kernel_optimize_test/fs/ext4/inline.c
Tao Ma 9c3569b50f ext4: add delalloc support for inline data
For delayed allocation mode, we write to inline data if the file
is small enough. And in case of we write to some offset larger
than the inline size, the 1st page is dirtied, so that
ext4_da_writepages can handle the conversion. When the 1st page
is initialized with blocks, the inline part is removed.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-12-10 14:05:57 -05:00

962 lines
22 KiB
C

/*
* Copyright (c) 2012 Taobao.
* Written by Tao Ma <boyu.mt@taobao.com>
*
* 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 "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))
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_block && 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 += 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;
}
int ext4_has_inline_data(struct inode *inode)
{
return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
EXT4_I(inode)->i_inline_off;
}
/*
* 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_set. That saves
* us one memcpy.
*/
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;
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;
error = ext4_journal_get_write_access(handle, is.iloc.bh);
if (error)
goto out;
if (len > EXT4_MIN_INLINE_DATA_SIZE) {
value = (void *)empty_zero_page;
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_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)
goto out;
error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
value, len);
if (error == -ENODATA)
goto out;
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_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;
}
int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
unsigned int len)
{
int ret, size;
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;
down_write(&EXT4_I(inode)->xattr_sem);
if (ei->i_inline_off)
ret = ext4_update_inline_data(handle, inode, len);
else
ret = ext4_create_inline_data(handle, inode, len);
up_write(&EXT4_I(inode)->xattr_sem);
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;
error = ext4_journal_get_write_access(handle, is.iloc.bh);
if (error)
goto out;
error = ext4_xattr_ibody_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_INCOMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_INCOMPAT_EXTENTS)) {
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_CACHE_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_CACHE_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;
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, 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;
}
down_write(&EXT4_I(inode)->xattr_sem);
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_write);
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);
page_cache_release(page);
ext4_orphan_add(handle, inode);
up_write(&EXT4_I(inode)->xattr_sem);
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;
block_commit_write(page, from, to);
out:
if (page) {
unlock_page(page);
page_cache_release(page);
}
if (sem_held)
up_write(&EXT4_I(inode)->xattr_sem);
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, 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);
page_cache_release(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;
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;
}
down_write(&EXT4_I(inode)->xattr_sem);
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);
up_write(&EXT4_I(inode)->xattr_sem);
brelse(iloc.bh);
out:
return copied;
}
struct buffer_head *
ext4_journalled_write_inline_data(struct inode *inode,
unsigned len,
struct page *page)
{
int ret;
void *kaddr;
struct ext4_iloc iloc;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret) {
ext4_std_error(inode->i_sb, ret);
return NULL;
}
down_write(&EXT4_I(inode)->xattr_sem);
kaddr = kmap_atomic(page);
ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
kunmap_atomic(kaddr);
up_write(&EXT4_I(inode)->xattr_sem);
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) {
ext4_truncate_failed_write(inode);
goto out;
}
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);
page_cache_release(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;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
handle = NULL;
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;
}
if (ret == -ENOSPC) {
ret = ext4_da_convert_inline_data_to_extent(mapping,
inode,
flags,
fsdata);
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;
}
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;
handle = NULL;
brelse(iloc.bh);
return 1;
out_release_page:
up_read(&EXT4_I(inode)->xattr_sem);
unlock_page(page);
page_cache_release(page);
out:
if (handle)
ext4_journal_stop(handle);
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;
copied = ext4_write_inline_data_end(inode, pos, len, copied, page);
/*
* 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);
page_cache_release(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;
}
int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
{
int ret;
down_write(&EXT4_I(inode)->xattr_sem);
ret = ext4_destroy_inline_data_nolock(handle, inode);
up_write(&EXT4_I(inode)->xattr_sem);
return ret;
}