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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/fs/ocfs2/file.c

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28 KiB
C
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/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* file.c
*
* File open, close, extend, truncate
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/uio.h>
#define MLOG_MASK_PREFIX ML_INODE
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "aops.h"
#include "dir.h"
#include "dlmglue.h"
#include "extent_map.h"
#include "file.h"
#include "sysfile.h"
#include "inode.h"
#include "journal.h"
#include "mmap.h"
#include "suballoc.h"
#include "super.h"
#include "buffer_head_io.h"
static int ocfs2_sync_inode(struct inode *inode)
{
filemap_fdatawrite(inode->i_mapping);
return sync_mapping_buffers(inode->i_mapping);
}
static int ocfs2_file_open(struct inode *inode, struct file *file)
{
int status;
int mode = file->f_flags;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
file->f_dentry->d_name.len, file->f_dentry->d_name.name);
spin_lock(&oi->ip_lock);
/* Check that the inode hasn't been wiped from disk by another
* node. If it hasn't then we're safe as long as we hold the
* spin lock until our increment of open count. */
if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_DELETED) {
spin_unlock(&oi->ip_lock);
status = -ENOENT;
goto leave;
}
if (mode & O_DIRECT)
oi->ip_flags |= OCFS2_INODE_OPEN_DIRECT;
oi->ip_open_count++;
spin_unlock(&oi->ip_lock);
status = 0;
leave:
mlog_exit(status);
return status;
}
static int ocfs2_file_release(struct inode *inode, struct file *file)
{
struct ocfs2_inode_info *oi = OCFS2_I(inode);
mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
file->f_dentry->d_name.len,
file->f_dentry->d_name.name);
spin_lock(&oi->ip_lock);
if (!--oi->ip_open_count)
oi->ip_flags &= ~OCFS2_INODE_OPEN_DIRECT;
spin_unlock(&oi->ip_lock);
mlog_exit(0);
return 0;
}
static int ocfs2_sync_file(struct file *file,
struct dentry *dentry,
int datasync)
{
int err = 0;
journal_t *journal;
struct inode *inode = dentry->d_inode;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
mlog_entry("(0x%p, 0x%p, %d, '%.*s')\n", file, dentry, datasync,
dentry->d_name.len, dentry->d_name.name);
err = ocfs2_sync_inode(dentry->d_inode);
if (err)
goto bail;
journal = osb->journal->j_journal;
err = journal_force_commit(journal);
bail:
mlog_exit(err);
return (err < 0) ? -EIO : 0;
}
int ocfs2_set_inode_size(struct ocfs2_journal_handle *handle,
struct inode *inode,
struct buffer_head *fe_bh,
u64 new_i_size)
{
int status;
mlog_entry_void();
i_size_write(inode, new_i_size);
inode->i_blocks = ocfs2_align_bytes_to_sectors(new_i_size);
inode->i_ctime = inode->i_mtime = CURRENT_TIME;
status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bail:
mlog_exit(status);
return status;
}
static int ocfs2_simple_size_update(struct inode *inode,
struct buffer_head *di_bh,
u64 new_i_size)
{
int ret;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_journal_handle *handle = NULL;
handle = ocfs2_start_trans(osb, NULL,
OCFS2_INODE_UPDATE_CREDITS);
if (handle == NULL) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
ret = ocfs2_set_inode_size(handle, inode, di_bh,
new_i_size);
if (ret < 0)
mlog_errno(ret);
ocfs2_commit_trans(handle);
out:
return ret;
}
static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb,
struct inode *inode,
struct buffer_head *fe_bh,
u64 new_i_size)
{
int status;
struct ocfs2_journal_handle *handle;
mlog_entry_void();
/* TODO: This needs to actually orphan the inode in this
* transaction. */
handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
mlog_errno(status);
goto out;
}
status = ocfs2_set_inode_size(handle, inode, fe_bh, new_i_size);
if (status < 0)
mlog_errno(status);
ocfs2_commit_trans(handle);
out:
mlog_exit(status);
return status;
}
static int ocfs2_truncate_file(struct inode *inode,
struct buffer_head *di_bh,
u64 new_i_size)
{
int status = 0;
struct ocfs2_dinode *fe = NULL;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_truncate_context *tc = NULL;
mlog_entry("(inode = %"MLFu64", new_i_size = %"MLFu64"\n",
OCFS2_I(inode)->ip_blkno, new_i_size);
truncate_inode_pages(inode->i_mapping, new_i_size);
fe = (struct ocfs2_dinode *) di_bh->b_data;
if (!OCFS2_IS_VALID_DINODE(fe)) {
OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
status = -EIO;
goto bail;
}
mlog_bug_on_msg(le64_to_cpu(fe->i_size) != i_size_read(inode),
"Inode %"MLFu64", inode i_size = %lld != di "
"i_size = %"MLFu64", i_flags = 0x%x\n",
OCFS2_I(inode)->ip_blkno,
i_size_read(inode),
le64_to_cpu(fe->i_size), le32_to_cpu(fe->i_flags));
if (new_i_size > le64_to_cpu(fe->i_size)) {
mlog(0, "asked to truncate file with size (%"MLFu64") "
"to size (%"MLFu64")!\n",
le64_to_cpu(fe->i_size), new_i_size);
status = -EINVAL;
mlog_errno(status);
goto bail;
}
mlog(0, "inode %"MLFu64", i_size = %"MLFu64", new_i_size = %"MLFu64"\n",
le64_to_cpu(fe->i_blkno), le64_to_cpu(fe->i_size), new_i_size);
/* lets handle the simple truncate cases before doing any more
* cluster locking. */
if (new_i_size == le64_to_cpu(fe->i_size))
goto bail;
if (le32_to_cpu(fe->i_clusters) ==
ocfs2_clusters_for_bytes(osb->sb, new_i_size)) {
mlog(0, "fe->i_clusters = %u, so we do a simple truncate\n",
fe->i_clusters);
/* No allocation change is required, so lets fast path
* this truncate. */
status = ocfs2_simple_size_update(inode, di_bh, new_i_size);
if (status < 0)
mlog_errno(status);
goto bail;
}
/* This forces other nodes to sync and drop their pages */
status = ocfs2_data_lock(inode, 1);
if (status < 0) {
mlog_errno(status);
goto bail;
}
ocfs2_data_unlock(inode, 1);
/* alright, we're going to need to do a full blown alloc size
* change. Orphan the inode so that recovery can complete the
* truncate if necessary. This does the task of marking
* i_size. */
status = ocfs2_orphan_for_truncate(osb, inode, di_bh, new_i_size);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = ocfs2_prepare_truncate(osb, inode, di_bh, &tc);
if (status < 0) {
mlog_errno(status);
goto bail;
}
status = ocfs2_commit_truncate(osb, inode, di_bh, tc);
if (status < 0) {
mlog_errno(status);
goto bail;
}
/* TODO: orphan dir cleanup here. */
bail:
mlog_exit(status);
return status;
}
/*
* extend allocation only here.
* we'll update all the disk stuff, and oip->alloc_size
*
* expect stuff to be locked, a transaction started and enough data /
* metadata reservations in the contexts.
*
* Will return -EAGAIN, and a reason if a restart is needed.
* If passed in, *reason will always be set, even in error.
*/
int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
struct inode *inode,
u32 clusters_to_add,
struct buffer_head *fe_bh,
struct ocfs2_journal_handle *handle,
struct ocfs2_alloc_context *data_ac,
struct ocfs2_alloc_context *meta_ac,
enum ocfs2_alloc_restarted *reason_ret)
{
int status = 0;
int free_extents;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
enum ocfs2_alloc_restarted reason = RESTART_NONE;
u32 bit_off, num_bits;
u64 block;
BUG_ON(!clusters_to_add);
free_extents = ocfs2_num_free_extents(osb, inode, fe);
if (free_extents < 0) {
status = free_extents;
mlog_errno(status);
goto leave;
}
/* there are two cases which could cause us to EAGAIN in the
* we-need-more-metadata case:
* 1) we haven't reserved *any*
* 2) we are so fragmented, we've needed to add metadata too
* many times. */
if (!free_extents && !meta_ac) {
mlog(0, "we haven't reserved any metadata!\n");
status = -EAGAIN;
reason = RESTART_META;
goto leave;
} else if ((!free_extents)
&& (ocfs2_alloc_context_bits_left(meta_ac)
< ocfs2_extend_meta_needed(fe))) {
mlog(0, "filesystem is really fragmented...\n");
status = -EAGAIN;
reason = RESTART_META;
goto leave;
}
status = ocfs2_claim_clusters(osb, handle, data_ac, 1,
&bit_off, &num_bits);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto leave;
}
BUG_ON(num_bits > clusters_to_add);
/* reserve our write early -- insert_extent may update the inode */
status = ocfs2_journal_access(handle, inode, fe_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto leave;
}
block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
mlog(0, "Allocating %u clusters at block %u for inode %"MLFu64"\n",
num_bits, bit_off, OCFS2_I(inode)->ip_blkno);
status = ocfs2_insert_extent(osb, handle, inode, fe_bh, block,
num_bits, meta_ac);
if (status < 0) {
mlog_errno(status);
goto leave;
}
le32_add_cpu(&fe->i_clusters, num_bits);
spin_lock(&OCFS2_I(inode)->ip_lock);
OCFS2_I(inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
spin_unlock(&OCFS2_I(inode)->ip_lock);
status = ocfs2_journal_dirty(handle, fe_bh);
if (status < 0) {
mlog_errno(status);
goto leave;
}
clusters_to_add -= num_bits;
if (clusters_to_add) {
mlog(0, "need to alloc once more, clusters = %u, wanted = "
"%u\n", fe->i_clusters, clusters_to_add);
status = -EAGAIN;
reason = RESTART_TRANS;
}
leave:
mlog_exit(status);
if (reason_ret)
*reason_ret = reason;
return status;
}
static int ocfs2_extend_allocation(struct inode *inode,
u32 clusters_to_add)
{
int status = 0;
int restart_func = 0;
int drop_alloc_sem = 0;
int credits, num_free_extents;
u32 prev_clusters;
struct buffer_head *bh = NULL;
struct ocfs2_dinode *fe = NULL;
struct ocfs2_journal_handle *handle = NULL;
struct ocfs2_alloc_context *data_ac = NULL;
struct ocfs2_alloc_context *meta_ac = NULL;
enum ocfs2_alloc_restarted why;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
mlog_entry("(clusters_to_add = %u)\n", clusters_to_add);
status = ocfs2_read_block(osb, OCFS2_I(inode)->ip_blkno, &bh,
OCFS2_BH_CACHED, inode);
if (status < 0) {
mlog_errno(status);
goto leave;
}
fe = (struct ocfs2_dinode *) bh->b_data;
if (!OCFS2_IS_VALID_DINODE(fe)) {
OCFS2_RO_ON_INVALID_DINODE(inode->i_sb, fe);
status = -EIO;
goto leave;
}
restart_all:
BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
mlog(0, "extend inode %"MLFu64", i_size = %lld, fe->i_clusters = %u, "
"clusters_to_add = %u\n",
OCFS2_I(inode)->ip_blkno, i_size_read(inode),
fe->i_clusters, clusters_to_add);
handle = ocfs2_alloc_handle(osb);
if (handle == NULL) {
status = -ENOMEM;
mlog_errno(status);
goto leave;
}
num_free_extents = ocfs2_num_free_extents(osb,
inode,
fe);
if (num_free_extents < 0) {
status = num_free_extents;
mlog_errno(status);
goto leave;
}
if (!num_free_extents) {
status = ocfs2_reserve_new_metadata(osb,
handle,
fe,
&meta_ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto leave;
}
}
status = ocfs2_reserve_clusters(osb,
handle,
clusters_to_add,
&data_ac);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto leave;
}
/* blocks peope in read/write from reading our allocation
* until we're done changing it. We depend on i_mutex to block
* other extend/truncate calls while we're here. Ordering wrt
* start_trans is important here -- always do it before! */
down_write(&OCFS2_I(inode)->ip_alloc_sem);
drop_alloc_sem = 1;
credits = ocfs2_calc_extend_credits(osb->sb, fe, clusters_to_add);
handle = ocfs2_start_trans(osb, handle, credits);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
handle = NULL;
mlog_errno(status);
goto leave;
}
restarted_transaction:
/* reserve a write to the file entry early on - that we if we
* run out of credits in the allocation path, we can still
* update i_size. */
status = ocfs2_journal_access(handle, inode, bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto leave;
}
prev_clusters = OCFS2_I(inode)->ip_clusters;
status = ocfs2_do_extend_allocation(osb,
inode,
clusters_to_add,
bh,
handle,
data_ac,
meta_ac,
&why);
if ((status < 0) && (status != -EAGAIN)) {
if (status != -ENOSPC)
mlog_errno(status);
goto leave;
}
status = ocfs2_journal_dirty(handle, bh);
if (status < 0) {
mlog_errno(status);
goto leave;
}
spin_lock(&OCFS2_I(inode)->ip_lock);
clusters_to_add -= (OCFS2_I(inode)->ip_clusters - prev_clusters);
spin_unlock(&OCFS2_I(inode)->ip_lock);
if (why != RESTART_NONE && clusters_to_add) {
if (why == RESTART_META) {
mlog(0, "restarting function.\n");
restart_func = 1;
} else {
BUG_ON(why != RESTART_TRANS);
mlog(0, "restarting transaction.\n");
/* TODO: This can be more intelligent. */
credits = ocfs2_calc_extend_credits(osb->sb,
fe,
clusters_to_add);
status = ocfs2_extend_trans(handle, credits);
if (status < 0) {
/* handle still has to be committed at
* this point. */
status = -ENOMEM;
mlog_errno(status);
goto leave;
}
goto restarted_transaction;
}
}
mlog(0, "fe: i_clusters = %u, i_size=%"MLFu64"\n",
fe->i_clusters, fe->i_size);
mlog(0, "inode: ip_clusters=%u, i_size=%lld\n",
OCFS2_I(inode)->ip_clusters, i_size_read(inode));
leave:
if (drop_alloc_sem) {
up_write(&OCFS2_I(inode)->ip_alloc_sem);
drop_alloc_sem = 0;
}
if (handle) {
ocfs2_commit_trans(handle);
handle = NULL;
}
if (data_ac) {
ocfs2_free_alloc_context(data_ac);
data_ac = NULL;
}
if (meta_ac) {
ocfs2_free_alloc_context(meta_ac);
meta_ac = NULL;
}
if ((!status) && restart_func) {
restart_func = 0;
goto restart_all;
}
if (bh) {
brelse(bh);
bh = NULL;
}
mlog_exit(status);
return status;
}
/* Some parts of this taken from generic_cont_expand, which turned out
* to be too fragile to do exactly what we need without us having to
* worry about recursive locking in ->commit_write(). */
static int ocfs2_write_zero_page(struct inode *inode,
u64 size)
{
struct address_space *mapping = inode->i_mapping;
struct page *page;
unsigned long index;
unsigned int offset;
struct ocfs2_journal_handle *handle = NULL;
int ret;
offset = (size & (PAGE_CACHE_SIZE-1)); /* Within page */
/* ugh. in prepare/commit_write, if from==to==start of block, we
** skip the prepare. make sure we never send an offset for the start
** of a block
*/
if ((offset & (inode->i_sb->s_blocksize - 1)) == 0) {
offset++;
}
index = size >> PAGE_CACHE_SHIFT;
page = grab_cache_page(mapping, index);
if (!page) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
ret = ocfs2_prepare_write(NULL, page, offset, offset);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock;
}
if (ocfs2_should_order_data(inode)) {
handle = ocfs2_start_walk_page_trans(inode, page, offset,
offset);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
handle = NULL;
goto out_unlock;
}
}
/* must not update i_size! */
ret = block_commit_write(page, offset, offset);
if (ret < 0)
mlog_errno(ret);
else
ret = 0;
if (handle)
ocfs2_commit_trans(handle);
out_unlock:
unlock_page(page);
page_cache_release(page);
out:
return ret;
}
static int ocfs2_zero_extend(struct inode *inode,
u64 zero_to_size)
{
int ret = 0;
u64 start_off;
struct super_block *sb = inode->i_sb;
start_off = ocfs2_align_bytes_to_blocks(sb, i_size_read(inode));
while (start_off < zero_to_size) {
ret = ocfs2_write_zero_page(inode, start_off);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
start_off += sb->s_blocksize;
}
out:
return ret;
}
static int ocfs2_extend_file(struct inode *inode,
struct buffer_head *di_bh,
u64 new_i_size)
{
int ret = 0;
u32 clusters_to_add;
/* setattr sometimes calls us like this. */
if (new_i_size == 0)
goto out;
if (i_size_read(inode) == new_i_size)
goto out;
BUG_ON(new_i_size < i_size_read(inode));
clusters_to_add = ocfs2_clusters_for_bytes(inode->i_sb, new_i_size) -
OCFS2_I(inode)->ip_clusters;
if (clusters_to_add) {
ret = ocfs2_extend_allocation(inode, clusters_to_add);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
ret = ocfs2_zero_extend(inode, new_i_size);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
}
/* No allocation required, we just use this helper to
* do a trivial update of i_size. */
ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
out:
return ret;
}
int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
{
int status = 0, size_change;
struct inode *inode = dentry->d_inode;
struct super_block *sb = inode->i_sb;
struct ocfs2_super *osb = OCFS2_SB(sb);
struct buffer_head *bh = NULL;
struct ocfs2_journal_handle *handle = NULL;
mlog_entry("(0x%p, '%.*s')\n", dentry,
dentry->d_name.len, dentry->d_name.name);
if (attr->ia_valid & ATTR_MODE)
mlog(0, "mode change: %d\n", attr->ia_mode);
if (attr->ia_valid & ATTR_UID)
mlog(0, "uid change: %d\n", attr->ia_uid);
if (attr->ia_valid & ATTR_GID)
mlog(0, "gid change: %d\n", attr->ia_gid);
if (attr->ia_valid & ATTR_SIZE)
mlog(0, "size change...\n");
if (attr->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME))
mlog(0, "time change...\n");
#define OCFS2_VALID_ATTRS (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME | ATTR_SIZE \
| ATTR_GID | ATTR_UID | ATTR_MODE)
if (!(attr->ia_valid & OCFS2_VALID_ATTRS)) {
mlog(0, "can't handle attrs: 0x%x\n", attr->ia_valid);
return 0;
}
status = inode_change_ok(inode, attr);
if (status)
return status;
size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
if (size_change) {
status = ocfs2_rw_lock(inode, 1);
if (status < 0) {
mlog_errno(status);
goto bail;
}
}
status = ocfs2_meta_lock(inode, NULL, &bh, 1);
if (status < 0) {
if (status != -ENOENT)
mlog_errno(status);
goto bail_unlock_rw;
}
if (size_change && attr->ia_size != i_size_read(inode)) {
if (i_size_read(inode) > attr->ia_size)
status = ocfs2_truncate_file(inode, bh, attr->ia_size);
else
status = ocfs2_extend_file(inode, bh, attr->ia_size);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
status = -ENOSPC;
goto bail_unlock;
}
}
handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
mlog_errno(status);
goto bail_unlock;
}
status = inode_setattr(inode, attr);
if (status < 0) {
mlog_errno(status);
goto bail_commit;
}
status = ocfs2_mark_inode_dirty(handle, inode, bh);
if (status < 0)
mlog_errno(status);
bail_commit:
ocfs2_commit_trans(handle);
bail_unlock:
ocfs2_meta_unlock(inode, 1);
bail_unlock_rw:
if (size_change)
ocfs2_rw_unlock(inode, 1);
bail:
if (bh)
brelse(bh);
mlog_exit(status);
return status;
}
int ocfs2_getattr(struct vfsmount *mnt,
struct dentry *dentry,
struct kstat *stat)
{
struct inode *inode = dentry->d_inode;
struct super_block *sb = dentry->d_inode->i_sb;
struct ocfs2_super *osb = sb->s_fs_info;
int err;
mlog_entry_void();
err = ocfs2_inode_revalidate(dentry);
if (err) {
if (err != -ENOENT)
mlog_errno(err);
goto bail;
}
generic_fillattr(inode, stat);
/* We set the blksize from the cluster size for performance */
stat->blksize = osb->s_clustersize;
bail:
mlog_exit(err);
return err;
}
static int ocfs2_write_remove_suid(struct inode *inode)
{
int ret;
struct buffer_head *bh = NULL;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
struct ocfs2_journal_handle *handle;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_dinode *di;
mlog_entry("(Inode %"MLFu64", mode 0%o)\n", oi->ip_blkno,
inode->i_mode);
handle = ocfs2_start_trans(osb, NULL, OCFS2_INODE_UPDATE_CREDITS);
if (handle == NULL) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
ret = ocfs2_read_block(osb, oi->ip_blkno, &bh, OCFS2_BH_CACHED, inode);
if (ret < 0) {
mlog_errno(ret);
goto out_trans;
}
ret = ocfs2_journal_access(handle, inode, bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (ret < 0) {
mlog_errno(ret);
goto out_bh;
}
inode->i_mode &= ~S_ISUID;
if ((inode->i_mode & S_ISGID) && (inode->i_mode & S_IXGRP))
inode->i_mode &= ~S_ISGID;
di = (struct ocfs2_dinode *) bh->b_data;
di->i_mode = cpu_to_le16(inode->i_mode);
ret = ocfs2_journal_dirty(handle, bh);
if (ret < 0)
mlog_errno(ret);
out_bh:
brelse(bh);
out_trans:
ocfs2_commit_trans(handle);
out:
mlog_exit(ret);
return ret;
}
static inline int ocfs2_write_should_remove_suid(struct inode *inode)
{
mode_t mode = inode->i_mode;
if (!capable(CAP_FSETID)) {
if (unlikely(mode & S_ISUID))
return 1;
if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
return 1;
}
return 0;
}
static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
const char __user *buf,
size_t count,
loff_t pos)
{
struct iovec local_iov = { .iov_base = (void __user *)buf,
.iov_len = count };
int ret, rw_level = -1, meta_level = -1, have_alloc_sem = 0;
u32 clusters;
struct file *filp = iocb->ki_filp;
struct inode *inode = filp->f_dentry->d_inode;
loff_t newsize, saved_pos;
mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
(unsigned int)count,
filp->f_dentry->d_name.len,
filp->f_dentry->d_name.name);
/* happy write of zero bytes */
if (count == 0)
return 0;
if (!inode) {
mlog(0, "bad inode\n");
return -EIO;
}
mutex_lock(&inode->i_mutex);
/* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */
if (filp->f_flags & O_DIRECT) {
have_alloc_sem = 1;
down_read(&inode->i_alloc_sem);
}
/* concurrent O_DIRECT writes are allowed */
rw_level = (filp->f_flags & O_DIRECT) ? 0 : 1;
ret = ocfs2_rw_lock(inode, rw_level);
if (ret < 0) {
rw_level = -1;
mlog_errno(ret);
goto out;
}
/*
* We sample i_size under a read level meta lock to see if our write
* is extending the file, if it is we back off and get a write level
* meta lock.
*/
meta_level = (filp->f_flags & O_APPEND) ? 1 : 0;
for(;;) {
ret = ocfs2_meta_lock(inode, NULL, NULL, meta_level);
if (ret < 0) {
meta_level = -1;
mlog_errno(ret);
goto out;
}
/* Clear suid / sgid if necessary. We do this here
* instead of later in the write path because
* remove_suid() calls ->setattr without any hint that
* we may have already done our cluster locking. Since
* ocfs2_setattr() *must* take cluster locks to
* proceeed, this will lead us to recursively lock the
* inode. There's also the dinode i_size state which
* can be lost via setattr during extending writes (we
* set inode->i_size at the end of a write. */
if (ocfs2_write_should_remove_suid(inode)) {
if (meta_level == 0) {
ocfs2_meta_unlock(inode, meta_level);
meta_level = 1;
continue;
}
ret = ocfs2_write_remove_suid(inode);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
}
/* work on a copy of ppos until we're sure that we won't have
* to recalculate it due to relocking. */
if (filp->f_flags & O_APPEND) {
saved_pos = i_size_read(inode);
mlog(0, "O_APPEND: inode->i_size=%llu\n", saved_pos);
} else {
saved_pos = iocb->ki_pos;
}
newsize = count + saved_pos;
mlog(0, "pos=%lld newsize=%lld cursize=%lld\n",
(long long) saved_pos, (long long) newsize,
(long long) i_size_read(inode));
/* No need for a higher level metadata lock if we're
* never going past i_size. */
if (newsize <= i_size_read(inode))
break;
if (meta_level == 0) {
ocfs2_meta_unlock(inode, meta_level);
meta_level = 1;
continue;
}
spin_lock(&OCFS2_I(inode)->ip_lock);
clusters = ocfs2_clusters_for_bytes(inode->i_sb, newsize) -
OCFS2_I(inode)->ip_clusters;
spin_unlock(&OCFS2_I(inode)->ip_lock);
mlog(0, "Writing at EOF, may need more allocation: "
"i_size = %lld, newsize = %lld, need %u clusters\n",
(long long) i_size_read(inode), (long long) newsize,
clusters);
/* We only want to continue the rest of this loop if
* our extend will actually require more
* allocation. */
if (!clusters)
break;
ret = ocfs2_extend_allocation(inode, clusters);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
/* Fill any holes which would've been created by this
* write. If we're O_APPEND, this will wind up
* (correctly) being a noop. */
ret = ocfs2_zero_extend(inode, (u64) newsize - count);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
break;
}
/* ok, we're done with i_size and alloc work */
iocb->ki_pos = saved_pos;
ocfs2_meta_unlock(inode, meta_level);
meta_level = -1;
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb);
ret = generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
/* buffered aio wouldn't have proper lock coverage today */
BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
/*
* deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io
* function pointer which is called when o_direct io completes so that
* it can unlock our rw lock. (it's the clustered equivalent of
* i_alloc_sem; protects truncate from racing with pending ios).
* Unfortunately there are error cases which call end_io and others
* that don't. so we don't have to unlock the rw_lock if either an
* async dio is going to do it in the future or an end_io after an
* error has already done it.
*/
if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
rw_level = -1;
have_alloc_sem = 0;
}
out:
if (meta_level != -1)
ocfs2_meta_unlock(inode, meta_level);
if (have_alloc_sem)
up_read(&inode->i_alloc_sem);
if (rw_level != -1)
ocfs2_rw_unlock(inode, rw_level);
mutex_unlock(&inode->i_mutex);
mlog_exit(ret);
return ret;
}
static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
char __user *buf,
size_t count,
loff_t pos)
{
int ret = 0, rw_level = -1, have_alloc_sem = 0;
struct file *filp = iocb->ki_filp;
struct inode *inode = filp->f_dentry->d_inode;
mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", filp, buf,
(unsigned int)count,
filp->f_dentry->d_name.len,
filp->f_dentry->d_name.name);
if (!inode) {
ret = -EINVAL;
mlog_errno(ret);
goto bail;
}
/*
* buffered reads protect themselves in ->readpage(). O_DIRECT reads
* need locks to protect pending reads from racing with truncate.
*/
if (filp->f_flags & O_DIRECT) {
down_read(&inode->i_alloc_sem);
have_alloc_sem = 1;
ret = ocfs2_rw_lock(inode, 0);
if (ret < 0) {
mlog_errno(ret);
goto bail;
}
rw_level = 0;
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb);
}
ret = generic_file_aio_read(iocb, buf, count, iocb->ki_pos);
if (ret == -EINVAL)
mlog(ML_ERROR, "generic_file_aio_read returned -EINVAL\n");
/* buffered aio wouldn't have proper lock coverage today */
BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
/* see ocfs2_file_aio_write */
if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
rw_level = -1;
have_alloc_sem = 0;
}
bail:
if (have_alloc_sem)
up_read(&inode->i_alloc_sem);
if (rw_level != -1)
ocfs2_rw_unlock(inode, rw_level);
mlog_exit(ret);
return ret;
}
struct inode_operations ocfs2_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
};
struct inode_operations ocfs2_special_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
};
struct file_operations ocfs2_fops = {
.read = do_sync_read,
.write = do_sync_write,
.sendfile = generic_file_sendfile,
.mmap = ocfs2_mmap,
.fsync = ocfs2_sync_file,
.release = ocfs2_file_release,
.open = ocfs2_file_open,
.aio_read = ocfs2_file_aio_read,
.aio_write = ocfs2_file_aio_write,
};
struct file_operations ocfs2_dops = {
.read = generic_read_dir,
.readdir = ocfs2_readdir,
.fsync = ocfs2_sync_file,
};
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