From 734711abac46c8fee4d70cc9876ebc6d9edb4971 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 24 Aug 2008 07:26:48 -0400 Subject: [PATCH] get rid of on-stack fake dentry in ext3_get_parent() Better pass parent and qstr to ext3_find_entry() explicitly than use such kludges, especially since the stack footprint is nasty enough and we have every chance to be deep in call chain. Signed-off-by: Al Viro --- fs/ext3/namei.c | 70 +++++++++++++++++++++++++++------------------------------ 1 file changed, 33 insertions(+), 37 deletions(-) (limited to 'fs/ext3') diff --git a/fs/ext3/namei.c b/fs/ext3/namei.c index 880b54400ac0..3e5edc92aa0b 100644 --- a/fs/ext3/namei.c +++ b/fs/ext3/namei.c @@ -159,7 +159,7 @@ static void dx_set_count (struct dx_entry *entries, unsigned value); static void dx_set_limit (struct dx_entry *entries, unsigned value); static unsigned dx_root_limit (struct inode *dir, unsigned infosize); static unsigned dx_node_limit (struct inode *dir); -static struct dx_frame *dx_probe(struct dentry *dentry, +static struct dx_frame *dx_probe(struct qstr *entry, struct inode *dir, struct dx_hash_info *hinfo, struct dx_frame *frame, @@ -176,8 +176,9 @@ static int ext3_htree_next_block(struct inode *dir, __u32 hash, struct dx_frame *frame, struct dx_frame *frames, __u32 *start_hash); -static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, - struct ext3_dir_entry_2 **res_dir, int *err); +static struct buffer_head * ext3_dx_find_entry(struct inode *dir, + struct qstr *entry, struct ext3_dir_entry_2 **res_dir, + int *err); static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, struct inode *inode); @@ -342,7 +343,7 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, * back to userspace. */ static struct dx_frame * -dx_probe(struct dentry *dentry, struct inode *dir, +dx_probe(struct qstr *entry, struct inode *dir, struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) { unsigned count, indirect; @@ -353,8 +354,6 @@ dx_probe(struct dentry *dentry, struct inode *dir, u32 hash; frame->bh = NULL; - if (dentry) - dir = dentry->d_parent->d_inode; if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) goto fail; root = (struct dx_root *) bh->b_data; @@ -370,8 +369,8 @@ dx_probe(struct dentry *dentry, struct inode *dir, } hinfo->hash_version = root->info.hash_version; hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; - if (dentry) - ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo); + if (entry) + ext3fs_dirhash(entry->name, entry->len, hinfo); hash = hinfo->hash; if (root->info.unused_flags & 1) { @@ -803,15 +802,15 @@ static inline int ext3_match (int len, const char * const name, */ static inline int search_dirblock(struct buffer_head * bh, struct inode *dir, - struct dentry *dentry, + struct qstr *child, 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; + const char *name = child->name; + int namelen = child->len; de = (struct ext3_dir_entry_2 *) bh->b_data; dlimit = bh->b_data + dir->i_sb->s_blocksize; @@ -850,8 +849,9 @@ static inline int search_dirblock(struct buffer_head * bh, * 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) +static struct buffer_head *ext3_find_entry(struct inode *dir, + struct qstr *entry, + struct ext3_dir_entry_2 **res_dir) { struct super_block * sb; struct buffer_head * bh_use[NAMEI_RA_SIZE]; @@ -863,16 +863,15 @@ static struct buffer_head * ext3_find_entry (struct dentry *dentry, buffer */ int num = 0; int nblocks, i, err; - struct inode *dir = dentry->d_parent->d_inode; int namelen; *res_dir = NULL; sb = dir->i_sb; - namelen = dentry->d_name.len; + namelen = entry->len; if (namelen > EXT3_NAME_LEN) return NULL; if (is_dx(dir)) { - bh = ext3_dx_find_entry(dentry, res_dir, &err); + bh = ext3_dx_find_entry(dir, entry, res_dir, &err); /* * On success, or if the error was file not found, * return. Otherwise, fall back to doing a search the @@ -923,7 +922,7 @@ restart: brelse(bh); goto next; } - i = search_dirblock(bh, dir, dentry, + i = search_dirblock(bh, dir, entry, block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); if (i == 1) { EXT3_I(dir)->i_dir_start_lookup = block; @@ -957,8 +956,9 @@ cleanup_and_exit: return ret; } -static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, - struct ext3_dir_entry_2 **res_dir, int *err) +static struct buffer_head * ext3_dx_find_entry(struct inode *dir, + struct qstr *entry, struct ext3_dir_entry_2 **res_dir, + int *err) { struct super_block * sb; struct dx_hash_info hinfo; @@ -968,14 +968,13 @@ static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, struct buffer_head *bh; unsigned long block; int retval; - int namelen = dentry->d_name.len; - const u8 *name = dentry->d_name.name; - struct inode *dir = dentry->d_parent->d_inode; + int namelen = entry->len; + const u8 *name = entry->name; sb = dir->i_sb; /* NFS may look up ".." - look at dx_root directory block */ - if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){ - if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err))) + if (namelen > 2 || name[0] != '.'|| (namelen == 2 && name[1] != '.')) { + if (!(frame = dx_probe(entry, dir, &hinfo, frames, err))) return NULL; } else { frame = frames; @@ -1036,7 +1035,7 @@ static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, str if (dentry->d_name.len > EXT3_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); - bh = ext3_find_entry(dentry, &de); + bh = ext3_find_entry(dir, &dentry->d_name, &de); inode = NULL; if (bh) { unsigned long ino = le32_to_cpu(de->inode); @@ -1057,15 +1056,11 @@ static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, str struct dentry *ext3_get_parent(struct dentry *child) { unsigned long ino; - struct dentry dotdot; + struct qstr dotdot = {.name = "..", .len = 2}; struct ext3_dir_entry_2 * de; struct buffer_head *bh; - dotdot.d_name.name = ".."; - dotdot.d_name.len = 2; - dotdot.d_parent = child; /* confusing, isn't it! */ - - bh = ext3_find_entry(&dotdot, &de); + bh = ext3_find_entry(child->d_inode, &dotdot, &de); if (!bh) return ERR_PTR(-ENOENT); ino = le32_to_cpu(de->inode); @@ -1491,7 +1486,7 @@ static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, struct ext3_dir_entry_2 *de; int err; - frame = dx_probe(dentry, NULL, &hinfo, frames, &err); + frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err); if (!frame) return err; entries = frame->entries; @@ -2044,7 +2039,7 @@ static int ext3_rmdir (struct inode * dir, struct dentry *dentry) return PTR_ERR(handle); retval = -ENOENT; - bh = ext3_find_entry (dentry, &de); + bh = ext3_find_entry(dir, &dentry->d_name, &de); if (!bh) goto end_rmdir; @@ -2106,7 +2101,7 @@ static int ext3_unlink(struct inode * dir, struct dentry *dentry) handle->h_sync = 1; retval = -ENOENT; - bh = ext3_find_entry (dentry, &de); + bh = ext3_find_entry(dir, &dentry->d_name, &de); if (!bh) goto end_unlink; @@ -2264,7 +2259,7 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) handle->h_sync = 1; - old_bh = ext3_find_entry (old_dentry, &old_de); + old_bh = ext3_find_entry(old_dir, &old_dentry->d_name, &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 @@ -2277,7 +2272,7 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, goto end_rename; new_inode = new_dentry->d_inode; - new_bh = ext3_find_entry (new_dentry, &new_de); + new_bh = ext3_find_entry(new_dir, &new_dentry->d_name, &new_de); if (new_bh) { if (!new_inode) { brelse (new_bh); @@ -2343,7 +2338,8 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, struct buffer_head *old_bh2; struct ext3_dir_entry_2 *old_de2; - old_bh2 = ext3_find_entry(old_dentry, &old_de2); + old_bh2 = ext3_find_entry(old_dir, &old_dentry->d_name, + &old_de2); if (old_bh2) { retval = ext3_delete_entry(handle, old_dir, old_de2, old_bh2); -- cgit v1.2.3