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inline.c
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/*
* Copyright (c) 2012 Taobao.
* Written by Tao Ma <[email protected]>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2.1 of the GNU Lesser General Public License
* as published by the Free Software Foundation.
*
* 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.
*/
#include <linux/iomap.h>
#include <linux/fiemap.h>
#include "ext4_jbd2.h"
#include "ext4.h"
#include "xattr.h"
#include "truncate.h"
#define EXT4_XATTR_SYSTEM_DATA "data"
#define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__le32) * EXT4_N_BLOCKS))
#define EXT4_INLINE_DOTDOT_OFFSET 2
#define EXT4_INLINE_DOTDOT_SIZE 4
static int ext4_get_inline_size(struct inode *inode)
{
if (EXT4_I(inode)->i_inline_off)
return EXT4_I(inode)->i_inline_size;
return 0;
}
static int get_max_inline_xattr_value_size(struct inode *inode,
struct ext4_iloc *iloc)
{
struct ext4_xattr_ibody_header *header;
struct ext4_xattr_entry *entry;
struct ext4_inode *raw_inode;
int free, min_offs;
min_offs = EXT4_SB(inode->i_sb)->s_inode_size -
EXT4_GOOD_OLD_INODE_SIZE -
EXT4_I(inode)->i_extra_isize -
sizeof(struct ext4_xattr_ibody_header);
/*
* We need to subtract another sizeof(__u32) since an in-inode xattr
* needs an empty 4 bytes to indicate the gap between the xattr entry
* and the name/value pair.
*/
if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
return EXT4_XATTR_SIZE(min_offs -
EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA)) -
EXT4_XATTR_ROUND - sizeof(__u32));
raw_inode = ext4_raw_inode(iloc);
header = IHDR(inode, raw_inode);
entry = IFIRST(header);
/* Compute min_offs. */
for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
if (!entry->e_value_inum && entry->e_value_size) {
size_t offs = le16_to_cpu(entry->e_value_offs);
if (offs < min_offs)
min_offs = offs;
}
}
free = min_offs -
((void *)entry - (void *)IFIRST(header)) - sizeof(__u32);
if (EXT4_I(inode)->i_inline_off) {
entry = (struct ext4_xattr_entry *)
((void *)raw_inode + EXT4_I(inode)->i_inline_off);
free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
goto out;
}
free -= EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA));
if (free > EXT4_XATTR_ROUND)
free = EXT4_XATTR_SIZE(free - EXT4_XATTR_ROUND);
else
free = 0;
out:
return free;
}
/*
* Get the maximum size we now can store in an inode.
* If we can't find the space for a xattr entry, don't use the space
* of the extents since we have no space to indicate the inline data.
*/
int ext4_get_max_inline_size(struct inode *inode)
{
int error, max_inline_size;
struct ext4_iloc iloc;
if (EXT4_I(inode)->i_extra_isize == 0)
return 0;
error = ext4_get_inode_loc(inode, &iloc);
if (error) {
ext4_error_inode(inode, __func__, __LINE__, 0,
"can't get inode location %lu",
inode->i_ino);
return 0;
}
down_read(&EXT4_I(inode)->xattr_sem);
max_inline_size = get_max_inline_xattr_value_size(inode, &iloc);
up_read(&EXT4_I(inode)->xattr_sem);
brelse(iloc.bh);
if (!max_inline_size)
return 0;
return max_inline_size + EXT4_MIN_INLINE_DATA_SIZE;
}
/*
* this function does not take xattr_sem, which is OK because it is
* currently only used in a code path coming form ext4_iget, before
* the new inode has been unlocked
*/
int ext4_find_inline_data_nolock(struct inode *inode)
{
struct ext4_xattr_ibody_find is = {
.s = { .not_found = -ENODATA, },
};
struct ext4_xattr_info i = {
.name_index = EXT4_XATTR_INDEX_SYSTEM,
.name = EXT4_XATTR_SYSTEM_DATA,
};
int error;
if (EXT4_I(inode)->i_extra_isize == 0)
return 0;
error = ext4_get_inode_loc(inode, &is.iloc);
if (error)
return error;
error = ext4_xattr_ibody_find(inode, &i, &is);
if (error)
goto out;
if (!is.s.not_found) {
EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
(void *)ext4_raw_inode(&is.iloc));
EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
le32_to_cpu(is.s.here->e_value_size);
ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
}
out:
brelse(is.iloc.bh);
return error;
}
static int ext4_read_inline_data(struct inode *inode, void *buffer,
unsigned int len,
struct ext4_iloc *iloc)
{
struct ext4_xattr_entry *entry;
struct ext4_xattr_ibody_header *header;
int cp_len = 0;
struct ext4_inode *raw_inode;
if (!len)
return 0;
BUG_ON(len > EXT4_I(inode)->i_inline_size);
cp_len = len < EXT4_MIN_INLINE_DATA_SIZE ?
len : EXT4_MIN_INLINE_DATA_SIZE;
raw_inode = ext4_raw_inode(iloc);
memcpy(buffer, (void *)(raw_inode->i_block), cp_len);
len -= cp_len;
buffer += cp_len;
if (!len)
goto out;
header = IHDR(inode, raw_inode);
entry = (struct ext4_xattr_entry *)((void *)raw_inode +
EXT4_I(inode)->i_inline_off);
len = min_t(unsigned int, len,
(unsigned int)le32_to_cpu(entry->e_value_size));
memcpy(buffer,
(void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs), len);
cp_len += len;
out:
return cp_len;
}
/*
* write the buffer to the inline inode.
* If 'create' is set, we don't need to do the extra copy in the xattr
* value since it is already handled by ext4_xattr_ibody_inline_set.
* That saves us one memcpy.
*/
static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
void *buffer, loff_t pos, unsigned int len)
{
struct ext4_xattr_entry *entry;
struct ext4_xattr_ibody_header *header;
struct ext4_inode *raw_inode;
int cp_len = 0;
if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
return;
BUG_ON(!EXT4_I(inode)->i_inline_off);
BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
raw_inode = ext4_raw_inode(iloc);
buffer += pos;
if (pos < EXT4_MIN_INLINE_DATA_SIZE) {
cp_len = pos + len > EXT4_MIN_INLINE_DATA_SIZE ?
EXT4_MIN_INLINE_DATA_SIZE - pos : len;
memcpy((void *)raw_inode->i_block + pos, buffer, cp_len);
len -= cp_len;
buffer += cp_len;
pos += cp_len;
}
if (!len)
return;
pos -= EXT4_MIN_INLINE_DATA_SIZE;
header = IHDR(inode, raw_inode);
entry = (struct ext4_xattr_entry *)((void *)raw_inode +
EXT4_I(inode)->i_inline_off);
memcpy((void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs) + pos,
buffer, len);
}
static int ext4_create_inline_data(handle_t *handle,
struct inode *inode, unsigned len)
{
int error;
void *value = NULL;
struct ext4_xattr_ibody_find is = {
.s = { .not_found = -ENODATA, },
};
struct ext4_xattr_info i = {
.name_index = EXT4_XATTR_INDEX_SYSTEM,
.name = EXT4_XATTR_SYSTEM_DATA,
};
error = ext4_get_inode_loc(inode, &is.iloc);
if (error)
return error;
BUFFER_TRACE(is.iloc.bh, "get_write_access");
error = ext4_journal_get_write_access(handle, is.iloc.bh);
if (error)
goto out;
if (len > EXT4_MIN_INLINE_DATA_SIZE) {
value = EXT4_ZERO_XATTR_VALUE;
len -= EXT4_MIN_INLINE_DATA_SIZE;
} else {
value = "";
len = 0;
}
/* Insert the the xttr entry. */
i.value = value;
i.value_len = len;
error = ext4_xattr_ibody_find(inode, &i, &is);
if (error)
goto out;
BUG_ON(!is.s.not_found);
error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
if (error) {
if (error == -ENOSPC)
ext4_clear_inode_state(inode,
EXT4_STATE_MAY_INLINE_DATA);
goto out;
}
memset((void *)ext4_raw_inode(&is.iloc)->i_block,
0, EXT4_MIN_INLINE_DATA_SIZE);
EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
(void *)ext4_raw_inode(&is.iloc));
EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
get_bh(is.iloc.bh);
error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
out:
brelse(is.iloc.bh);
return error;
}
static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
unsigned int len)
{
int error;
void *value = NULL;
struct ext4_xattr_ibody_find is = {
.s = { .not_found = -ENODATA, },
};
struct ext4_xattr_info i = {
.name_index = EXT4_XATTR_INDEX_SYSTEM,
.name = EXT4_XATTR_SYSTEM_DATA,
};
/* If the old space is ok, write the data directly. */
if (len <= EXT4_I(inode)->i_inline_size)
return 0;
error = ext4_get_inode_loc(inode, &is.iloc);
if (error)
return error;
error = ext4_xattr_ibody_find(inode, &i, &is);
if (error)
goto out;
BUG_ON(is.s.not_found);
len -= EXT4_MIN_INLINE_DATA_SIZE;
value = kzalloc(len, GFP_NOFS);
if (!value) {
error = -ENOMEM;
goto out;
}
error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
value, len);
if (error == -ENODATA)
goto out;
BUFFER_TRACE(is.iloc.bh, "get_write_access");
error = ext4_journal_get_write_access(handle, is.iloc.bh);
if (error)
goto out;
/* Update the xttr entry. */
i.value = value;
i.value_len = len;
error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
if (error)
goto out;
EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
(void *)ext4_raw_inode(&is.iloc));
EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
le32_to_cpu(is.s.here->e_value_size);
ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
get_bh(is.iloc.bh);
error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
out:
kfree(value);
brelse(is.iloc.bh);
return error;
}
static int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
unsigned int len)
{
int ret, size, no_expand;
struct ext4_inode_info *ei = EXT4_I(inode);
if (!ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
return -ENOSPC;
size = ext4_get_max_inline_size(inode);
if (size < len)
return -ENOSPC;
ext4_write_lock_xattr(inode, &no_expand);
if (ei->i_inline_off)
ret = ext4_update_inline_data(handle, inode, len);
else
ret = ext4_create_inline_data(handle, inode, len);
ext4_write_unlock_xattr(inode, &no_expand);
return ret;
}
static int ext4_destroy_inline_data_nolock(handle_t *handle,
struct inode *inode)
{
struct ext4_inode_info *ei = EXT4_I(inode);
struct ext4_xattr_ibody_find is = {
.s = { .not_found = 0, },
};
struct ext4_xattr_info i = {
.name_index = EXT4_XATTR_INDEX_SYSTEM,
.name = EXT4_XATTR_SYSTEM_DATA,
.value = NULL,
.value_len = 0,
};
int error;
if (!ei->i_inline_off)
return 0;
error = ext4_get_inode_loc(inode, &is.iloc);
if (error)
return error;
error = ext4_xattr_ibody_find(inode, &i, &is);
if (error)
goto out;
BUFFER_TRACE(is.iloc.bh, "get_write_access");
error = ext4_journal_get_write_access(handle, is.iloc.bh);
if (error)
goto out;
error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
if (error)
goto out;
memset((void *)ext4_raw_inode(&is.iloc)->i_block,
0, EXT4_MIN_INLINE_DATA_SIZE);
if (ext4_has_feature_extents(inode->i_sb)) {
if (S_ISDIR(inode->i_mode) ||
S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)) {
ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
ext4_ext_tree_init(handle, inode);
}
}
ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
get_bh(is.iloc.bh);
error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
EXT4_I(inode)->i_inline_off = 0;
EXT4_I(inode)->i_inline_size = 0;
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
out:
brelse(is.iloc.bh);
if (error == -ENODATA)
error = 0;
return error;
}
static int ext4_read_inline_page(struct inode *inode, struct page *page)
{
void *kaddr;
int ret = 0;
size_t len;
struct ext4_iloc iloc;
BUG_ON(!PageLocked(page));
BUG_ON(!ext4_has_inline_data(inode));
BUG_ON(page->index);
if (!EXT4_I(inode)->i_inline_off) {
ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
inode->i_ino);
goto out;
}
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
goto out;
len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
kaddr = kmap_atomic(page);
ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
flush_dcache_page(page);
kunmap_atomic(kaddr);
zero_user_segment(page, len, PAGE_SIZE);
SetPageUptodate(page);
brelse(iloc.bh);
out:
return ret;
}
int ext4_readpage_inline(struct inode *inode, struct page *page)
{
int ret = 0;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
up_read(&EXT4_I(inode)->xattr_sem);
return -EAGAIN;
}
/*
* Current inline data can only exist in the 1st page,
* So for all the other pages, just set them uptodate.
*/
if (!page->index)
ret = ext4_read_inline_page(inode, page);
else if (!PageUptodate(page)) {
zero_user_segment(page, 0, PAGE_SIZE);
SetPageUptodate(page);
}
up_read(&EXT4_I(inode)->xattr_sem);
unlock_page(page);
return ret >= 0 ? 0 : ret;
}
static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
struct inode *inode,
unsigned flags)
{
int ret, needed_blocks, no_expand;
handle_t *handle = NULL;
int retries = 0, sem_held = 0;
struct page *page = NULL;
unsigned from, to;
struct ext4_iloc iloc;
if (!ext4_has_inline_data(inode)) {
/*
* clear the flag so that no new write
* will trap here again.
*/
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
return 0;
}
needed_blocks = ext4_writepage_trans_blocks(inode);
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
retry:
handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
handle = NULL;
goto out;
}
/* We cannot recurse into the filesystem as the transaction is already
* started */
flags |= AOP_FLAG_NOFS;
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page) {
ret = -ENOMEM;
goto out;
}
ext4_write_lock_xattr(inode, &no_expand);
sem_held = 1;
/* If some one has already done this for us, just exit. */
if (!ext4_has_inline_data(inode)) {
ret = 0;
goto out;
}
from = 0;
to = ext4_get_inline_size(inode);
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out;
}
ret = ext4_destroy_inline_data_nolock(handle, inode);
if (ret)
goto out;
if (ext4_should_dioread_nolock(inode)) {
ret = __block_write_begin(page, from, to,
ext4_get_block_unwritten);
} else
ret = __block_write_begin(page, from, to, ext4_get_block);
if (!ret && ext4_should_journal_data(inode)) {
ret = ext4_walk_page_buffers(handle, page_buffers(page),
from, to, NULL,
do_journal_get_write_access);
}
if (ret) {
unlock_page(page);
put_page(page);
page = NULL;
ext4_orphan_add(handle, inode);
ext4_write_unlock_xattr(inode, &no_expand);
sem_held = 0;
ext4_journal_stop(handle);
handle = NULL;
ext4_truncate_failed_write(inode);
/*
* If truncate failed early the inode might
* still be on the orphan list; we need to
* make sure the inode is removed from the
* orphan list in that case.
*/
if (inode->i_nlink)
ext4_orphan_del(NULL, inode);
}
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
goto retry;
if (page)
block_commit_write(page, from, to);
out:
if (page) {
unlock_page(page);
put_page(page);
}
if (sem_held)
ext4_write_unlock_xattr(inode, &no_expand);
if (handle)
ext4_journal_stop(handle);
brelse(iloc.bh);
return ret;
}
/*
* Try to write data in the inode.
* If the inode has inline data, check whether the new write can be
* in the inode also. If not, create the page the handle, move the data
* to the page make it update and let the later codes create extent for it.
*/
int ext4_try_to_write_inline_data(struct address_space *mapping,
struct inode *inode,
loff_t pos, unsigned len,
unsigned flags,
struct page **pagep)
{
int ret;
handle_t *handle;
struct page *page;
struct ext4_iloc iloc;
if (pos + len > ext4_get_max_inline_size(inode))
goto convert;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
/*
* The possible write could happen in the inode,
* so try to reserve the space in inode first.
*/
handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
handle = NULL;
goto out;
}
ret = ext4_prepare_inline_data(handle, inode, pos + len);
if (ret && ret != -ENOSPC)
goto out;
/* We don't have space in inline inode, so convert it to extent. */
if (ret == -ENOSPC) {
ext4_journal_stop(handle);
brelse(iloc.bh);
goto convert;
}
flags |= AOP_FLAG_NOFS;
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page) {
ret = -ENOMEM;
goto out;
}
*pagep = page;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
ret = 0;
unlock_page(page);
put_page(page);
goto out_up_read;
}
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out_up_read;
}
ret = 1;
handle = NULL;
out_up_read:
up_read(&EXT4_I(inode)->xattr_sem);
out:
if (handle)
ext4_journal_stop(handle);
brelse(iloc.bh);
return ret;
convert:
return ext4_convert_inline_data_to_extent(mapping,
inode, flags);
}
int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
unsigned copied, struct page *page)
{
int ret, no_expand;
void *kaddr;
struct ext4_iloc iloc;
if (unlikely(copied < len)) {
if (!PageUptodate(page)) {
copied = 0;
goto out;
}
}
ret = ext4_get_inode_loc(inode, &iloc);
if (ret) {
ext4_std_error(inode->i_sb, ret);
copied = 0;
goto out;
}
ext4_write_lock_xattr(inode, &no_expand);
BUG_ON(!ext4_has_inline_data(inode));
kaddr = kmap_atomic(page);
ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
kunmap_atomic(kaddr);
SetPageUptodate(page);
/* clear page dirty so that writepages wouldn't work for us. */
ClearPageDirty(page);
ext4_write_unlock_xattr(inode, &no_expand);
brelse(iloc.bh);
out:
return copied;
}
struct buffer_head *
ext4_journalled_write_inline_data(struct inode *inode,
unsigned len,
struct page *page)
{
int ret, no_expand;
void *kaddr;
struct ext4_iloc iloc;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret) {
ext4_std_error(inode->i_sb, ret);
return NULL;
}
ext4_write_lock_xattr(inode, &no_expand);
kaddr = kmap_atomic(page);
ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
kunmap_atomic(kaddr);
ext4_write_unlock_xattr(inode, &no_expand);
return iloc.bh;
}
/*
* Try to make the page cache and handle ready for the inline data case.
* We can call this function in 2 cases:
* 1. The inode is created and the first write exceeds inline size. We can
* clear the inode state safely.
* 2. The inode has inline data, then we need to read the data, make it
* update and dirty so that ext4_da_writepages can handle it. We don't
* need to start the journal since the file's metatdata isn't changed now.
*/
static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
struct inode *inode,
unsigned flags,
void **fsdata)
{
int ret = 0, inline_size;
struct page *page;
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page)
return -ENOMEM;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
goto out;
}
inline_size = ext4_get_inline_size(inode);
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out;
}
ret = __block_write_begin(page, 0, inline_size,
ext4_da_get_block_prep);
if (ret) {
up_read(&EXT4_I(inode)->xattr_sem);
unlock_page(page);
put_page(page);
ext4_truncate_failed_write(inode);
return ret;
}
SetPageDirty(page);
SetPageUptodate(page);
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
*fsdata = (void *)CONVERT_INLINE_DATA;
out:
up_read(&EXT4_I(inode)->xattr_sem);
if (page) {
unlock_page(page);
put_page(page);
}
return ret;
}
/*
* Prepare the write for the inline data.
* If the the data can be written into the inode, we just read
* the page and make it uptodate, and start the journal.
* Otherwise read the page, makes it dirty so that it can be
* handle in writepages(the i_disksize update is left to the
* normal ext4_da_write_end).
*/
int ext4_da_write_inline_data_begin(struct address_space *mapping,
struct inode *inode,
loff_t pos, unsigned len,
unsigned flags,
struct page **pagep,
void **fsdata)
{
int ret, inline_size;
handle_t *handle;
struct page *page;
struct ext4_iloc iloc;
int retries;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
retry_journal:
handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
goto out;
}
inline_size = ext4_get_max_inline_size(inode);
ret = -ENOSPC;
if (inline_size >= pos + len) {
ret = ext4_prepare_inline_data(handle, inode, pos + len);
if (ret && ret != -ENOSPC)
goto out_journal;
}
/*
* We cannot recurse into the filesystem as the transaction
* is already started.
*/
flags |= AOP_FLAG_NOFS;
if (ret == -ENOSPC) {
ret = ext4_da_convert_inline_data_to_extent(mapping,
inode,
flags,
fsdata);
ext4_journal_stop(handle);
if (ret == -ENOSPC &&
ext4_should_retry_alloc(inode->i_sb, &retries))
goto retry_journal;
goto out;
}
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page) {
ret = -ENOMEM;
goto out_journal;
}
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
ret = 0;
goto out_release_page;
}
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out_release_page;
}
up_read(&EXT4_I(inode)->xattr_sem);
*pagep = page;
brelse(iloc.bh);
return 1;
out_release_page:
up_read(&EXT4_I(inode)->xattr_sem);
unlock_page(page);
put_page(page);
out_journal:
ext4_journal_stop(handle);
out:
brelse(iloc.bh);
return ret;
}
int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
unsigned len, unsigned copied,
struct page *page)
{
int i_size_changed = 0;
int ret;
ret = ext4_write_inline_data_end(inode, pos, len, copied, page);
if (ret < 0) {
unlock_page(page);
put_page(page);
return ret;
}
copied = ret;
/*
* No need to use i_size_read() here, the i_size
* cannot change under us because we hold i_mutex.
*
* But it's important to update i_size while still holding page lock:
* page writeout could otherwise come in and zero beyond i_size.
*/
if (pos+copied > inode->i_size) {
i_size_write(inode, pos+copied);
i_size_changed = 1;
}
unlock_page(page);
put_page(page);
/*
* Don't mark the inode dirty under page lock. First, it unnecessarily
* makes the holding time of page lock longer. Second, it forces lock
* ordering of page lock and transaction start for journaling
* filesystems.
*/
if (i_size_changed)
mark_inode_dirty(inode);
return copied;
}
#ifdef INLINE_DIR_DEBUG
void ext4_show_inline_dir(struct inode *dir, struct buffer_head *bh,
void *inline_start, int inline_size)
{
int offset;
unsigned short de_len;
struct ext4_dir_entry_2 *de = inline_start;
void *dlimit = inline_start + inline_size;
trace_printk("inode %lu\n", dir->i_ino);
offset = 0;
while ((void *)de < dlimit) {
de_len = ext4_rec_len_from_disk(de->rec_len, inline_size);
trace_printk("de: off %u rlen %u name %.*s nlen %u ino %u\n",
offset, de_len, de->name_len, de->name,
de->name_len, le32_to_cpu(de->inode));
if (ext4_check_dir_entry(dir, NULL, de, bh,
inline_start, inline_size, offset))
BUG();
offset += de_len;
de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
}
}
#else