]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - fs/ext3/namei.c
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[karo-tx-linux.git] / fs / ext3 / namei.c
index 85d132c37ee0f1a8a8c840432d7839f4d9b97af6..ec8170adac5397de65b862fa549e27acdc9ab294 100644 (file)
@@ -35,7 +35,7 @@
 #include <linux/string.h>
 #include <linux/quotaops.h>
 #include <linux/buffer_head.h>
-#include <linux/smp_lock.h>
+#include <linux/bio.h>
 
 #include "namei.h"
 #include "xattr.h"
@@ -140,10 +140,10 @@ struct dx_frame
 struct dx_map_entry
 {
        u32 hash;
-       u32 offs;
+       u16 offs;
+       u16 size;
 };
 
-#ifdef CONFIG_EXT3_INDEX
 static inline unsigned dx_get_block (struct dx_entry *entry);
 static void dx_set_block (struct dx_entry *entry, unsigned value);
 static inline unsigned dx_get_hash (struct dx_entry *entry);
@@ -379,13 +379,28 @@ dx_probe(struct dentry *dentry, struct inode *dir,
 
        entries = (struct dx_entry *) (((char *)&root->info) +
                                       root->info.info_length);
-       assert(dx_get_limit(entries) == dx_root_limit(dir,
-                                                     root->info.info_length));
+
+       if (dx_get_limit(entries) != dx_root_limit(dir,
+                                                  root->info.info_length)) {
+               ext3_warning(dir->i_sb, __FUNCTION__,
+                            "dx entry: limit != root limit");
+               brelse(bh);
+               *err = ERR_BAD_DX_DIR;
+               goto fail;
+       }
+
        dxtrace (printk("Look up %x", hash));
        while (1)
        {
                count = dx_get_count(entries);
-               assert (count && count <= dx_get_limit(entries));
+               if (!count || count > dx_get_limit(entries)) {
+                       ext3_warning(dir->i_sb, __FUNCTION__,
+                                    "dx entry: no count or count > limit");
+                       brelse(bh);
+                       *err = ERR_BAD_DX_DIR;
+                       goto fail2;
+               }
+
                p = entries + 1;
                q = entries + count - 1;
                while (p <= q)
@@ -423,8 +438,15 @@ dx_probe(struct dentry *dentry, struct inode *dir,
                if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err)))
                        goto fail2;
                at = entries = ((struct dx_node *) bh->b_data)->entries;
-               assert (dx_get_limit(entries) == dx_node_limit (dir));
+               if (dx_get_limit(entries) != dx_node_limit (dir)) {
+                       ext3_warning(dir->i_sb, __FUNCTION__,
+                                    "dx entry: limit != node limit");
+                       brelse(bh);
+                       *err = ERR_BAD_DX_DIR;
+                       goto fail2;
+               }
                frame++;
+               frame->bh = NULL;
        }
 fail2:
        while (frame >= frame_in) {
@@ -432,6 +454,10 @@ fail2:
                frame--;
        }
 fail:
+       if (*err == ERR_BAD_DX_DIR)
+               ext3_warning(dir->i_sb, __FUNCTION__,
+                            "Corrupt dir inode %ld, running e2fsck is "
+                            "recommended.", dir->i_ino);
        return NULL;
 }
 
@@ -551,6 +577,15 @@ static int htree_dirblock_to_tree(struct file *dir_file,
                                           dir->i_sb->s_blocksize -
                                           EXT3_DIR_REC_LEN(0));
        for (; de < top; de = ext3_next_entry(de)) {
+               if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
+                                       (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb))
+                                               +((char *)de - bh->b_data))) {
+                       /* On error, skip the f_pos to the next block. */
+                       dir_file->f_pos = (dir_file->f_pos |
+                                       (dir->i_sb->s_blocksize - 1)) + 1;
+                       brelse (bh);
+                       return count;
+               }
                ext3fs_dirhash(de->name, de->name_len, hinfo);
                if ((hinfo->hash < start_hash) ||
                    ((hinfo->hash == start_hash) &&
@@ -592,7 +627,7 @@ int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 
        dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
                       start_minor_hash));
-       dir = dir_file->f_dentry->d_inode;
+       dir = dir_file->f_path.dentry->d_inode;
        if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) {
                hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
                hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
@@ -603,7 +638,7 @@ int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
        }
        hinfo.hash = start_hash;
        hinfo.minor_hash = 0;
-       frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err);
+       frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err);
        if (!frame)
                return err;
 
@@ -662,6 +697,10 @@ errout:
  * Directory block splitting, compacting
  */
 
+/*
+ * Create map of hash values, offsets, and sizes, stored at end of block.
+ * Returns number of entries mapped.
+ */
 static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
                        struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
 {
@@ -675,7 +714,8 @@ static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
                        ext3fs_dirhash(de->name, de->name_len, &h);
                        map_tail--;
                        map_tail->hash = h.hash;
-                       map_tail->offs = (u32) ((char *) de - base);
+                       map_tail->offs = (u16) ((char *) de - base);
+                       map_tail->size = le16_to_cpu(de->rec_len);
                        count++;
                        cond_resched();
                }
@@ -685,6 +725,7 @@ static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
        return count;
 }
 
+/* Sort map by hash value */
 static void dx_sort_map (struct dx_map_entry *map, unsigned count)
 {
         struct dx_map_entry *p, *q, *top = map + count - 1;
@@ -726,8 +767,6 @@ static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
        dx_set_block(new, block);
        dx_set_count(entries, count + 1);
 }
-#endif
-
 
 static void ext3_update_dx_flag(struct inode *inode)
 {
@@ -829,7 +868,6 @@ static struct buffer_head * ext3_find_entry (struct dentry *dentry,
        name = dentry->d_name.name;
        if (namelen > EXT3_NAME_LEN)
                return NULL;
-#ifdef CONFIG_EXT3_INDEX
        if (is_dx(dir)) {
                bh = ext3_dx_find_entry(dentry, res_dir, &err);
                /*
@@ -841,7 +879,6 @@ static struct buffer_head * ext3_find_entry (struct dentry *dentry,
                        return bh;
                dxtrace(printk("ext3_find_entry: dx failed, falling back\n"));
        }
-#endif
        nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
        start = EXT3_I(dir)->i_dir_start_lookup;
        if (start >= nblocks)
@@ -870,7 +907,7 @@ restart:
                                bh = ext3_getblk(NULL, dir, b++, 0, &err);
                                bh_use[ra_max] = bh;
                                if (bh)
-                                       ll_rw_block(READ, 1, &bh);
+                                       ll_rw_block(READ_META, 1, &bh);
                        }
                }
                if ((bh = bh_use[ra_ptr++]) == NULL)
@@ -917,7 +954,6 @@ cleanup_and_exit:
        return ret;
 }
 
-#ifdef CONFIG_EXT3_INDEX
 static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
                       struct ext3_dir_entry_2 **res_dir, int *err)
 {
@@ -959,6 +995,7 @@ static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
                                  (block<<EXT3_BLOCK_SIZE_BITS(sb))
                                          +((char *)de - bh->b_data))) {
                                brelse (bh);
+                               *err = ERR_BAD_DX_DIR;
                                goto errout;
                        }
                        *res_dir = de;
@@ -984,7 +1021,6 @@ errout:
        dx_release (frames);
        return NULL;
 }
-#endif
 
 static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
 {
@@ -1009,6 +1045,11 @@ static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, str
 
                if (!inode)
                        return ERR_PTR(-EACCES);
+
+               if (is_bad_inode(inode)) {
+                       iput(inode);
+                       return ERR_PTR(-ENOENT);
+               }
        }
        return d_splice_alias(inode, dentry);
 }
@@ -1044,6 +1085,11 @@ struct dentry *ext3_get_parent(struct dentry *child)
        if (!inode)
                return ERR_PTR(-EACCES);
 
+       if (is_bad_inode(inode)) {
+               iput(inode);
+               return ERR_PTR(-ENOENT);
+       }
+
        parent = d_alloc_anon(inode);
        if (!parent) {
                iput(inode);
@@ -1070,7 +1116,10 @@ static inline void ext3_set_de_type(struct super_block *sb,
                de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
 }
 
-#ifdef CONFIG_EXT3_INDEX
+/*
+ * Move count entries from end of map between two memory locations.
+ * Returns pointer to last entry moved.
+ */
 static struct ext3_dir_entry_2 *
 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
 {
@@ -1089,6 +1138,10 @@ dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
        return (struct ext3_dir_entry_2 *) (to - rec_len);
 }
 
+/*
+ * Compact each dir entry in the range to the minimal rec_len.
+ * Returns pointer to last entry in range.
+ */
 static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size)
 {
        struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base;
@@ -1111,6 +1164,11 @@ static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size)
        return prev;
 }
 
+/*
+ * Split a full leaf block to make room for a new dir entry.
+ * Allocate a new block, and move entries so that they are approx. equally full.
+ * Returns pointer to de in block into which the new entry will be inserted.
+ */
 static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
                        struct buffer_head **bh,struct dx_frame *frame,
                        struct dx_hash_info *hinfo, int *error)
@@ -1122,11 +1180,11 @@ static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
        u32 hash2;
        struct dx_map_entry *map;
        char *data1 = (*bh)->b_data, *data2;
-       unsigned split;
+       unsigned split, move, size, i;
        struct ext3_dir_entry_2 *de = NULL, *de2;
-       int     err;
+       int     err = 0;
 
-       bh2 = ext3_append (handle, dir, &newblock, error);
+       bh2 = ext3_append (handle, dir, &newblock, &err);
        if (!(bh2)) {
                brelse(*bh);
                *bh = NULL;
@@ -1135,14 +1193,9 @@ static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
 
        BUFFER_TRACE(*bh, "get_write_access");
        err = ext3_journal_get_write_access(handle, *bh);
-       if (err) {
-       journal_error:
-               brelse(*bh);
-               brelse(bh2);
-               *bh = NULL;
-               ext3_std_error(dir->i_sb, err);
-               goto errout;
-       }
+       if (err)
+               goto journal_error;
+
        BUFFER_TRACE(frame->bh, "get_write_access");
        err = ext3_journal_get_write_access(handle, frame->bh);
        if (err)
@@ -1155,8 +1208,19 @@ static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
        count = dx_make_map ((struct ext3_dir_entry_2 *) data1,
                             blocksize, hinfo, map);
        map -= count;
-       split = count/2; // need to adjust to actual middle
        dx_sort_map (map, count);
+       /* Split the existing block in the middle, size-wise */
+       size = 0;
+       move = 0;
+       for (i = count-1; i >= 0; i--) {
+               /* is more than half of this entry in 2nd half of the block? */
+               if (size + map[i].size/2 > blocksize/2)
+                       break;
+               size += map[i].size;
+               move++;
+       }
+       /* map index at which we will split */
+       split = count - move;
        hash2 = map[split].hash;
        continued = hash2 == map[split - 1].hash;
        dxtrace(printk("Split block %i at %x, %i/%i\n",
@@ -1185,10 +1249,17 @@ static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
                goto journal_error;
        brelse (bh2);
        dxtrace(dx_show_index ("frame", frame->entries));
-errout:
        return de;
+
+journal_error:
+       brelse(*bh);
+       brelse(bh2);
+       *bh = NULL;
+       ext3_std_error(dir->i_sb, err);
+errout:
+       *error = err;
+       return NULL;
 }
-#endif
 
 
 /*
@@ -1286,7 +1357,6 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
        return 0;
 }
 
-#ifdef CONFIG_EXT3_INDEX
 /*
  * This converts a one block unindexed directory to a 3 block indexed
  * directory, and adds the dentry to the indexed directory.
@@ -1365,7 +1435,6 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
 
        return add_dirent_to_buf(handle, dentry, inode, de, bh);
 }
-#endif
 
 /*
  *     ext3_add_entry()
@@ -1386,9 +1455,7 @@ static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
        struct ext3_dir_entry_2 *de;
        struct super_block * sb;
        int     retval;
-#ifdef CONFIG_EXT3_INDEX
        int     dx_fallback=0;
-#endif
        unsigned blocksize;
        u32 block, blocks;
 
@@ -1396,7 +1463,6 @@ static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
        blocksize = sb->s_blocksize;
        if (!dentry->d_name.len)
                return -EINVAL;
-#ifdef CONFIG_EXT3_INDEX
        if (is_dx(dir)) {
                retval = ext3_dx_add_entry(handle, dentry, inode);
                if (!retval || (retval != ERR_BAD_DX_DIR))
@@ -1405,7 +1471,6 @@ static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
                dx_fallback++;
                ext3_mark_inode_dirty(handle, dir);
        }
-#endif
        blocks = dir->i_size >> sb->s_blocksize_bits;
        for (block = 0, offset = 0; block < blocks; block++) {
                bh = ext3_bread(handle, dir, block, 0, &retval);
@@ -1415,11 +1480,9 @@ static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
                if (retval != -ENOSPC)
                        return retval;
 
-#ifdef CONFIG_EXT3_INDEX
                if (blocks == 1 && !dx_fallback &&
                    EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
                        return make_indexed_dir(handle, dentry, inode, bh);
-#endif
                brelse(bh);
        }
        bh = ext3_append(handle, dir, &block, &retval);
@@ -1431,7 +1494,6 @@ static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
        return add_dirent_to_buf(handle, dentry, inode, de, bh);
 }
 
-#ifdef CONFIG_EXT3_INDEX
 /*
  * Returns 0 for success, or a negative error value
  */
@@ -1566,7 +1628,6 @@ cleanup:
        dx_release(frames);
        return err;
 }
-#endif
 
 /*
  * ext3_delete_entry deletes a directory entry by merging it with the
@@ -1608,21 +1669,6 @@ static int ext3_delete_entry (handle_t *handle,
        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)
 {
@@ -1632,7 +1678,7 @@ static int ext3_add_nondir(handle_t *handle,
                d_instantiate(dentry, inode);
                return 0;
        }
-       ext3_dec_count(handle, inode);
+       drop_nlink(inode);
        iput(inode);
        return err;
 }
@@ -1742,7 +1788,7 @@ retry:
        inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize;
        dir_block = ext3_bread (handle, inode, 0, 1, &err);
        if (!dir_block) {
-               inode->i_nlink--; /* is this nlink == 0? */
+               drop_nlink(inode); /* is this nlink == 0? */
                ext3_mark_inode_dirty(handle, inode);
                iput (inode);
                goto out_stop;
@@ -1774,7 +1820,7 @@ retry:
                iput (inode);
                goto out_stop;
        }
-       dir->i_nlink++;
+       inc_nlink(dir);
        ext3_update_dx_flag(dir);
        ext3_mark_inode_dirty(handle, dir);
        d_instantiate(dentry, inode);
@@ -2044,7 +2090,7 @@ static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
                              "empty directory has nlink!=2 (%d)",
                              inode->i_nlink);
        inode->i_version++;
-       inode->i_nlink = 0;
+       clear_nlink(inode);
        /* 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. */
@@ -2052,7 +2098,7 @@ static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
        ext3_orphan_add(handle, inode);
        inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
        ext3_mark_inode_dirty(handle, inode);
-       dir->i_nlink--;
+       drop_nlink(dir);
        ext3_update_dx_flag(dir);
        ext3_mark_inode_dirty(handle, dir);
 
@@ -2103,7 +2149,7 @@ static int ext3_unlink(struct inode * dir, struct dentry *dentry)
        dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
        ext3_update_dx_flag(dir);
        ext3_mark_inode_dirty(handle, dir);
-       inode->i_nlink--;
+       drop_nlink(inode);
        if (!inode->i_nlink)
                ext3_orphan_add(handle, inode);
        inode->i_ctime = dir->i_ctime;
@@ -2153,7 +2199,7 @@ retry:
                err = __page_symlink(inode, symname, l,
                                mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
                if (err) {
-                       ext3_dec_count(handle, inode);
+                       drop_nlink(inode);
                        ext3_mark_inode_dirty(handle, inode);
                        iput (inode);
                        goto out_stop;
@@ -2181,6 +2227,12 @@ static int ext3_link (struct dentry * old_dentry,
 
        if (inode->i_nlink >= EXT3_LINK_MAX)
                return -EMLINK;
+       /*
+        * Return -ENOENT if we've raced with unlink and i_nlink is 0.  Doing
+        * otherwise has the potential to corrupt the orphan inode list.
+        */
+       if (inode->i_nlink == 0)
+               return -ENOENT;
 
 retry:
        handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
@@ -2192,7 +2244,7 @@ retry:
                handle->h_sync = 1;
 
        inode->i_ctime = CURRENT_TIME_SEC;
-       ext3_inc_count(handle, inode);
+       inc_nlink(inode);
        atomic_inc(&inode->i_count);
 
        err = ext3_add_nondir(handle, dentry, inode);
@@ -2325,7 +2377,7 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
        }
 
        if (new_inode) {
-               new_inode->i_nlink--;
+               drop_nlink(new_inode);
                new_inode->i_ctime = CURRENT_TIME_SEC;
        }
        old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
@@ -2336,11 +2388,11 @@ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
                PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
                BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
                ext3_journal_dirty_metadata(handle, dir_bh);
-               old_dir->i_nlink--;
+               drop_nlink(old_dir);
                if (new_inode) {
-                       new_inode->i_nlink--;
+                       drop_nlink(new_inode);
                } else {
-                       new_dir->i_nlink++;
+                       inc_nlink(new_dir);
                        ext3_update_dx_flag(new_dir);
                        ext3_mark_inode_dirty(handle, new_dir);
                }
@@ -2364,7 +2416,7 @@ end_rename:
 /*
  * directories can handle most operations...
  */
-struct inode_operations ext3_dir_inode_operations = {
+const struct inode_operations ext3_dir_inode_operations = {
        .create         = ext3_create,
        .lookup         = ext3_lookup,
        .link           = ext3_link,
@@ -2384,7 +2436,7 @@ struct inode_operations ext3_dir_inode_operations = {
        .permission     = ext3_permission,
 };
 
-struct inode_operations ext3_special_inode_operations = {
+const struct inode_operations ext3_special_inode_operations = {
        .setattr        = ext3_setattr,
 #ifdef CONFIG_EXT3_FS_XATTR
        .setxattr       = generic_setxattr,