Commit 65d165d9 authored by Tao Ma's avatar Tao Ma Committed by Theodore Ts'o
Browse files

ext4: let ext4_readdir handle inline data



For "." and "..", we just call filldir by ourselves
instead of iterating the real dir entry.
Signed-off-by: default avatarTao Ma <boyu.mt@taobao.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 3c47d541
......@@ -27,23 +27,11 @@
#include <linux/slab.h>
#include <linux/rbtree.h>
#include "ext4.h"
static unsigned char ext4_filetype_table[] = {
DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
};
#include "xattr.h"
static int ext4_dx_readdir(struct file *filp,
void *dirent, filldir_t filldir);
static unsigned char get_dtype(struct super_block *sb, int filetype)
{
if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
(filetype >= EXT4_FT_MAX))
return DT_UNKNOWN;
return (ext4_filetype_table[filetype]);
}
/**
* Check if the given dir-inode refers to an htree-indexed directory
* (or a directory which chould potentially get coverted to use htree
......@@ -68,6 +56,9 @@ static int is_dx_dir(struct inode *inode)
* Return 0 if the directory entry is OK, and 1 if there is a problem
*
* Note: this is the opposite of what ext2 and ext3 historically returned...
*
* bh passed here can be an inode block or a dir data block, depending
* on the inode inline data flag.
*/
int __ext4_check_dir_entry(const char *function, unsigned int line,
struct inode *dir, struct file *filp,
......@@ -124,6 +115,14 @@ static int ext4_readdir(struct file *filp,
int ret = 0;
int dir_has_error = 0;
if (ext4_has_inline_data(inode)) {
int has_inline_data = 1;
ret = ext4_read_inline_dir(filp, dirent, filldir,
&has_inline_data);
if (has_inline_data)
return ret;
}
if (is_dx_dir(inode)) {
err = ext4_dx_readdir(filp, dirent, filldir);
if (err != ERR_BAD_DX_DIR) {
......
......@@ -1989,6 +1989,18 @@ static inline void ext4_update_dx_flag(struct inode *inode)
EXT4_FEATURE_COMPAT_DIR_INDEX))
ext4_clear_inode_flag(inode, EXT4_INODE_INDEX);
}
static unsigned char ext4_filetype_table[] = {
DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
};
static inline unsigned char get_dtype(struct super_block *sb, int filetype)
{
if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
(filetype >= EXT4_FT_MAX))
return DT_UNKNOWN;
return ext4_filetype_table[filetype];
}
/* fsync.c */
extern int ext4_sync_file(struct file *, loff_t, loff_t, int);
......
......@@ -1288,6 +1288,142 @@ int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
return ret;
}
int ext4_read_inline_dir(struct file *filp,
void *dirent, filldir_t filldir,
int *has_inline_data)
{
int error = 0;
unsigned int offset, parent_ino;
int i, stored;
struct ext4_dir_entry_2 *de;
struct super_block *sb;
struct inode *inode = filp->f_path.dentry->d_inode;
int ret, inline_size = 0;
struct ext4_iloc iloc;
void *dir_buf = NULL;
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
up_read(&EXT4_I(inode)->xattr_sem);
*has_inline_data = 0;
goto out;
}
inline_size = ext4_get_inline_size(inode);
dir_buf = kmalloc(inline_size, GFP_NOFS);
if (!dir_buf) {
ret = -ENOMEM;
up_read(&EXT4_I(inode)->xattr_sem);
goto out;
}
ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
up_read(&EXT4_I(inode)->xattr_sem);
if (ret < 0)
goto out;
sb = inode->i_sb;
stored = 0;
parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
while (!error && !stored && filp->f_pos < inode->i_size) {
revalidate:
/*
* If the version has changed since the last call to
* readdir(2), then we might be pointing to an invalid
* dirent right now. Scan from the start of the inline
* dir to make sure.
*/
if (filp->f_version != inode->i_version) {
for (i = 0;
i < inode->i_size && i < offset;) {
if (!i) {
/* skip "." and ".." if needed. */
i += EXT4_INLINE_DOTDOT_SIZE;
continue;
}
de = (struct ext4_dir_entry_2 *)
(dir_buf + i);
/* It's too expensive to do a full
* dirent test each time round this
* loop, but we do have to test at
* least that it is non-zero. A
* failure will be detected in the
* dirent test below. */
if (ext4_rec_len_from_disk(de->rec_len,
inline_size) < EXT4_DIR_REC_LEN(1))
break;
i += ext4_rec_len_from_disk(de->rec_len,
inline_size);
}
offset = i;
filp->f_pos = offset;
filp->f_version = inode->i_version;
}
while (!error && filp->f_pos < inode->i_size) {
if (filp->f_pos == 0) {
error = filldir(dirent, ".", 1, 0, inode->i_ino,
DT_DIR);
if (error)
break;
stored++;
error = filldir(dirent, "..", 2, 0, parent_ino,
DT_DIR);
if (error)
break;
stored++;
filp->f_pos = offset = EXT4_INLINE_DOTDOT_SIZE;
continue;
}
de = (struct ext4_dir_entry_2 *)(dir_buf + offset);
if (ext4_check_dir_entry(inode, filp, de,
iloc.bh, dir_buf,
inline_size, offset)) {
ret = stored;
goto out;
}
offset += ext4_rec_len_from_disk(de->rec_len,
inline_size);
if (le32_to_cpu(de->inode)) {
/* We might block in the next section
* if the data destination is
* currently swapped out. So, use a
* version stamp to detect whether or
* not the directory has been modified
* during the copy operation.
*/
u64 version = filp->f_version;
error = filldir(dirent, de->name,
de->name_len,
filp->f_pos,
le32_to_cpu(de->inode),
get_dtype(sb, de->file_type));
if (error)
break;
if (version != filp->f_version)
goto revalidate;
stored++;
}
filp->f_pos += ext4_rec_len_from_disk(de->rec_len,
inline_size);
}
offset = 0;
}
out:
kfree(dir_buf);
brelse(iloc.bh);
return ret;
}
/*
* Try to create the inline data for the new dir.
* If it succeeds, return 0, otherwise return the error.
......
......@@ -168,6 +168,9 @@ extern int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
extern int ext4_try_create_inline_dir(handle_t *handle,
struct inode *parent,
struct inode *inode);
extern int ext4_read_inline_dir(struct file *filp,
void *dirent, filldir_t filldir,
int *has_inline_data);
# else /* CONFIG_EXT4_FS_XATTR */
static inline int
......@@ -346,6 +349,12 @@ static inline int ext4_try_create_inline_dir(handle_t *handle,
{
return 0;
}
static inline int ext4_read_inline_dir(struct file *filp,
void *dirent, filldir_t filldir,
int *has_inline_data)
{
return 0;
}
# endif /* CONFIG_EXT4_FS_XATTR */
#ifdef CONFIG_EXT4_FS_SECURITY
......
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