diff options
| -rw-r--r-- | fs/hfsplus/attributes.c | 399 |
1 files changed, 399 insertions, 0 deletions
diff --git a/fs/hfsplus/attributes.c b/fs/hfsplus/attributes.c new file mode 100644 index 0000000..8d691f1 --- /dev/null +++ b/fs/hfsplus/attributes.c @@ -0,0 +1,399 @@ +/* + * linux/fs/hfsplus/attributes.c + * + * Vyacheslav Dubeyko <slava@dubeyko.com> + * + * Handling of records in attributes tree + */ + +#include "hfsplus_fs.h" +#include "hfsplus_raw.h" + +static struct kmem_cache *hfsplus_attr_tree_cachep; + +int hfsplus_create_attr_tree_cache(void) +{ + if (hfsplus_attr_tree_cachep) + return -EEXIST; + + hfsplus_attr_tree_cachep = + kmem_cache_create("hfsplus_attr_cache", + sizeof(hfsplus_attr_entry), 0, + SLAB_HWCACHE_ALIGN, NULL); + if (!hfsplus_attr_tree_cachep) + return -ENOMEM; + + return 0; +} + +void hfsplus_destroy_attr_tree_cache(void) +{ + kmem_cache_destroy(hfsplus_attr_tree_cachep); +} + +int hfsplus_attr_bin_cmp_key(const hfsplus_btree_key *k1, + const hfsplus_btree_key *k2) +{ + __be32 k1_cnid, k2_cnid; + + k1_cnid = k1->attr.cnid; + k2_cnid = k2->attr.cnid; + if (k1_cnid != k2_cnid) + return be32_to_cpu(k1_cnid) < be32_to_cpu(k2_cnid) ? -1 : 1; + + return hfsplus_strcmp( + (const struct hfsplus_unistr *)&k1->attr.key_name, + (const struct hfsplus_unistr *)&k2->attr.key_name); +} + +int hfsplus_attr_build_key(struct super_block *sb, hfsplus_btree_key *key, + u32 cnid, const char *name) +{ + int len; + + memset(key, 0, sizeof(struct hfsplus_attr_key)); + key->attr.cnid = cpu_to_be32(cnid); + if (name) { + len = strlen(name); + if (len > HFSPLUS_ATTR_MAX_STRLEN) { + printk(KERN_ERR "hfs: invalid xattr name's length\n"); + return -EINVAL; + } + hfsplus_asc2uni(sb, + (struct hfsplus_unistr *)&key->attr.key_name, + HFSPLUS_ATTR_MAX_STRLEN, name, len); + len = be16_to_cpu(key->attr.key_name.length); + } else { + key->attr.key_name.length = 0; + len = 0; + } + + /* The length of the key, as stored in key_len field, does not include + * the size of the key_len field itself. + * So, offsetof(hfsplus_attr_key, key_name) is a trick because + * it takes into consideration key_len field (__be16) of + * hfsplus_attr_key structure instead of length field (__be16) of + * hfsplus_attr_unistr structure. + */ + key->key_len = + cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) + + 2 * len); + + return 0; +} + +void hfsplus_attr_build_key_uni(hfsplus_btree_key *key, + u32 cnid, + struct hfsplus_attr_unistr *name) +{ + int ustrlen; + + memset(key, 0, sizeof(struct hfsplus_attr_key)); + ustrlen = be16_to_cpu(name->length); + key->attr.cnid = cpu_to_be32(cnid); + key->attr.key_name.length = cpu_to_be16(ustrlen); + ustrlen *= 2; + memcpy(key->attr.key_name.unicode, name->unicode, ustrlen); + + /* The length of the key, as stored in key_len field, does not include + * the size of the key_len field itself. + * So, offsetof(hfsplus_attr_key, key_name) is a trick because + * it takes into consideration key_len field (__be16) of + * hfsplus_attr_key structure instead of length field (__be16) of + * hfsplus_attr_unistr structure. + */ + key->key_len = + cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) + + ustrlen); +} + +hfsplus_attr_entry *hfsplus_alloc_attr_entry(void) +{ + return kmem_cache_alloc(hfsplus_attr_tree_cachep, GFP_KERNEL); +} + +void hfsplus_destroy_attr_entry(hfsplus_attr_entry *entry) +{ + if (entry) + kmem_cache_free(hfsplus_attr_tree_cachep, entry); +} + +#define HFSPLUS_INVALID_ATTR_RECORD -1 + +static int hfsplus_attr_build_record(hfsplus_attr_entry *entry, int record_type, + u32 cnid, const void *value, size_t size) +{ + if (record_type == HFSPLUS_ATTR_FORK_DATA) { + /* + * Mac OS X supports only inline data attributes. + * Do nothing + */ + memset(entry, 0, sizeof(*entry)); + return sizeof(struct hfsplus_attr_fork_data); + } else if (record_type == HFSPLUS_ATTR_EXTENTS) { + /* + * Mac OS X supports only inline data attributes. + * Do nothing. + */ + memset(entry, 0, sizeof(*entry)); + return sizeof(struct hfsplus_attr_extents); + } else if (record_type == HFSPLUS_ATTR_INLINE_DATA) { + u16 len; + + memset(entry, 0, sizeof(struct hfsplus_attr_inline_data)); + entry->inline_data.record_type = cpu_to_be32(record_type); + if (size <= HFSPLUS_MAX_INLINE_DATA_SIZE) + len = size; + else + return HFSPLUS_INVALID_ATTR_RECORD; + entry->inline_data.length = cpu_to_be16(len); + memcpy(entry->inline_data.raw_bytes, value, len); + /* + * Align len on two-byte boundary. + * It needs to add pad byte if we have odd len. + */ + len = round_up(len, 2); + return offsetof(struct hfsplus_attr_inline_data, raw_bytes) + + len; + } else /* invalid input */ + memset(entry, 0, sizeof(*entry)); + + return HFSPLUS_INVALID_ATTR_RECORD; +} + +int hfsplus_find_attr(struct super_block *sb, u32 cnid, + const char *name, struct hfs_find_data *fd) +{ + int err = 0; + + dprint(DBG_ATTR_MOD, "find_attr: %s,%d\n", name ? name : NULL, cnid); + + if (!HFSPLUS_SB(sb)->attr_tree) { + printk(KERN_ERR "hfs: attributes file doesn't exist\n"); + return -EINVAL; + } + + if (name) { + err = hfsplus_attr_build_key(sb, fd->search_key, cnid, name); + if (err) + goto failed_find_attr; + err = hfs_brec_find(fd, hfs_find_rec_by_key); + if (err) + goto failed_find_attr; + } else { + err = hfsplus_attr_build_key(sb, fd->search_key, cnid, NULL); + if (err) + goto failed_find_attr; + err = hfs_brec_find(fd, hfs_find_1st_rec_by_cnid); + if (err) + goto failed_find_attr; + } + +failed_find_attr: + return err; +} + +int hfsplus_attr_exists(struct inode *inode, const char *name) +{ + int err = 0; + struct super_block *sb = inode->i_sb; + struct hfs_find_data fd; + + if (!HFSPLUS_SB(sb)->attr_tree) + return 0; + + err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); + if (err) + return 0; + + err = hfsplus_find_attr(sb, inode->i_ino, name, &fd); + if (err) + goto attr_not_found; + + hfs_find_exit(&fd); + return 1; + +attr_not_found: + hfs_find_exit(&fd); + return 0; +} + +int hfsplus_create_attr(struct inode *inode, + const char *name, + const void *value, size_t size) +{ + struct super_block *sb = inode->i_sb; + struct hfs_find_data fd; + hfsplus_attr_entry *entry_ptr; + int entry_size; + int err; + + dprint(DBG_ATTR_MOD, "create_attr: %s,%ld\n", + name ? name : NULL, inode->i_ino); + + if (!HFSPLUS_SB(sb)->attr_tree) { + printk(KERN_ERR "hfs: attributes file doesn't exist\n"); + return -EINVAL; + } + + entry_ptr = hfsplus_alloc_attr_entry(); + if (!entry_ptr) + return -ENOMEM; + + err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); + if (err) + goto failed_init_create_attr; + + if (name) { + err = hfsplus_attr_build_key(sb, fd.search_key, + inode->i_ino, name); + if (err) + goto failed_create_attr; + } else { + err = -EINVAL; + goto failed_create_attr; + } + + /* Mac OS X supports only inline data attributes. */ + entry_size = hfsplus_attr_build_record(entry_ptr, + HFSPLUS_ATTR_INLINE_DATA, + inode->i_ino, + value, size); + if (entry_size == HFSPLUS_INVALID_ATTR_RECORD) { + err = -EINVAL; + goto failed_create_attr; + } + + err = hfs_brec_find(&fd, hfs_find_rec_by_key); + if (err != -ENOENT) { + if (!err) + err = -EEXIST; + goto failed_create_attr; + } + + err = hfs_brec_insert(&fd, entry_ptr, entry_size); + if (err) + goto failed_create_attr; + + hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY); + +failed_create_attr: + hfs_find_exit(&fd); + +failed_init_create_attr: + hfsplus_destroy_attr_entry(entry_ptr); + return err; +} + +static int __hfsplus_delete_attr(struct inode *inode, u32 cnid, + struct hfs_find_data *fd) +{ + int err = 0; + __be32 found_cnid, record_type; + + hfs_bnode_read(fd->bnode, &found_cnid, + fd->keyoffset + + offsetof(struct hfsplus_attr_key, cnid), + sizeof(__be32)); + if (cnid != be32_to_cpu(found_cnid)) + return -ENOENT; + + hfs_bnode_read(fd->bnode, &record_type, + fd->entryoffset, sizeof(record_type)); + + switch (be32_to_cpu(record_type)) { + case HFSPLUS_ATTR_INLINE_DATA: + /* All is OK. Do nothing. */ + break; + case HFSPLUS_ATTR_FORK_DATA: + case HFSPLUS_ATTR_EXTENTS: + printk(KERN_ERR "hfs: only inline data xattr are supported\n"); + return -EOPNOTSUPP; + default: + printk(KERN_ERR "hfs: invalid extended attribute record\n"); + return -ENOENT; + } + + err = hfs_brec_remove(fd); + if (err) + return err; + + hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY); + return err; +} + +int hfsplus_delete_attr(struct inode *inode, const char *name) +{ + int err = 0; + struct super_block *sb = inode->i_sb; + struct hfs_find_data fd; + + dprint(DBG_ATTR_MOD, "delete_attr: %s,%ld\n", + name ? name : NULL, inode->i_ino); + + if (!HFSPLUS_SB(sb)->attr_tree) { + printk(KERN_ERR "hfs: attributes file doesn't exist\n"); + return -EINVAL; + } + + err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); + if (err) + return err; + + if (name) { + err = hfsplus_attr_build_key(sb, fd.search_key, + inode->i_ino, name); + if (err) + goto out; + } else { + printk(KERN_ERR "hfs: invalid extended attribute name\n"); + err = -EINVAL; + goto out; + } + + err = hfs_brec_find(&fd, hfs_find_rec_by_key); + if (err) + goto out; + + err = __hfsplus_delete_attr(inode, inode->i_ino, &fd); + if (err) + goto out; + +out: + hfs_find_exit(&fd); + return err; +} + +int hfsplus_delete_all_attrs(struct inode *dir, u32 cnid) +{ + int err = 0; + struct hfs_find_data fd; + + dprint(DBG_ATTR_MOD, "delete_all_attrs: %d\n", cnid); + + if (!HFSPLUS_SB(dir->i_sb)->attr_tree) { + printk(KERN_ERR "hfs: attributes file doesn't exist\n"); + return -EINVAL; + } + + err = hfs_find_init(HFSPLUS_SB(dir->i_sb)->attr_tree, &fd); + if (err) + return err; + + for (;;) { + err = hfsplus_find_attr(dir->i_sb, cnid, NULL, &fd); + if (err) { + if (err != -ENOENT) + printk(KERN_ERR "hfs: xattr search failed.\n"); + goto end_delete_all; + } + + err = __hfsplus_delete_attr(dir, cnid, &fd); + if (err) + goto end_delete_all; + } + +end_delete_all: + hfs_find_exit(&fd); + return err; +} |
