline int io_notif_account_mem(struct io_kiocb *notif, unsigned len)
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{
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struct io_ring_ctx *ctx = notif->ctx;
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struct io_notif_data *nd = io_notif_to_data(notif);
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unsigned nr_pages = (len >> PAGE_SHIFT) + 2;
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int ret;
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if (ctx->user) {
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ret = __io_account_mem(ctx->user, nr_pages);
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if (ret)
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return ret;
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nd->account_pages += nr_pages;
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}
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return 0;
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}
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