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/*
* linux/fs/ext3/namei.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/namei.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* Big-endian to little-endian byte-swapping/bitmaps by
* David S. Miller (davem@caip.rutgers.edu), 1995
* Directory entry file type support and forward compatibility hooks
* for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
*/
#include <linux/fs.h>
#include <linux/jbd.h>
#include <linux/sched.h>
#include <linux/ext3_fs.h>
#include <linux/ext3_jbd.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/locks.h>
#include <linux/quotaops.h>
/*
* define how far ahead to read directories while searching them.
*/
#define NAMEI_RA_CHUNKS 2
#define NAMEI_RA_BLOCKS 4
#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
/*
* NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure.
*
* `len <= EXT3_NAME_LEN' is guaranteed by caller.
* `de != NULL' is guaranteed by caller.
*/
static inline int ext3_match (int len, const char * const name,
struct ext3_dir_entry_2 * de)
{
if (len != de->name_len)
return 0;
if (!de->inode)
return 0;
return !memcmp(name, de->name, len);
}
/*
* Returns 0 if not found, -1 on failure, and 1 on success
*/
static int inline search_dirblock(struct buffer_head * bh,
struct inode *dir,
struct dentry *dentry,
unsigned long offset,
struct ext3_dir_entry_2 ** res_dir)
{
struct ext3_dir_entry_2 * de;
char * dlimit;
int de_len;
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
de = (struct ext3_dir_entry_2 *) bh->b_data;
dlimit = bh->b_data + dir->i_sb->s_blocksize;
while ((char *) de < dlimit) {
/* this code is executed quadratically often */
/* do minimal checking `by hand' */
if ((char *) de + namelen <= dlimit &&
ext3_match (namelen, name, de)) {
/* found a match - just to be sure, do a full check */
if (!ext3_check_dir_entry("ext3_find_entry",
dir, de, bh, offset))
return -1;
*res_dir = de;
return 1;
}
/* prevent looping on a bad block */
de_len = le16_to_cpu(de->rec_len);
if (de_len <= 0)
return -1;
offset += de_len;
de = (struct ext3_dir_entry_2 *) ((char *) de + de_len);
}
return 0;
}
/*
* ext3_find_entry()
*
* finds an entry in the specified directory with the wanted name. It
* returns the cache buffer in which the entry was found, and the entry
* itself (as a parameter - res_dir). It does NOT read the inode of the
* entry - you'll have to do that yourself if you want to.
*
* The returned buffer_head has ->b_count elevated. The caller is expected
* to brelse() it when appropriate.
*/
static struct buffer_head * ext3_find_entry (struct dentry *dentry,
struct ext3_dir_entry_2 ** res_dir)
{
struct super_block * sb;
struct buffer_head * bh_use[NAMEI_RA_SIZE];
struct buffer_head * bh, *ret = NULL;
unsigned long start, block, b;
int ra_max = 0; /* Number of bh's in the readahead
buffer, bh_use[] */
int ra_ptr = 0; /* Current index into readahead
buffer */
int num = 0;
int nblocks, i, err;
struct inode *dir = dentry->d_parent->d_inode;
*res_dir = NULL;
sb = dir->i_sb;
nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
start = dir->u.ext3_i.i_dir_start_lookup;
if (start >= nblocks)
start = 0;
block = start;
restart:
do {
/*
* We deal with the read-ahead logic here.
*/
if (ra_ptr >= ra_max) {
/* Refill the readahead buffer */
ra_ptr = 0;
b = block;
for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
/*
* Terminate if we reach the end of the
* directory and must wrap, or if our
* search has finished at this block.
*/
if (b >= nblocks || (num && block == start)) {
bh_use[ra_max] = NULL;
break;
}
num++;
bh = ext3_getblk(NULL, dir, b++, 0, &err);
bh_use[ra_max] = bh;
if (bh)
ll_rw_block(READ, 1, &bh);
}
}
if ((bh = bh_use[ra_ptr++]) == NULL)
goto next;
wait_on_buffer(bh);
if (!buffer_uptodate(bh)) {
/* read error, skip block & hope for the best */
brelse(bh);
goto next;
}
i = search_dirblock(bh, dir, dentry,
block << EXT3_BLOCK_SIZE_BITS(sb), res_dir);
if (i == 1) {
dir->u.ext3_i.i_dir_start_lookup = block;
ret = bh;
goto cleanup_and_exit;
} else {
brelse(bh);
if (i < 0)
goto cleanup_and_exit;
}
next:
if (++block >= nblocks)
block = 0;
} while (block != start);
/*
* If the directory has grown while we were searching, then
* search the last part of the directory before giving up.
*/
block = nblocks;
nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
if (block < nblocks) {
start = 0;
goto restart;
}
cleanup_and_exit:
/* Clean up the read-ahead blocks */
for (; ra_ptr < ra_max; ra_ptr++)
brelse (bh_use[ra_ptr]);
return ret;
}
static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry)
{
struct inode * inode;
struct ext3_dir_entry_2 * de;
struct buffer_head * bh;
if (dentry->d_name.len > EXT3_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
bh = ext3_find_entry(dentry, &de);
inode = NULL;
if (bh) {
unsigned long ino = le32_to_cpu(de->inode);
brelse (bh);
inode = iget(dir->i_sb, ino);
if (!inode)
return ERR_PTR(-EACCES);
}
d_add(dentry, inode);
return NULL;
}
#define S_SHIFT 12
static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = {
[S_IFREG >> S_SHIFT] EXT3_FT_REG_FILE,
[S_IFDIR >> S_SHIFT] EXT3_FT_DIR,
[S_IFCHR >> S_SHIFT] EXT3_FT_CHRDEV,
[S_IFBLK >> S_SHIFT] EXT3_FT_BLKDEV,
[S_IFIFO >> S_SHIFT] EXT3_FT_FIFO,
[S_IFSOCK >> S_SHIFT] EXT3_FT_SOCK,
[S_IFLNK >> S_SHIFT] EXT3_FT_SYMLINK,
};
static inline void ext3_set_de_type(struct super_block *sb,
struct ext3_dir_entry_2 *de,
umode_t mode) {
if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE))
de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
}
/*
* ext3_add_entry()
*
* adds a file entry to the specified directory, using the same
* semantics as ext3_find_entry(). It returns NULL if it failed.
*
* NOTE!! The inode part of 'de' is left at 0 - which means you
* may not sleep between calling this and putting something into
* the entry, as someone else might have used it while you slept.
*/
/*
* AKPM: the journalling code here looks wrong on the error paths
*/
static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
struct inode *inode)
{
struct inode *dir = dentry->d_parent->d_inode;
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
unsigned long offset;
unsigned short rec_len;
struct buffer_head * bh;
struct ext3_dir_entry_2 * de, * de1;
struct super_block * sb;
int retval;
sb = dir->i_sb;
if (!namelen)
return -EINVAL;
bh = ext3_bread (handle, dir, 0, 0, &retval);
if (!bh)
return retval;
rec_len = EXT3_DIR_REC_LEN(namelen);
offset = 0;
de = (struct ext3_dir_entry_2 *) bh->b_data;
while (1) {
if ((char *)de >= sb->s_blocksize + bh->b_data) {
brelse (bh);
bh = NULL;
bh = ext3_bread (handle, dir,
offset >> EXT3_BLOCK_SIZE_BITS(sb), 1, &retval);
if (!bh)
return retval;
if (dir->i_size <= offset) {
if (dir->i_size == 0) {
brelse(bh);
return -ENOENT;
}
ext3_debug ("creating next block\n");
BUFFER_TRACE(bh, "get_write_access");
ext3_journal_get_write_access(handle, bh);
de = (struct ext3_dir_entry_2 *) bh->b_data;
de->inode = 0;
de->rec_len = le16_to_cpu(sb->s_blocksize);
dir->u.ext3_i.i_disksize =
dir->i_size = offset + sb->s_blocksize;
dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, dir);
} else {
ext3_debug ("skipping to next block\n");
de = (struct ext3_dir_entry_2 *) bh->b_data;
}
}
if (!ext3_check_dir_entry ("ext3_add_entry", dir, de, bh,
offset)) {
brelse (bh);
return -ENOENT;
}
if (ext3_match (namelen, name, de)) {
brelse (bh);
return -EEXIST;
}
if ((le32_to_cpu(de->inode) == 0 &&
le16_to_cpu(de->rec_len) >= rec_len) ||
(le16_to_cpu(de->rec_len) >=
EXT3_DIR_REC_LEN(de->name_len) + rec_len)) {
BUFFER_TRACE(bh, "get_write_access");
ext3_journal_get_write_access(handle, bh);
/* By now the buffer is marked for journaling */
offset += le16_to_cpu(de->rec_len);
if (le32_to_cpu(de->inode)) {
de1 = (struct ext3_dir_entry_2 *) ((char *) de +
EXT3_DIR_REC_LEN(de->name_len));
de1->rec_len =
cpu_to_le16(le16_to_cpu(de->rec_len) -
EXT3_DIR_REC_LEN(de->name_len));
de->rec_len = cpu_to_le16(
EXT3_DIR_REC_LEN(de->name_len));
de = de1;
}
de->file_type = EXT3_FT_UNKNOWN;
if (inode) {
de->inode = cpu_to_le32(inode->i_ino);
ext3_set_de_type(dir->i_sb, de, inode->i_mode);
} else
de->inode = 0;
de->name_len = namelen;
memcpy (de->name, name, namelen);
/*
* XXX shouldn't update any times until successful
* completion of syscall, but too many callers depend
* on this.
*
* XXX similarly, too many callers depend on
* ext3_new_inode() setting the times, but error
* recovery deletes the inode, so the worst that can
* happen is that the times are slightly out of date
* and/or different from the directory change time.
*/
dir->i_mtime = dir->i_ctime = CURRENT_TIME;
dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, dir);
dir->i_version = ++event;
BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
ext3_journal_dirty_metadata(handle, bh);
brelse(bh);
return 0;
}
offset += le16_to_cpu(de->rec_len);
de = (struct ext3_dir_entry_2 *)
((char *) de + le16_to_cpu(de->rec_len));
}
brelse (bh);
return -ENOSPC;
}
/*
* ext3_delete_entry deletes a directory entry by merging it with the
* previous entry
*/
static int ext3_delete_entry (handle_t *handle,
struct inode * dir,
struct ext3_dir_entry_2 * de_del,
struct buffer_head * bh)
{
struct ext3_dir_entry_2 * de, * pde;
int i;
i = 0;
pde = NULL;
de = (struct ext3_dir_entry_2 *) bh->b_data;
while (i < bh->b_size) {
if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i))
return -EIO;
if (de == de_del) {
BUFFER_TRACE(bh, "get_write_access");
ext3_journal_get_write_access(handle, bh);
if (pde)
pde->rec_len =
cpu_to_le16(le16_to_cpu(pde->rec_len) +
le16_to_cpu(de->rec_len));
else
de->inode = 0;
dir->i_version = ++event;
BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
ext3_journal_dirty_metadata(handle, bh);
return 0;
}
i += le16_to_cpu(de->rec_len);
pde = de;
de = (struct ext3_dir_entry_2 *)
((char *) de + le16_to_cpu(de->rec_len));
}
return -ENOENT;
}
/*
* ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we
* do not perform it in these functions. We perform it at the call site,
* if it is needed.
*/
static inline void ext3_inc_count(handle_t *handle, struct inode *inode)
{
inode->i_nlink++;
}
static inline void ext3_dec_count(handle_t *handle, struct inode *inode)
{
inode->i_nlink--;
}
static int ext3_add_nondir(handle_t *handle,
struct dentry *dentry, struct inode *inode)
{
int err = ext3_add_entry(handle, dentry, inode);
if (!err) {
d_instantiate(dentry, inode);
return 0;
}
ext3_dec_count(handle, inode);
iput(inode);
return err;
}
/*
* By the time this is called, we already have created
* the directory cache entry for the new file, but it
* is so far negative - it has no inode.
*
* If the create succeeds, we fill in the inode information
* with d_instantiate().
*/
static int ext3_create (struct inode * dir, struct dentry * dentry, int mode)
{
handle_t *handle;
struct inode * inode;
int err;
handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS + 3);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
inode = ext3_new_inode (handle, dir, mode);
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
inode->i_op = &ext3_file_inode_operations;
inode->i_fop = &ext3_file_operations;
inode->i_mapping->a_ops = &ext3_aops;
ext3_mark_inode_dirty(handle, inode);
err = ext3_add_nondir(handle, dentry, inode);
}
ext3_journal_stop(handle, dir);
return err;
}
static int ext3_mknod (struct inode * dir, struct dentry *dentry,
int mode, int rdev)
{
handle_t *handle;
struct inode *inode;
int err;
handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS + 3);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
inode = ext3_new_inode (handle, dir, mode);
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
init_special_inode(inode, mode, rdev);
ext3_mark_inode_dirty(handle, inode);
err = ext3_add_nondir(handle, dentry, inode);
}
ext3_journal_stop(handle, dir);
return err;
}
static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode)
{
handle_t *handle;
struct inode * inode;
struct buffer_head * dir_block;
struct ext3_dir_entry_2 * de;
int err;
if (dir->i_nlink >= EXT3_LINK_MAX)
return -EMLINK;
handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS + 3);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
inode = ext3_new_inode (handle, dir, S_IFDIR);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_stop;
inode->i_op = &ext3_dir_inode_operations;
inode->i_fop = &ext3_dir_operations;
inode->i_size = inode->u.ext3_i.i_disksize = inode->i_sb->s_blocksize;
inode->i_blocks = 0;
dir_block = ext3_bread (handle, inode, 0, 1, &err);
if (!dir_block) {
inode->i_nlink--; /* is this nlink == 0? */
ext3_mark_inode_dirty(handle, inode);
iput (inode);
goto out_stop;
}
BUFFER_TRACE(dir_block, "get_write_access");
ext3_journal_get_write_access(handle, dir_block);
de = (struct ext3_dir_entry_2 *) dir_block->b_data;
de->inode = cpu_to_le32(inode->i_ino);
de->name_len = 1;
de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len));
strcpy (de->name, ".");
ext3_set_de_type(dir->i_sb, de, S_IFDIR);
de = (struct ext3_dir_entry_2 *)
((char *) de + le16_to_cpu(de->rec_len));
de->inode = cpu_to_le32(dir->i_ino);
de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1));
de->name_len = 2;
strcpy (de->name, "..");
ext3_set_de_type(dir->i_sb, de, S_IFDIR);
inode->i_nlink = 2;
BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata");
ext3_journal_dirty_metadata(handle, dir_block);
brelse (dir_block);
inode->i_mode = S_IFDIR | mode;
if (dir->i_mode & S_ISGID)
inode->i_mode |= S_ISGID;
ext3_mark_inode_dirty(handle, inode);
err = ext3_add_entry (handle, dentry, inode);
if (err)
goto out_no_entry;
dir->i_nlink++;
dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, dir);
d_instantiate(dentry, inode);
out_stop:
ext3_journal_stop(handle, dir);
return err;
out_no_entry:
inode->i_nlink = 0;
ext3_mark_inode_dirty(handle, inode);
iput (inode);
goto out_stop;
}
/*
* routine to check that the specified directory is empty (for rmdir)
*/
static int empty_dir (struct inode * inode)
{
unsigned long offset;
struct buffer_head * bh;
struct ext3_dir_entry_2 * de, * de1;
struct super_block * sb;
int err;
sb = inode->i_sb;
if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) ||
!(bh = ext3_bread (NULL, inode, 0, 0, &err))) {
ext3_warning (inode->i_sb, "empty_dir",
"bad directory (dir #%lu) - no data block",
inode->i_ino);
return 1;
}
de = (struct ext3_dir_entry_2 *) bh->b_data;
de1 = (struct ext3_dir_entry_2 *)
((char *) de + le16_to_cpu(de->rec_len));
if (le32_to_cpu(de->inode) != inode->i_ino ||
!le32_to_cpu(de1->inode) ||
strcmp (".", de->name) ||
strcmp ("..", de1->name)) {
ext3_warning (inode->i_sb, "empty_dir",
"bad directory (dir #%lu) - no `.' or `..'",
inode->i_ino);
brelse (bh);
return 1;
}
offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
de = (struct ext3_dir_entry_2 *)
((char *) de1 + le16_to_cpu(de1->rec_len));
while (offset < inode->i_size ) {
if (!bh ||
(void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
brelse (bh);
bh = ext3_bread (NULL, inode,
offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err);
if (!bh) {
#if 0
ext3_error (sb, "empty_dir",
"directory #%lu contains a hole at offset %lu",
inode->i_ino, offset);
#endif
offset += sb->s_blocksize;
continue;
}
de = (struct ext3_dir_entry_2 *) bh->b_data;
}
if (!ext3_check_dir_entry ("empty_dir", inode, de, bh,
offset)) {
brelse (bh);
return 1;
}
if (le32_to_cpu(de->inode)) {
brelse (bh);
return 0;
}
offset += le16_to_cpu(de->rec_len);
de = (struct ext3_dir_entry_2 *)
((char *) de + le16_to_cpu(de->rec_len));
}
brelse (bh);
return 1;
}
/* ext3_orphan_add() links an unlinked or truncated inode into a list of
* such inodes, starting at the superblock, in case we crash before the
* file is closed/deleted, or in case the inode truncate spans multiple
* transactions and the last transaction is not recovered after a crash.
*
* At filesystem recovery time, we walk this list deleting unlinked
* inodes and truncating linked inodes in ext3_orphan_cleanup().
*/
int ext3_orphan_add(handle_t *handle, struct inode *inode)
{
struct super_block *sb = inode->i_sb;
struct ext3_iloc iloc;
int err = 0, rc;
lock_super(sb);
if (!list_empty(&inode->u.ext3_i.i_orphan))
goto out_unlock;
/* Orphan handling is only valid for files with data blocks
* being truncated, or files being unlinked. */
/* @@@ FIXME: Observation from aviro:
* I think I can trigger J_ASSERT in ext3_orphan_add(). We block
* here (on lock_super()), so race with ext3_link() which might bump
* ->i_nlink. For, say it, character device. Not a regular file,
* not a directory, not a symlink and ->i_nlink > 0.
*/
J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
BUFFER_TRACE(sb->u.ext3_sb.s_sbh, "get_write_access");
err = ext3_journal_get_write_access(handle, sb->u.ext3_sb.s_sbh);
if (err)
goto out_unlock;
err = ext3_reserve_inode_write(handle, inode, &iloc);
if (err)
goto out_unlock;
/* Insert this inode at the head of the on-disk orphan list... */
NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan);
EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
err = ext3_journal_dirty_metadata(handle, sb->u.ext3_sb.s_sbh);
rc = ext3_mark_iloc_dirty(handle, inode, &iloc);
if (!err)
err = rc;
/* Only add to the head of the in-memory list if all the
* previous operations succeeded. If the orphan_add is going to
* fail (possibly taking the journal offline), we can't risk
* leaving the inode on the orphan list: stray orphan-list
* entries can cause panics at unmount time.
*
* This is safe: on error we're going to ignore the orphan list
* anyway on the next recovery. */
if (!err)
list_add(&inode->u.ext3_i.i_orphan, &EXT3_SB(sb)->s_orphan);
jbd_debug(4, "superblock will point to %ld\n", inode->i_ino);
jbd_debug(4, "orphan inode %ld will point to %d\n",
inode->i_ino, NEXT_ORPHAN(inode));
out_unlock:
unlock_super(sb);
ext3_std_error(inode->i_sb, err);
return err;
}
/*
* ext3_orphan_del() removes an unlinked or truncated inode from the list
* of such inodes stored on disk, because it is finally being cleaned up.
*/
int ext3_orphan_del(handle_t *handle, struct inode *inode)
{
struct list_head *prev;
struct ext3_sb_info *sbi;
ino_t ino_next;
struct ext3_iloc iloc;
int err = 0;
lock_super(inode->i_sb);
if (list_empty(&inode->u.ext3_i.i_orphan)) {
unlock_super(inode->i_sb);
return 0;
}
ino_next = NEXT_ORPHAN(inode);
prev = inode->u.ext3_i.i_orphan.prev;
sbi = EXT3_SB(inode->i_sb);
jbd_debug(4, "remove inode %ld from orphan list\n", inode->i_ino);
list_del(&inode->u.ext3_i.i_orphan);
INIT_LIST_HEAD(&inode->u.ext3_i.i_orphan);
/* If we're on an error path, we may not have a valid
* transaction handle with which to update the orphan list on
* disk, but we still need to remove the inode from the linked
* list in memory. */
if (!handle)
goto out;
err = ext3_reserve_inode_write(handle, inode, &iloc);
if (err)
goto out_err;
if (prev == &sbi->s_orphan) {
jbd_debug(4, "superblock will point to %ld\n", ino_next);
BUFFER_TRACE(sbi->s_sbh, "get_write_access");
err = ext3_journal_get_write_access(handle, sbi->s_sbh);
if (err)
goto out_brelse;
sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
} else {
struct ext3_iloc iloc2;
struct inode *i_prev =
list_entry(prev, struct inode, u.ext3_i.i_orphan);
jbd_debug(4, "orphan inode %ld will point to %ld\n",
i_prev->i_ino, ino_next);
err = ext3_reserve_inode_write(handle, i_prev, &iloc2);
if (err)
goto out_brelse;
NEXT_ORPHAN(i_prev) = ino_next;
err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2);
}
if (err)
goto out_brelse;
NEXT_ORPHAN(inode) = 0;
err = ext3_mark_iloc_dirty(handle, inode, &iloc);
if (err)
goto out_brelse;
out_err:
ext3_std_error(inode->i_sb, err);
out:
unlock_super(inode->i_sb);
return err;
out_brelse:
brelse(iloc.bh);
goto out_err;
}
static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
{
int retval;
struct inode * inode;
struct buffer_head * bh;
struct ext3_dir_entry_2 * de;
handle_t *handle;
handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS);
if (IS_ERR(handle))
return PTR_ERR(handle);
retval = -ENOENT;
bh = ext3_find_entry (dentry, &de);
if (!bh)
goto end_rmdir;
if (IS_SYNC(dir))
handle->h_sync = 1;
inode = dentry->d_inode;
DQUOT_INIT(inode);
retval = -EIO;
if (le32_to_cpu(de->inode) != inode->i_ino)
goto end_rmdir;
retval = -ENOTEMPTY;
if (!empty_dir (inode))
goto end_rmdir;
retval = ext3_delete_entry(handle, dir, de, bh);
if (retval)
goto end_rmdir;
if (inode->i_nlink != 2)
ext3_warning (inode->i_sb, "ext3_rmdir",
"empty directory has nlink!=2 (%d)",
inode->i_nlink);
inode->i_version = ++event;
inode->i_nlink = 0;
/* There's no need to set i_disksize: the fact that i_nlink is
* zero will ensure that the right thing happens during any
* recovery. */
inode->i_size = 0;
ext3_orphan_add(handle, inode);
ext3_mark_inode_dirty(handle, inode);
dir->i_nlink--;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, dir);
end_rmdir:
ext3_journal_stop(handle, dir);
brelse (bh);
return retval;
}
static int ext3_unlink(struct inode * dir, struct dentry *dentry)
{
int retval;
struct inode * inode;
struct buffer_head * bh;
struct ext3_dir_entry_2 * de;
handle_t *handle;
handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
retval = -ENOENT;
bh = ext3_find_entry (dentry, &de);
if (!bh)
goto end_unlink;
inode = dentry->d_inode;
DQUOT_INIT(inode);
retval = -EIO;
if (le32_to_cpu(de->inode) != inode->i_ino)
goto end_unlink;
if (!inode->i_nlink) {
ext3_warning (inode->i_sb, "ext3_unlink",
"Deleting nonexistent file (%lu), %d",
inode->i_ino, inode->i_nlink);
inode->i_nlink = 1;
}
retval = ext3_delete_entry(handle, dir, de, bh);
if (retval)
goto end_unlink;
dir->i_ctime = dir->i_mtime = CURRENT_TIME;
dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, dir);
inode->i_nlink--;
if (!inode->i_nlink)
ext3_orphan_add(handle, inode);
ext3_mark_inode_dirty(handle, inode);
inode->i_ctime = dir->i_ctime;
retval = 0;
end_unlink:
ext3_journal_stop(handle, dir);
brelse (bh);
return retval;
}
static int ext3_symlink (struct inode * dir,
struct dentry *dentry, const char * symname)
{
handle_t *handle;
struct inode * inode;
int l, err;
l = strlen(symname)+1;
if (l > dir->i_sb->s_blocksize)
return -ENAMETOOLONG;
handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS + 5);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_stop;
if (l > sizeof (inode->u.ext3_i.i_data)) {
inode->i_op = &page_symlink_inode_operations;
inode->i_mapping->a_ops = &ext3_aops;
/*
* block_symlink() calls back into ext3_prepare/commit_write.
* We have a transaction open. All is sweetness. It also sets
* i_size in generic_commit_write().
*/
err = block_symlink(inode, symname, l);
if (err)
goto out_no_entry;
} else {
inode->i_op = &ext3_fast_symlink_inode_operations;
memcpy((char*)&inode->u.ext3_i.i_data,symname,l);
inode->i_size = l-1;
}
inode->u.ext3_i.i_disksize = inode->i_size;
ext3_mark_inode_dirty(handle, inode);
err = ext3_add_nondir(handle, dentry, inode);
out_stop:
ext3_journal_stop(handle, dir);
return err;
out_no_entry:
ext3_dec_count(handle, inode);
ext3_mark_inode_dirty(handle, inode);
iput (inode);
goto out_stop;
}
static int ext3_link (struct dentry * old_dentry,
struct inode * dir, struct dentry *dentry)
{
handle_t *handle;
struct inode *inode = old_dentry->d_inode;
int err;
if (S_ISDIR(inode->i_mode))
return -EPERM;
if (inode->i_nlink >= EXT3_LINK_MAX)
return -EMLINK;
handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(dir))
handle->h_sync = 1;
inode->i_ctime = CURRENT_TIME;
ext3_inc_count(handle, inode);
atomic_inc(&inode->i_count);
ext3_mark_inode_dirty(handle, inode);
err = ext3_add_nondir(handle, dentry, inode);
ext3_journal_stop(handle, dir);
return err;
}
#define PARENT_INO(buffer) \
((struct ext3_dir_entry_2 *) ((char *) buffer + \
le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode
/*
* Anybody can rename anything with this: the permission checks are left to the
* higher-level routines.
*/
static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
struct inode * new_dir,struct dentry *new_dentry)
{
handle_t *handle;
struct inode * old_inode, * new_inode;
struct buffer_head * old_bh, * new_bh, * dir_bh;
struct ext3_dir_entry_2 * old_de, * new_de;
int retval;
old_bh = new_bh = dir_bh = NULL;
handle = ext3_journal_start(old_dir, 2 * EXT3_DATA_TRANS_BLOCKS + 2);
if (IS_ERR(handle))
return PTR_ERR(handle);
if (IS_SYNC(old_dir) || IS_SYNC(new_dir))
handle->h_sync = 1;
old_bh = ext3_find_entry (old_dentry, &old_de);
/*
* Check for inode number is _not_ due to possible IO errors.
* We might rmdir the source, keep it as pwd of some process
* and merrily kill the link to whatever was created under the
* same name. Goodbye sticky bit ;-<
*/
old_inode = old_dentry->d_inode;
retval = -ENOENT;
if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
goto end_rename;
new_inode = new_dentry->d_inode;
new_bh = ext3_find_entry (new_dentry, &new_de);
if (new_bh) {
if (!new_inode) {
brelse (new_bh);
new_bh = NULL;
} else {
DQUOT_INIT(new_inode);
}
}
if (S_ISDIR(old_inode->i_mode)) {
if (new_inode) {
retval = -ENOTEMPTY;
if (!empty_dir (new_inode))
goto end_rename;
}
retval = -EIO;
dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval);
if (!dir_bh)
goto end_rename;
if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
goto end_rename;
retval = -EMLINK;
if (!new_inode && new_dir!=old_dir &&
new_dir->i_nlink >= EXT3_LINK_MAX)
goto end_rename;
}
if (!new_bh) {
retval = ext3_add_entry (handle, new_dentry, old_inode);
if (retval)
goto end_rename;
} else {
BUFFER_TRACE(new_bh, "get write access");
BUFFER_TRACE(new_bh, "get_write_access");
ext3_journal_get_write_access(handle, new_bh);
new_de->inode = le32_to_cpu(old_inode->i_ino);
if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
EXT3_FEATURE_INCOMPAT_FILETYPE))
new_de->file_type = old_de->file_type;
new_dir->i_version = ++event;
BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata");
ext3_journal_dirty_metadata(handle, new_bh);
brelse(new_bh);
new_bh = NULL;
}
/*
* Like most other Unix systems, set the ctime for inodes on a
* rename.
*/
old_inode->i_ctime = CURRENT_TIME;
ext3_mark_inode_dirty(handle, old_inode);
/*
* ok, that's it
*/
ext3_delete_entry(handle, old_dir, old_de, old_bh);
if (new_inode) {
new_inode->i_nlink--;
new_inode->i_ctime = CURRENT_TIME;
}
old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
old_dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
if (dir_bh) {
BUFFER_TRACE(dir_bh, "get_write_access");
ext3_journal_get_write_access(handle, dir_bh);
PARENT_INO(dir_bh->b_data) = le32_to_cpu(new_dir->i_ino);
BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
ext3_journal_dirty_metadata(handle, dir_bh);
old_dir->i_nlink--;
if (new_inode) {
new_inode->i_nlink--;
} else {
new_dir->i_nlink++;
new_dir->u.ext3_i.i_flags &= ~EXT3_INDEX_FL;
ext3_mark_inode_dirty(handle, new_dir);
}
}
ext3_mark_inode_dirty(handle, old_dir);
if (new_inode) {
ext3_mark_inode_dirty(handle, new_inode);
if (!new_inode->i_nlink)
ext3_orphan_add(handle, new_inode);
}
retval = 0;
end_rename:
brelse (dir_bh);
brelse (old_bh);
brelse (new_bh);
ext3_journal_stop(handle, old_dir);
return retval;
}
/*
* directories can handle most operations...
*/
struct inode_operations ext3_dir_inode_operations = {
create: ext3_create, /* BKL held */
lookup: ext3_lookup, /* BKL held */
link: ext3_link, /* BKL held */
unlink: ext3_unlink, /* BKL held */
symlink: ext3_symlink, /* BKL held */
mkdir: ext3_mkdir, /* BKL held */
rmdir: ext3_rmdir, /* BKL held */
mknod: ext3_mknod, /* BKL held */
rename: ext3_rename, /* BKL held */
};
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