OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
linux/fs/ocfs2/file.c

1867 lines
44 KiB
C
Raw Blame History

/* -*- 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>
#include <linux/sched.h>
#include <linux/splice.h>
#include <linux/mount.h>
#include <linux/writeback.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 "ioctl.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_path.dentry->d_name.len, file->f_path.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_path.dentry->d_name.len,
file->f_path.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_should_update_atime(struct inode *inode,
struct vfsmount *vfsmnt)
{
struct timespec now;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
return 0;
if ((inode->i_flags & S_NOATIME) ||
((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode)))
return 0;
/*
* We can be called with no vfsmnt structure - NFSD will
* sometimes do this.
*
* Note that our action here is different than touch_atime() -
* if we can't tell whether this is a noatime mount, then we
* don't know whether to trust the value of s_atime_quantum.
*/
if (vfsmnt == NULL)
return 0;
if ((vfsmnt->mnt_flags & MNT_NOATIME) ||
((vfsmnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
return 0;
if (vfsmnt->mnt_flags & MNT_RELATIME) {
if ((timespec_compare(&inode->i_atime, &inode->i_mtime) <= 0) ||
(timespec_compare(&inode->i_atime, &inode->i_ctime) <= 0))
return 1;
return 0;
}
now = CURRENT_TIME;
if ((now.tv_sec - inode->i_atime.tv_sec <= osb->s_atime_quantum))
return 0;
else
return 1;
}
int ocfs2_update_inode_atime(struct inode *inode,
struct buffer_head *bh)
{
int ret;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
handle_t *handle;
mlog_entry_void();
handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
if (handle == NULL) {
ret = -ENOMEM;
mlog_errno(ret);
goto out;
}
inode->i_atime = CURRENT_TIME;
ret = ocfs2_mark_inode_dirty(handle, inode, bh);
if (ret < 0)
mlog_errno(ret);
ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
out:
mlog_exit(ret);
return ret;
}
static int ocfs2_set_inode_size(handle_t *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_inode_sector_count(inode);
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);
handle_t *handle = NULL;
handle = ocfs2_start_trans(osb, 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(osb, 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;
handle_t *handle;
struct ocfs2_dinode *di;
mlog_entry_void();
/* TODO: This needs to actually orphan the inode in this
* transaction. */
handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
if (IS_ERR(handle)) {
status = PTR_ERR(handle);
mlog_errno(status);
goto out;
}
status = ocfs2_journal_access(handle, inode, fe_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto out_commit;
}
/*
* Do this before setting i_size.
*/
status = ocfs2_zero_tail_for_truncate(inode, handle, new_i_size);
if (status) {
mlog_errno(status);
goto out_commit;
}
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;
di = (struct ocfs2_dinode *) fe_bh->b_data;
di->i_size = cpu_to_le64(new_i_size);
di->i_ctime = di->i_mtime = cpu_to_le64(inode->i_ctime.tv_sec);
di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
status = ocfs2_journal_dirty(handle, fe_bh);
if (status < 0)
mlog_errno(status);
out_commit:
ocfs2_commit_trans(osb, 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 = %llu, new_i_size = %llu\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno,
(unsigned long long)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 %llu, inode i_size = %lld != di "
"i_size = %llu, i_flags = 0x%x\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno,
i_size_read(inode),
(unsigned long long)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 (%llu) to size (%llu)!\n",
(unsigned long long)le64_to_cpu(fe->i_size),
(unsigned long long)new_i_size);
status = -EINVAL;
mlog_errno(status);
goto bail;
}
mlog(0, "inode %llu, i_size = %llu, new_i_size = %llu\n",
(unsigned long long)le64_to_cpu(fe->i_blkno),
(unsigned long long)le64_to_cpu(fe->i_size),
(unsigned long long)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;
down_write(&OCFS2_I(inode)->ip_alloc_sem);
/* This forces other nodes to sync and drop their pages. Do
* this even if we have a truncate without allocation change -
* ocfs2 cluster sizes can be much greater than page size, so
* we have to truncate them anyway. */
status = ocfs2_data_lock(inode, 1);
if (status < 0) {
up_write(&OCFS2_I(inode)->ip_alloc_sem);
mlog_errno(status);
goto bail;
}
unmap_mapping_range(inode->i_mapping, new_i_size + PAGE_SIZE - 1, 0, 1);
truncate_inode_pages(inode->i_mapping, new_i_size);
/* 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_unlock_data;
}
status = ocfs2_prepare_truncate(osb, inode, di_bh, &tc);
if (status < 0) {
mlog_errno(status);
goto bail_unlock_data;
}
status = ocfs2_commit_truncate(osb, inode, di_bh, tc);
if (status < 0) {
mlog_errno(status);
goto bail_unlock_data;
}
/* TODO: orphan dir cleanup here. */
bail_unlock_data:
ocfs2_data_unlock(inode, 1);
up_write(&OCFS2_I(inode)->ip_alloc_sem);
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 *logical_offset,
u32 clusters_to_add,
struct buffer_head *fe_bh,
handle_t *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 %llu\n",
num_bits, bit_off, (unsigned long long)OCFS2_I(inode)->ip_blkno);
status = ocfs2_insert_extent(osb, handle, inode, fe_bh,
*logical_offset, block, num_bits,
meta_ac);
if (status < 0) {
mlog_errno(status);
goto leave;
}
status = ocfs2_journal_dirty(handle, fe_bh);
if (status < 0) {
mlog_errno(status);
goto leave;
}
clusters_to_add -= num_bits;
*logical_offset += 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;
}
/*
* For a given allocation, determine which allocators will need to be
* accessed, and lock them, reserving the appropriate number of bits.
*
* Called from ocfs2_extend_allocation() for file systems which don't
* support holes, and from ocfs2_write() for file systems which
* understand sparse inodes.
*/
int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
u32 clusters_to_add,
struct ocfs2_alloc_context **data_ac,
struct ocfs2_alloc_context **meta_ac)
{
int ret, num_free_extents;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
*meta_ac = NULL;
*data_ac = NULL;
mlog(0, "extend inode %llu, i_size = %lld, di->i_clusters = %u, "
"clusters_to_add = %u\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno, i_size_read(inode),
le32_to_cpu(di->i_clusters), clusters_to_add);
num_free_extents = ocfs2_num_free_extents(osb, inode, di);
if (num_free_extents < 0) {
ret = num_free_extents;
mlog_errno(ret);
goto out;
}
/*
* Sparse allocation file systems need to be more conservative
* with reserving room for expansion - the actual allocation
* happens while we've got a journal handle open so re-taking
* a cluster lock (because we ran out of room for another
* extent) will violate ordering rules.
*
* Most of the time we'll only be seeing this 1 cluster at a time
* anyway.
*/
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < clusters_to_add)) {
ret = ocfs2_reserve_new_metadata(osb, di, meta_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
}
ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
out:
if (ret) {
if (*meta_ac) {
ocfs2_free_alloc_context(*meta_ac);
*meta_ac = NULL;
}
/*
* We cannot have an error and a non null *data_ac.
*/
}
return ret;
}
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;
u32 prev_clusters, logical_start;
struct buffer_head *bh = NULL;
struct ocfs2_dinode *fe = NULL;
handle_t *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);
/*
* This function only exists for file systems which don't
* support holes.
*/
BUG_ON(ocfs2_sparse_alloc(osb));
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;
}
logical_start = OCFS2_I(inode)->ip_clusters;
restart_all:
BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
/* 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;
status = ocfs2_lock_allocators(inode, fe, clusters_to_add, &data_ac,
&meta_ac);
if (status) {
mlog_errno(status);
goto leave;
}
credits = ocfs2_calc_extend_credits(osb->sb, fe, clusters_to_add);
handle = ocfs2_start_trans(osb, 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,
&logical_start,
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=%llu\n",
le32_to_cpu(fe->i_clusters),
(unsigned long long)le64_to_cpu(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(osb, 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 ->prepare_write() and
* ->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;
handle_t *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_nolock(inode, 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(OCFS2_SB(inode->i_sb), 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;
/*
* Very large extends have the potential to lock up
* the cpu for extended periods of time.
*/
cond_resched();
}
out:
return ret;
}
/*
* A tail_to_skip value > 0 indicates that we're being called from
* ocfs2_file_aio_write(). This has the following implications:
*
* - we don't want to update i_size
* - di_bh will be NULL, which is fine because it's only used in the
* case where we want to update i_size.
* - ocfs2_zero_extend() will then only be filling the hole created
* between i_size and the start of the write.
*/
static int ocfs2_extend_file(struct inode *inode,
struct buffer_head *di_bh,
u64 new_i_size,
size_t tail_to_skip)
{
int ret = 0;
u32 clusters_to_add = 0;
BUG_ON(!tail_to_skip && !di_bh);
/* 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));
if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) {
BUG_ON(tail_to_skip != 0);
goto out_update_size;
}
clusters_to_add = ocfs2_clusters_for_bytes(inode->i_sb, new_i_size) -
OCFS2_I(inode)->ip_clusters;
/*
* protect the pages that ocfs2_zero_extend is going to be
* pulling into the page cache.. we do this before the
* metadata extend so that we don't get into the situation
* where we've extended the metadata but can't get the data
* lock to zero.
*/
ret = ocfs2_data_lock(inode, 1);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
if (clusters_to_add) {
ret = ocfs2_extend_allocation(inode, clusters_to_add);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock;
}
}
/*
* Call this even if we don't add any clusters to the tree. We
* still need to zero the area between the old i_size and the
* new i_size.
*/
ret = ocfs2_zero_extend(inode, (u64)new_i_size - tail_to_skip);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock;
}
out_update_size:
if (!tail_to_skip) {
/* We're being called from ocfs2_setattr() which wants
* us to update i_size */
ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
if (ret < 0)
mlog_errno(ret);
}
out_unlock:
if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
ocfs2_data_unlock(inode, 1);
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;
handle_t *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, &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, 0);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
status = -ENOSPC;
goto bail_unlock;
}
}
handle = ocfs2_start_trans(osb, 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(osb, 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;
}
int ocfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
{
int ret;
mlog_entry_void();
ret = ocfs2_meta_lock(inode, NULL, 0);
if (ret) {
if (ret != -ENOENT)
mlog_errno(ret);
goto out;
}
ret = generic_permission(inode, mask, NULL);
ocfs2_meta_unlock(inode, 0);
out:
mlog_exit(ret);
return ret;
}
static int ocfs2_write_remove_suid(struct inode *inode)
{
int ret;
struct buffer_head *bh = NULL;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
handle_t *handle;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_dinode *di;
mlog_entry("(Inode %llu, mode 0%o)\n",
(unsigned long long)oi->ip_blkno, inode->i_mode);
handle = ocfs2_start_trans(osb, 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(osb, handle);
out:
mlog_exit(ret);
return ret;
}
/*
* Will look for holes and unwritten extents in the range starting at
* pos for count bytes (inclusive).
*/
static int ocfs2_check_range_for_holes(struct inode *inode, loff_t pos,
size_t count)
{
int ret = 0;
unsigned int extent_flags;
u32 cpos, clusters, extent_len, phys_cpos;
struct super_block *sb = inode->i_sb;
cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
while (clusters) {
ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
&extent_flags);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
if (phys_cpos == 0 || (extent_flags & OCFS2_EXT_UNWRITTEN)) {
ret = 1;
break;
}
if (extent_len > clusters)
extent_len = clusters;
clusters -= extent_len;
cpos += extent_len;
}
out:
return ret;
}
static int ocfs2_prepare_inode_for_write(struct dentry *dentry,
loff_t *ppos,
size_t count,
int appending,
int *direct_io)
{
int ret = 0, meta_level = appending;
struct inode *inode = dentry->d_inode;
u32 clusters;
loff_t newsize, saved_pos;
/*
* 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.
*/
for(;;) {
ret = ocfs2_meta_lock(inode, 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 (should_remove_suid(dentry)) {
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_unlock;
}
}
/* work on a copy of ppos until we're sure that we won't have
* to recalculate it due to relocking. */
if (appending) {
saved_pos = i_size_read(inode);
mlog(0, "O_APPEND: inode->i_size=%llu\n", saved_pos);
} else {
saved_pos = *ppos;
}
if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) {
loff_t end = saved_pos + count;
/*
* Skip the O_DIRECT checks if we don't need
* them.
*/
if (!direct_io || !(*direct_io))
break;
/*
* Allowing concurrent direct writes means
* i_size changes wouldn't be synchronized, so
* one node could wind up truncating another
* nodes writes.
*/
if (end > i_size_read(inode)) {
*direct_io = 0;
break;
}
/*
* We don't fill holes during direct io, so
* check for them here. If any are found, the
* caller will have to retake some cluster
* locks and initiate the io as buffered.
*/
ret = ocfs2_check_range_for_holes(inode, saved_pos,
count);
if (ret == 1) {
*direct_io = 0;
ret = 0;
} else if (ret < 0)
mlog_errno(ret);
break;
}
/*
* The rest of this loop is concerned with legacy file
* systems which don't support sparse files.
*/
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_file(inode, NULL, newsize, count);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out_unlock;
}
break;
}
if (appending)
*ppos = saved_pos;
out_unlock:
ocfs2_meta_unlock(inode, meta_level);
out:
return ret;
}
static inline void
ocfs2_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes)
{
const struct iovec *iov = *iovp;
size_t base = *basep;
do {
int copy = min(bytes, iov->iov_len - base);
bytes -= copy;
base += copy;
if (iov->iov_len == base) {
iov++;
base = 0;
}
} while (bytes);
*iovp = iov;
*basep = base;
}
static struct page * ocfs2_get_write_source(char **ret_src_buf,
const struct iovec *cur_iov,
size_t iov_offset)
{
int ret;
char *buf = cur_iov->iov_base + iov_offset;
struct page *src_page = NULL;
unsigned long off;
off = (unsigned long)(buf) & ~PAGE_CACHE_MASK;
if (!segment_eq(get_fs(), KERNEL_DS)) {
/*
* Pull in the user page. We want to do this outside
* of the meta data locks in order to preserve locking
* order in case of page fault.
*/
ret = get_user_pages(current, current->mm,
(unsigned long)buf & PAGE_CACHE_MASK, 1,
0, 0, &src_page, NULL);
if (ret == 1)
*ret_src_buf = kmap(src_page) + off;
else
src_page = ERR_PTR(-EFAULT);
} else {
*ret_src_buf = buf;
}
return src_page;
}
static void ocfs2_put_write_source(struct page *page)
{
if (page) {
kunmap(page);
page_cache_release(page);
}
}
static ssize_t ocfs2_file_buffered_write(struct file *file, loff_t *ppos,
const struct iovec *iov,
unsigned long nr_segs,
size_t count,
ssize_t o_direct_written)
{
int ret = 0;
ssize_t copied, total = 0;
size_t iov_offset = 0, bytes;
loff_t pos;
const struct iovec *cur_iov = iov;
struct page *user_page, *page;
char *buf, *dst;
void *fsdata;
/*
* handle partial DIO write. Adjust cur_iov if needed.
*/
ocfs2_set_next_iovec(&cur_iov, &iov_offset, o_direct_written);
do {
pos = *ppos;
user_page = ocfs2_get_write_source(&buf, cur_iov, iov_offset);
if (IS_ERR(user_page)) {
ret = PTR_ERR(user_page);
goto out;
}
/* Stay within our page boundaries */
bytes = min((PAGE_CACHE_SIZE - ((unsigned long)pos & ~PAGE_CACHE_MASK)),
(PAGE_CACHE_SIZE - ((unsigned long)buf & ~PAGE_CACHE_MASK)));
/* Stay within the vector boundary */
bytes = min_t(size_t, bytes, cur_iov->iov_len - iov_offset);
/* Stay within count */
bytes = min(bytes, count);
page = NULL;
ret = ocfs2_write_begin(file, file->f_mapping, pos, bytes, 0,
&page, &fsdata);
if (ret) {
mlog_errno(ret);
goto out;
}
dst = kmap_atomic(page, KM_USER0);
memcpy(dst + (pos & (PAGE_CACHE_SIZE - 1)), buf, bytes);
kunmap_atomic(dst, KM_USER0);
flush_dcache_page(page);
ocfs2_put_write_source(user_page);
copied = ocfs2_write_end(file, file->f_mapping, pos, bytes,
bytes, page, fsdata);
if (copied < 0) {
mlog_errno(copied);
ret = copied;
goto out;
}
total += copied;
*ppos = pos + copied;
count -= copied;
ocfs2_set_next_iovec(&cur_iov, &iov_offset, copied);
} while(count);
out:
return total ? total : ret;
}
static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
int ret, direct_io, appending, rw_level, have_alloc_sem = 0;
int can_do_direct, sync = 0;
ssize_t written = 0;
size_t ocount; /* original count */
size_t count; /* after file limit checks */
loff_t *ppos = &iocb->ki_pos;
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_path.dentry->d_inode;
mlog_entry("(0x%p, %u, '%.*s')\n", file,
(unsigned int)nr_segs,
file->f_path.dentry->d_name.len,
file->f_path.dentry->d_name.name);
if (iocb->ki_left == 0)
return 0;
ret = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
if (ret)
return ret;
count = ocount;
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
appending = file->f_flags & O_APPEND ? 1 : 0;
direct_io = file->f_flags & O_DIRECT ? 1 : 0;
mutex_lock(&inode->i_mutex);
relock:
/* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */
if (direct_io) {
down_read(&inode->i_alloc_sem);
have_alloc_sem = 1;
}
/* concurrent O_DIRECT writes are allowed */
rw_level = !direct_io;
ret = ocfs2_rw_lock(inode, rw_level);
if (ret < 0) {
mlog_errno(ret);
goto out_sems;
}
can_do_direct = direct_io;
ret = ocfs2_prepare_inode_for_write(file->f_path.dentry, ppos,
iocb->ki_left, appending,
&can_do_direct);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
/*
* We can't complete the direct I/O as requested, fall back to
* buffered I/O.
*/
if (direct_io && !can_do_direct) {
ocfs2_rw_unlock(inode, rw_level);
up_read(&inode->i_alloc_sem);
have_alloc_sem = 0;
rw_level = -1;
direct_io = 0;
sync = 1;
goto relock;
}
if (!sync && ((file->f_flags & O_SYNC) || IS_SYNC(inode)))
sync = 1;
/*
* XXX: Is it ok to execute these checks a second time?
*/
ret = generic_write_checks(file, ppos, &count, S_ISBLK(inode->i_mode));
if (ret)
goto out;
/*
* Set pos so that sync_page_range_nolock() below understands
* where to start from. We might've moved it around via the
* calls above. The range we want to actually sync starts from
* *ppos here.
*
*/
pos = *ppos;
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb, rw_level);
if (direct_io) {
written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos,
ppos, count, ocount);
if (written < 0) {
ret = written;
goto out_dio;
}
} else {
written = ocfs2_file_buffered_write(file, ppos, iov, nr_segs,
count, written);
if (written < 0) {
ret = written;
if (ret != -EFAULT || ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
}
out_dio:
/* buffered aio wouldn't have proper lock coverage today */
BUG_ON(ret == -EIOCBQUEUED && !(file->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 (rw_level != -1)
ocfs2_rw_unlock(inode, rw_level);
out_sems:
if (have_alloc_sem)
up_read(&inode->i_alloc_sem);
if (written > 0 && sync) {
ssize_t err;
err = sync_page_range_nolock(inode, file->f_mapping, pos, count);
if (err < 0)
written = err;
}
mutex_unlock(&inode->i_mutex);
mlog_exit(ret);
return written ? written : ret;
}
static int ocfs2_splice_write_actor(struct pipe_inode_info *pipe,
struct pipe_buffer *buf,
struct splice_desc *sd)
{
int ret, count;
ssize_t copied = 0;
struct file *file = sd->u.file;
unsigned int offset;
struct page *page = NULL;
void *fsdata;
char *src, *dst;
ret = buf->ops->confirm(pipe, buf);
if (ret)
goto out;
offset = sd->pos & ~PAGE_CACHE_MASK;
count = sd->len;
if (count + offset > PAGE_CACHE_SIZE)
count = PAGE_CACHE_SIZE - offset;
ret = ocfs2_write_begin(file, file->f_mapping, sd->pos, count, 0,
&page, &fsdata);
if (ret) {
mlog_errno(ret);
goto out;
}
src = buf->ops->map(pipe, buf, 1);
dst = kmap_atomic(page, KM_USER1);
memcpy(dst + offset, src + buf->offset, count);
kunmap_atomic(page, KM_USER1);
buf->ops->unmap(pipe, buf, src);
copied = ocfs2_write_end(file, file->f_mapping, sd->pos, count, count,
page, fsdata);
if (copied < 0) {
mlog_errno(copied);
ret = copied;
goto out;
}
out:
return copied ? copied : ret;
}
static ssize_t __ocfs2_file_splice_write(struct pipe_inode_info *pipe,
struct file *out,
loff_t *ppos,
size_t len,
unsigned int flags)
{
int ret, err;
struct address_space *mapping = out->f_mapping;
struct inode *inode = mapping->host;
struct splice_desc sd = {
.total_len = len,
.flags = flags,
.pos = *ppos,
.u.file = out,
};
ret = __splice_from_pipe(pipe, &sd, ocfs2_splice_write_actor);
if (ret > 0) {
*ppos += ret;
if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
err = generic_osync_inode(inode, mapping,
OSYNC_METADATA|OSYNC_DATA);
if (err)
ret = err;
}
}
return ret;
}
static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe,
struct file *out,
loff_t *ppos,
size_t len,
unsigned int flags)
{
int ret;
struct inode *inode = out->f_path.dentry->d_inode;
mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", out, pipe,
(unsigned int)len,
out->f_path.dentry->d_name.len,
out->f_path.dentry->d_name.name);
inode_double_lock(inode, pipe->inode);
ret = ocfs2_rw_lock(inode, 1);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
ret = ocfs2_prepare_inode_for_write(out->f_path.dentry, ppos, len, 0,
NULL);
if (ret < 0) {
mlog_errno(ret);
goto out_unlock;
}
/* ok, we're done with i_size and alloc work */
ret = __ocfs2_file_splice_write(pipe, out, ppos, len, flags);
out_unlock:
ocfs2_rw_unlock(inode, 1);
out:
inode_double_unlock(inode, pipe->inode);
mlog_exit(ret);
return ret;
}
static ssize_t ocfs2_file_splice_read(struct file *in,
loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len,
unsigned int flags)
{
int ret = 0;
struct inode *inode = in->f_path.dentry->d_inode;
mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", in, pipe,
(unsigned int)len,
in->f_path.dentry->d_name.len,
in->f_path.dentry->d_name.name);
/*
* See the comment in ocfs2_file_aio_read()
*/
ret = ocfs2_meta_lock(inode, NULL, 0);
if (ret < 0) {
mlog_errno(ret);
goto bail;
}
ocfs2_meta_unlock(inode, 0);
ret = generic_file_splice_read(in, ppos, pipe, len, flags);
bail:
mlog_exit(ret);
return ret;
}
static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
int ret = 0, rw_level = -1, have_alloc_sem = 0, lock_level = 0;
struct file *filp = iocb->ki_filp;
struct inode *inode = filp->f_path.dentry->d_inode;
mlog_entry("(0x%p, %u, '%.*s')\n", filp,
(unsigned int)nr_segs,
filp->f_path.dentry->d_name.len,
filp->f_path.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, rw_level);
}
/*
* We're fine letting folks race truncates and extending
* writes with read across the cluster, just like they can
* locally. Hence no rw_lock during read.
*
* Take and drop the meta data lock to update inode fields
* like i_size. This allows the checks down below
* generic_file_aio_read() a chance of actually working.
*/
ret = ocfs2_meta_lock_atime(inode, filp->f_vfsmnt, &lock_level);
if (ret < 0) {
mlog_errno(ret);
goto bail;
}
ocfs2_meta_unlock(inode, lock_level);
ret = generic_file_aio_read(iocb, iov, nr_segs, 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;
}
const struct inode_operations ocfs2_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
.permission = ocfs2_permission,
};
const struct inode_operations ocfs2_special_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
.permission = ocfs2_permission,
};
const struct file_operations ocfs2_fops = {
.read = do_sync_read,
.write = do_sync_write,
.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,
.ioctl = ocfs2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ocfs2_compat_ioctl,
#endif
.splice_read = ocfs2_file_splice_read,
.splice_write = ocfs2_file_splice_write,
};
const struct file_operations ocfs2_dops = {
.read = generic_read_dir,
.readdir = ocfs2_readdir,
.fsync = ocfs2_sync_file,
.ioctl = ocfs2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ocfs2_compat_ioctl,
#endif
};
Reference in New Issue View Git Blame Copy Permalink