1ac27a0ecSDave Kleikamp /* 2617ba13bSMingming Cao * linux/fs/ext4/xattr.c 3ac27a0ecSDave Kleikamp * 4ac27a0ecSDave Kleikamp * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> 5ac27a0ecSDave Kleikamp * 6ac27a0ecSDave Kleikamp * Fix by Harrison Xing <harrison@mountainviewdata.com>. 7617ba13bSMingming Cao * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>. 8ac27a0ecSDave Kleikamp * Extended attributes for symlinks and special files added per 9ac27a0ecSDave Kleikamp * suggestion of Luka Renko <luka.renko@hermes.si>. 10ac27a0ecSDave Kleikamp * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, 11ac27a0ecSDave Kleikamp * Red Hat Inc. 12ac27a0ecSDave Kleikamp * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz 13ac27a0ecSDave Kleikamp * and Andreas Gruenbacher <agruen@suse.de>. 14ac27a0ecSDave Kleikamp */ 15ac27a0ecSDave Kleikamp 16ac27a0ecSDave Kleikamp /* 17ac27a0ecSDave Kleikamp * Extended attributes are stored directly in inodes (on file systems with 18ac27a0ecSDave Kleikamp * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl 19ac27a0ecSDave Kleikamp * field contains the block number if an inode uses an additional block. All 20ac27a0ecSDave Kleikamp * attributes must fit in the inode and one additional block. Blocks that 21ac27a0ecSDave Kleikamp * contain the identical set of attributes may be shared among several inodes. 22ac27a0ecSDave Kleikamp * Identical blocks are detected by keeping a cache of blocks that have 23ac27a0ecSDave Kleikamp * recently been accessed. 24ac27a0ecSDave Kleikamp * 25ac27a0ecSDave Kleikamp * The attributes in inodes and on blocks have a different header; the entries 26ac27a0ecSDave Kleikamp * are stored in the same format: 27ac27a0ecSDave Kleikamp * 28ac27a0ecSDave Kleikamp * +------------------+ 29ac27a0ecSDave Kleikamp * | header | 30ac27a0ecSDave Kleikamp * | entry 1 | | 31ac27a0ecSDave Kleikamp * | entry 2 | | growing downwards 32ac27a0ecSDave Kleikamp * | entry 3 | v 33ac27a0ecSDave Kleikamp * | four null bytes | 34ac27a0ecSDave Kleikamp * | . . . | 35ac27a0ecSDave Kleikamp * | value 1 | ^ 36ac27a0ecSDave Kleikamp * | value 3 | | growing upwards 37ac27a0ecSDave Kleikamp * | value 2 | | 38ac27a0ecSDave Kleikamp * +------------------+ 39ac27a0ecSDave Kleikamp * 40ac27a0ecSDave Kleikamp * The header is followed by multiple entry descriptors. In disk blocks, the 41ac27a0ecSDave Kleikamp * entry descriptors are kept sorted. In inodes, they are unsorted. The 42ac27a0ecSDave Kleikamp * attribute values are aligned to the end of the block in no specific order. 43ac27a0ecSDave Kleikamp * 44ac27a0ecSDave Kleikamp * Locking strategy 45ac27a0ecSDave Kleikamp * ---------------- 46617ba13bSMingming Cao * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem. 47ac27a0ecSDave Kleikamp * EA blocks are only changed if they are exclusive to an inode, so 48ac27a0ecSDave Kleikamp * holding xattr_sem also means that nothing but the EA block's reference 49ac27a0ecSDave Kleikamp * count can change. Multiple writers to the same block are synchronized 50ac27a0ecSDave Kleikamp * by the buffer lock. 51ac27a0ecSDave Kleikamp */ 52ac27a0ecSDave Kleikamp 53ac27a0ecSDave Kleikamp #include <linux/init.h> 54ac27a0ecSDave Kleikamp #include <linux/fs.h> 55ac27a0ecSDave Kleikamp #include <linux/slab.h> 56dab291afSMingming Cao #include <linux/ext4_jbd2.h> 57617ba13bSMingming Cao #include <linux/ext4_fs.h> 58ac27a0ecSDave Kleikamp #include <linux/mbcache.h> 59ac27a0ecSDave Kleikamp #include <linux/quotaops.h> 60ac27a0ecSDave Kleikamp #include <linux/rwsem.h> 61ac27a0ecSDave Kleikamp #include "xattr.h" 62ac27a0ecSDave Kleikamp #include "acl.h" 63ac27a0ecSDave Kleikamp 64617ba13bSMingming Cao #define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data)) 65617ba13bSMingming Cao #define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr)) 66ac27a0ecSDave Kleikamp #define BFIRST(bh) ENTRY(BHDR(bh)+1) 67ac27a0ecSDave Kleikamp #define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) 68ac27a0ecSDave Kleikamp 69ac27a0ecSDave Kleikamp #define IHDR(inode, raw_inode) \ 70617ba13bSMingming Cao ((struct ext4_xattr_ibody_header *) \ 71ac27a0ecSDave Kleikamp ((void *)raw_inode + \ 72617ba13bSMingming Cao EXT4_GOOD_OLD_INODE_SIZE + \ 73617ba13bSMingming Cao EXT4_I(inode)->i_extra_isize)) 74617ba13bSMingming Cao #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) 75ac27a0ecSDave Kleikamp 76617ba13bSMingming Cao #ifdef EXT4_XATTR_DEBUG 77ac27a0ecSDave Kleikamp # define ea_idebug(inode, f...) do { \ 78ac27a0ecSDave Kleikamp printk(KERN_DEBUG "inode %s:%lu: ", \ 79ac27a0ecSDave Kleikamp inode->i_sb->s_id, inode->i_ino); \ 80ac27a0ecSDave Kleikamp printk(f); \ 81ac27a0ecSDave Kleikamp printk("\n"); \ 82ac27a0ecSDave Kleikamp } while (0) 83ac27a0ecSDave Kleikamp # define ea_bdebug(bh, f...) do { \ 84ac27a0ecSDave Kleikamp char b[BDEVNAME_SIZE]; \ 85ac27a0ecSDave Kleikamp printk(KERN_DEBUG "block %s:%lu: ", \ 86ac27a0ecSDave Kleikamp bdevname(bh->b_bdev, b), \ 87ac27a0ecSDave Kleikamp (unsigned long) bh->b_blocknr); \ 88ac27a0ecSDave Kleikamp printk(f); \ 89ac27a0ecSDave Kleikamp printk("\n"); \ 90ac27a0ecSDave Kleikamp } while (0) 91ac27a0ecSDave Kleikamp #else 92ac27a0ecSDave Kleikamp # define ea_idebug(f...) 93ac27a0ecSDave Kleikamp # define ea_bdebug(f...) 94ac27a0ecSDave Kleikamp #endif 95ac27a0ecSDave Kleikamp 96617ba13bSMingming Cao static void ext4_xattr_cache_insert(struct buffer_head *); 97617ba13bSMingming Cao static struct buffer_head *ext4_xattr_cache_find(struct inode *, 98617ba13bSMingming Cao struct ext4_xattr_header *, 99ac27a0ecSDave Kleikamp struct mb_cache_entry **); 100617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *, 101617ba13bSMingming Cao struct ext4_xattr_entry *); 102ac27a0ecSDave Kleikamp 103617ba13bSMingming Cao static struct mb_cache *ext4_xattr_cache; 104ac27a0ecSDave Kleikamp 105617ba13bSMingming Cao static struct xattr_handler *ext4_xattr_handler_map[] = { 106617ba13bSMingming Cao [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, 107617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL 108617ba13bSMingming Cao [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext4_xattr_acl_access_handler, 109617ba13bSMingming Cao [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext4_xattr_acl_default_handler, 110ac27a0ecSDave Kleikamp #endif 111617ba13bSMingming Cao [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, 112617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_SECURITY 113617ba13bSMingming Cao [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, 114ac27a0ecSDave Kleikamp #endif 115ac27a0ecSDave Kleikamp }; 116ac27a0ecSDave Kleikamp 117617ba13bSMingming Cao struct xattr_handler *ext4_xattr_handlers[] = { 118617ba13bSMingming Cao &ext4_xattr_user_handler, 119617ba13bSMingming Cao &ext4_xattr_trusted_handler, 120617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL 121617ba13bSMingming Cao &ext4_xattr_acl_access_handler, 122617ba13bSMingming Cao &ext4_xattr_acl_default_handler, 123ac27a0ecSDave Kleikamp #endif 124617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_SECURITY 125617ba13bSMingming Cao &ext4_xattr_security_handler, 126ac27a0ecSDave Kleikamp #endif 127ac27a0ecSDave Kleikamp NULL 128ac27a0ecSDave Kleikamp }; 129ac27a0ecSDave Kleikamp 130ac27a0ecSDave Kleikamp static inline struct xattr_handler * 131617ba13bSMingming Cao ext4_xattr_handler(int name_index) 132ac27a0ecSDave Kleikamp { 133ac27a0ecSDave Kleikamp struct xattr_handler *handler = NULL; 134ac27a0ecSDave Kleikamp 135617ba13bSMingming Cao if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) 136617ba13bSMingming Cao handler = ext4_xattr_handler_map[name_index]; 137ac27a0ecSDave Kleikamp return handler; 138ac27a0ecSDave Kleikamp } 139ac27a0ecSDave Kleikamp 140ac27a0ecSDave Kleikamp /* 141ac27a0ecSDave Kleikamp * Inode operation listxattr() 142ac27a0ecSDave Kleikamp * 143ac27a0ecSDave Kleikamp * dentry->d_inode->i_mutex: don't care 144ac27a0ecSDave Kleikamp */ 145ac27a0ecSDave Kleikamp ssize_t 146617ba13bSMingming Cao ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) 147ac27a0ecSDave Kleikamp { 148617ba13bSMingming Cao return ext4_xattr_list(dentry->d_inode, buffer, size); 149ac27a0ecSDave Kleikamp } 150ac27a0ecSDave Kleikamp 151ac27a0ecSDave Kleikamp static int 152617ba13bSMingming Cao ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end) 153ac27a0ecSDave Kleikamp { 154ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry)) { 155617ba13bSMingming Cao struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(entry); 156ac27a0ecSDave Kleikamp if ((void *)next >= end) 157ac27a0ecSDave Kleikamp return -EIO; 158ac27a0ecSDave Kleikamp entry = next; 159ac27a0ecSDave Kleikamp } 160ac27a0ecSDave Kleikamp return 0; 161ac27a0ecSDave Kleikamp } 162ac27a0ecSDave Kleikamp 163ac27a0ecSDave Kleikamp static inline int 164617ba13bSMingming Cao ext4_xattr_check_block(struct buffer_head *bh) 165ac27a0ecSDave Kleikamp { 166ac27a0ecSDave Kleikamp int error; 167ac27a0ecSDave Kleikamp 168617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 169ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) 170ac27a0ecSDave Kleikamp return -EIO; 171617ba13bSMingming Cao error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size); 172ac27a0ecSDave Kleikamp return error; 173ac27a0ecSDave Kleikamp } 174ac27a0ecSDave Kleikamp 175ac27a0ecSDave Kleikamp static inline int 176617ba13bSMingming Cao ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) 177ac27a0ecSDave Kleikamp { 178ac27a0ecSDave Kleikamp size_t value_size = le32_to_cpu(entry->e_value_size); 179ac27a0ecSDave Kleikamp 180ac27a0ecSDave Kleikamp if (entry->e_value_block != 0 || value_size > size || 181ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs) + value_size > size) 182ac27a0ecSDave Kleikamp return -EIO; 183ac27a0ecSDave Kleikamp return 0; 184ac27a0ecSDave Kleikamp } 185ac27a0ecSDave Kleikamp 186ac27a0ecSDave Kleikamp static int 187617ba13bSMingming Cao ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, 188ac27a0ecSDave Kleikamp const char *name, size_t size, int sorted) 189ac27a0ecSDave Kleikamp { 190617ba13bSMingming Cao struct ext4_xattr_entry *entry; 191ac27a0ecSDave Kleikamp size_t name_len; 192ac27a0ecSDave Kleikamp int cmp = 1; 193ac27a0ecSDave Kleikamp 194ac27a0ecSDave Kleikamp if (name == NULL) 195ac27a0ecSDave Kleikamp return -EINVAL; 196ac27a0ecSDave Kleikamp name_len = strlen(name); 197ac27a0ecSDave Kleikamp entry = *pentry; 198617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 199ac27a0ecSDave Kleikamp cmp = name_index - entry->e_name_index; 200ac27a0ecSDave Kleikamp if (!cmp) 201ac27a0ecSDave Kleikamp cmp = name_len - entry->e_name_len; 202ac27a0ecSDave Kleikamp if (!cmp) 203ac27a0ecSDave Kleikamp cmp = memcmp(name, entry->e_name, name_len); 204ac27a0ecSDave Kleikamp if (cmp <= 0 && (sorted || cmp == 0)) 205ac27a0ecSDave Kleikamp break; 206ac27a0ecSDave Kleikamp } 207ac27a0ecSDave Kleikamp *pentry = entry; 208617ba13bSMingming Cao if (!cmp && ext4_xattr_check_entry(entry, size)) 209ac27a0ecSDave Kleikamp return -EIO; 210ac27a0ecSDave Kleikamp return cmp ? -ENODATA : 0; 211ac27a0ecSDave Kleikamp } 212ac27a0ecSDave Kleikamp 213ac27a0ecSDave Kleikamp static int 214617ba13bSMingming Cao ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, 215ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 216ac27a0ecSDave Kleikamp { 217ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 218617ba13bSMingming Cao struct ext4_xattr_entry *entry; 219ac27a0ecSDave Kleikamp size_t size; 220ac27a0ecSDave Kleikamp int error; 221ac27a0ecSDave Kleikamp 222ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", 223ac27a0ecSDave Kleikamp name_index, name, buffer, (long)buffer_size); 224ac27a0ecSDave Kleikamp 225ac27a0ecSDave Kleikamp error = -ENODATA; 226617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 227ac27a0ecSDave Kleikamp goto cleanup; 228617ba13bSMingming Cao ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl); 229617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 230ac27a0ecSDave Kleikamp if (!bh) 231ac27a0ecSDave Kleikamp goto cleanup; 232ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 233ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 234617ba13bSMingming Cao if (ext4_xattr_check_block(bh)) { 235617ba13bSMingming Cao bad_block: ext4_error(inode->i_sb, __FUNCTION__, 236*2ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 237617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 238ac27a0ecSDave Kleikamp error = -EIO; 239ac27a0ecSDave Kleikamp goto cleanup; 240ac27a0ecSDave Kleikamp } 241617ba13bSMingming Cao ext4_xattr_cache_insert(bh); 242ac27a0ecSDave Kleikamp entry = BFIRST(bh); 243617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); 244ac27a0ecSDave Kleikamp if (error == -EIO) 245ac27a0ecSDave Kleikamp goto bad_block; 246ac27a0ecSDave Kleikamp if (error) 247ac27a0ecSDave Kleikamp goto cleanup; 248ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 249ac27a0ecSDave Kleikamp if (buffer) { 250ac27a0ecSDave Kleikamp error = -ERANGE; 251ac27a0ecSDave Kleikamp if (size > buffer_size) 252ac27a0ecSDave Kleikamp goto cleanup; 253ac27a0ecSDave Kleikamp memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), 254ac27a0ecSDave Kleikamp size); 255ac27a0ecSDave Kleikamp } 256ac27a0ecSDave Kleikamp error = size; 257ac27a0ecSDave Kleikamp 258ac27a0ecSDave Kleikamp cleanup: 259ac27a0ecSDave Kleikamp brelse(bh); 260ac27a0ecSDave Kleikamp return error; 261ac27a0ecSDave Kleikamp } 262ac27a0ecSDave Kleikamp 263ac27a0ecSDave Kleikamp static int 264617ba13bSMingming Cao ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, 265ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 266ac27a0ecSDave Kleikamp { 267617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 268617ba13bSMingming Cao struct ext4_xattr_entry *entry; 269617ba13bSMingming Cao struct ext4_inode *raw_inode; 270617ba13bSMingming Cao struct ext4_iloc iloc; 271ac27a0ecSDave Kleikamp size_t size; 272ac27a0ecSDave Kleikamp void *end; 273ac27a0ecSDave Kleikamp int error; 274ac27a0ecSDave Kleikamp 275617ba13bSMingming Cao if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)) 276ac27a0ecSDave Kleikamp return -ENODATA; 277617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 278ac27a0ecSDave Kleikamp if (error) 279ac27a0ecSDave Kleikamp return error; 280617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 281ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 282ac27a0ecSDave Kleikamp entry = IFIRST(header); 283617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 284617ba13bSMingming Cao error = ext4_xattr_check_names(entry, end); 285ac27a0ecSDave Kleikamp if (error) 286ac27a0ecSDave Kleikamp goto cleanup; 287617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, 288ac27a0ecSDave Kleikamp end - (void *)entry, 0); 289ac27a0ecSDave Kleikamp if (error) 290ac27a0ecSDave Kleikamp goto cleanup; 291ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 292ac27a0ecSDave Kleikamp if (buffer) { 293ac27a0ecSDave Kleikamp error = -ERANGE; 294ac27a0ecSDave Kleikamp if (size > buffer_size) 295ac27a0ecSDave Kleikamp goto cleanup; 296ac27a0ecSDave Kleikamp memcpy(buffer, (void *)IFIRST(header) + 297ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs), size); 298ac27a0ecSDave Kleikamp } 299ac27a0ecSDave Kleikamp error = size; 300ac27a0ecSDave Kleikamp 301ac27a0ecSDave Kleikamp cleanup: 302ac27a0ecSDave Kleikamp brelse(iloc.bh); 303ac27a0ecSDave Kleikamp return error; 304ac27a0ecSDave Kleikamp } 305ac27a0ecSDave Kleikamp 306ac27a0ecSDave Kleikamp /* 307617ba13bSMingming Cao * ext4_xattr_get() 308ac27a0ecSDave Kleikamp * 309ac27a0ecSDave Kleikamp * Copy an extended attribute into the buffer 310ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 311ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 312ac27a0ecSDave Kleikamp * 313ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 314ac27a0ecSDave Kleikamp * used / required on success. 315ac27a0ecSDave Kleikamp */ 316ac27a0ecSDave Kleikamp int 317617ba13bSMingming Cao ext4_xattr_get(struct inode *inode, int name_index, const char *name, 318ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 319ac27a0ecSDave Kleikamp { 320ac27a0ecSDave Kleikamp int error; 321ac27a0ecSDave Kleikamp 322617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 323617ba13bSMingming Cao error = ext4_xattr_ibody_get(inode, name_index, name, buffer, 324ac27a0ecSDave Kleikamp buffer_size); 325ac27a0ecSDave Kleikamp if (error == -ENODATA) 326617ba13bSMingming Cao error = ext4_xattr_block_get(inode, name_index, name, buffer, 327ac27a0ecSDave Kleikamp buffer_size); 328617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 329ac27a0ecSDave Kleikamp return error; 330ac27a0ecSDave Kleikamp } 331ac27a0ecSDave Kleikamp 332ac27a0ecSDave Kleikamp static int 333617ba13bSMingming Cao ext4_xattr_list_entries(struct inode *inode, struct ext4_xattr_entry *entry, 334ac27a0ecSDave Kleikamp char *buffer, size_t buffer_size) 335ac27a0ecSDave Kleikamp { 336ac27a0ecSDave Kleikamp size_t rest = buffer_size; 337ac27a0ecSDave Kleikamp 338617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 339ac27a0ecSDave Kleikamp struct xattr_handler *handler = 340617ba13bSMingming Cao ext4_xattr_handler(entry->e_name_index); 341ac27a0ecSDave Kleikamp 342ac27a0ecSDave Kleikamp if (handler) { 343ac27a0ecSDave Kleikamp size_t size = handler->list(inode, buffer, rest, 344ac27a0ecSDave Kleikamp entry->e_name, 345ac27a0ecSDave Kleikamp entry->e_name_len); 346ac27a0ecSDave Kleikamp if (buffer) { 347ac27a0ecSDave Kleikamp if (size > rest) 348ac27a0ecSDave Kleikamp return -ERANGE; 349ac27a0ecSDave Kleikamp buffer += size; 350ac27a0ecSDave Kleikamp } 351ac27a0ecSDave Kleikamp rest -= size; 352ac27a0ecSDave Kleikamp } 353ac27a0ecSDave Kleikamp } 354ac27a0ecSDave Kleikamp return buffer_size - rest; 355ac27a0ecSDave Kleikamp } 356ac27a0ecSDave Kleikamp 357ac27a0ecSDave Kleikamp static int 358617ba13bSMingming Cao ext4_xattr_block_list(struct inode *inode, char *buffer, size_t buffer_size) 359ac27a0ecSDave Kleikamp { 360ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 361ac27a0ecSDave Kleikamp int error; 362ac27a0ecSDave Kleikamp 363ac27a0ecSDave Kleikamp ea_idebug(inode, "buffer=%p, buffer_size=%ld", 364ac27a0ecSDave Kleikamp buffer, (long)buffer_size); 365ac27a0ecSDave Kleikamp 366ac27a0ecSDave Kleikamp error = 0; 367617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 368ac27a0ecSDave Kleikamp goto cleanup; 369617ba13bSMingming Cao ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl); 370617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 371ac27a0ecSDave Kleikamp error = -EIO; 372ac27a0ecSDave Kleikamp if (!bh) 373ac27a0ecSDave Kleikamp goto cleanup; 374ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 375ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 376617ba13bSMingming Cao if (ext4_xattr_check_block(bh)) { 377617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 378*2ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 379617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 380ac27a0ecSDave Kleikamp error = -EIO; 381ac27a0ecSDave Kleikamp goto cleanup; 382ac27a0ecSDave Kleikamp } 383617ba13bSMingming Cao ext4_xattr_cache_insert(bh); 384617ba13bSMingming Cao error = ext4_xattr_list_entries(inode, BFIRST(bh), buffer, buffer_size); 385ac27a0ecSDave Kleikamp 386ac27a0ecSDave Kleikamp cleanup: 387ac27a0ecSDave Kleikamp brelse(bh); 388ac27a0ecSDave Kleikamp 389ac27a0ecSDave Kleikamp return error; 390ac27a0ecSDave Kleikamp } 391ac27a0ecSDave Kleikamp 392ac27a0ecSDave Kleikamp static int 393617ba13bSMingming Cao ext4_xattr_ibody_list(struct inode *inode, char *buffer, size_t buffer_size) 394ac27a0ecSDave Kleikamp { 395617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 396617ba13bSMingming Cao struct ext4_inode *raw_inode; 397617ba13bSMingming Cao struct ext4_iloc iloc; 398ac27a0ecSDave Kleikamp void *end; 399ac27a0ecSDave Kleikamp int error; 400ac27a0ecSDave Kleikamp 401617ba13bSMingming Cao if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)) 402ac27a0ecSDave Kleikamp return 0; 403617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 404ac27a0ecSDave Kleikamp if (error) 405ac27a0ecSDave Kleikamp return error; 406617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 407ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 408617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 409617ba13bSMingming Cao error = ext4_xattr_check_names(IFIRST(header), end); 410ac27a0ecSDave Kleikamp if (error) 411ac27a0ecSDave Kleikamp goto cleanup; 412617ba13bSMingming Cao error = ext4_xattr_list_entries(inode, IFIRST(header), 413ac27a0ecSDave Kleikamp buffer, buffer_size); 414ac27a0ecSDave Kleikamp 415ac27a0ecSDave Kleikamp cleanup: 416ac27a0ecSDave Kleikamp brelse(iloc.bh); 417ac27a0ecSDave Kleikamp return error; 418ac27a0ecSDave Kleikamp } 419ac27a0ecSDave Kleikamp 420ac27a0ecSDave Kleikamp /* 421617ba13bSMingming Cao * ext4_xattr_list() 422ac27a0ecSDave Kleikamp * 423ac27a0ecSDave Kleikamp * Copy a list of attribute names into the buffer 424ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 425ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 426ac27a0ecSDave Kleikamp * 427ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 428ac27a0ecSDave Kleikamp * used / required on success. 429ac27a0ecSDave Kleikamp */ 430ac27a0ecSDave Kleikamp int 431617ba13bSMingming Cao ext4_xattr_list(struct inode *inode, char *buffer, size_t buffer_size) 432ac27a0ecSDave Kleikamp { 433ac27a0ecSDave Kleikamp int i_error, b_error; 434ac27a0ecSDave Kleikamp 435617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 436617ba13bSMingming Cao i_error = ext4_xattr_ibody_list(inode, buffer, buffer_size); 437ac27a0ecSDave Kleikamp if (i_error < 0) { 438ac27a0ecSDave Kleikamp b_error = 0; 439ac27a0ecSDave Kleikamp } else { 440ac27a0ecSDave Kleikamp if (buffer) { 441ac27a0ecSDave Kleikamp buffer += i_error; 442ac27a0ecSDave Kleikamp buffer_size -= i_error; 443ac27a0ecSDave Kleikamp } 444617ba13bSMingming Cao b_error = ext4_xattr_block_list(inode, buffer, buffer_size); 445ac27a0ecSDave Kleikamp if (b_error < 0) 446ac27a0ecSDave Kleikamp i_error = 0; 447ac27a0ecSDave Kleikamp } 448617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 449ac27a0ecSDave Kleikamp return i_error + b_error; 450ac27a0ecSDave Kleikamp } 451ac27a0ecSDave Kleikamp 452ac27a0ecSDave Kleikamp /* 453617ba13bSMingming Cao * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is 454ac27a0ecSDave Kleikamp * not set, set it. 455ac27a0ecSDave Kleikamp */ 456617ba13bSMingming Cao static void ext4_xattr_update_super_block(handle_t *handle, 457ac27a0ecSDave Kleikamp struct super_block *sb) 458ac27a0ecSDave Kleikamp { 459617ba13bSMingming Cao if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR)) 460ac27a0ecSDave Kleikamp return; 461ac27a0ecSDave Kleikamp 462ac27a0ecSDave Kleikamp lock_super(sb); 463617ba13bSMingming Cao if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { 464617ba13bSMingming Cao EXT4_SB(sb)->s_es->s_feature_compat |= 465617ba13bSMingming Cao cpu_to_le32(EXT4_FEATURE_COMPAT_EXT_ATTR); 466ac27a0ecSDave Kleikamp sb->s_dirt = 1; 467617ba13bSMingming Cao ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh); 468ac27a0ecSDave Kleikamp } 469ac27a0ecSDave Kleikamp unlock_super(sb); 470ac27a0ecSDave Kleikamp } 471ac27a0ecSDave Kleikamp 472ac27a0ecSDave Kleikamp /* 473ac27a0ecSDave Kleikamp * Release the xattr block BH: If the reference count is > 1, decrement 474ac27a0ecSDave Kleikamp * it; otherwise free the block. 475ac27a0ecSDave Kleikamp */ 476ac27a0ecSDave Kleikamp static void 477617ba13bSMingming Cao ext4_xattr_release_block(handle_t *handle, struct inode *inode, 478ac27a0ecSDave Kleikamp struct buffer_head *bh) 479ac27a0ecSDave Kleikamp { 480ac27a0ecSDave Kleikamp struct mb_cache_entry *ce = NULL; 481ac27a0ecSDave Kleikamp 482617ba13bSMingming Cao ce = mb_cache_entry_get(ext4_xattr_cache, bh->b_bdev, bh->b_blocknr); 483ac27a0ecSDave Kleikamp if (BHDR(bh)->h_refcount == cpu_to_le32(1)) { 484ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=0; freeing"); 485ac27a0ecSDave Kleikamp if (ce) 486ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 487617ba13bSMingming Cao ext4_free_blocks(handle, inode, bh->b_blocknr, 1); 488ac27a0ecSDave Kleikamp get_bh(bh); 489617ba13bSMingming Cao ext4_forget(handle, 1, inode, bh, bh->b_blocknr); 490ac27a0ecSDave Kleikamp } else { 491617ba13bSMingming Cao if (ext4_journal_get_write_access(handle, bh) == 0) { 492ac27a0ecSDave Kleikamp lock_buffer(bh); 493ac27a0ecSDave Kleikamp BHDR(bh)->h_refcount = cpu_to_le32( 494ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount) - 1); 495617ba13bSMingming Cao ext4_journal_dirty_metadata(handle, bh); 496ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 497ac27a0ecSDave Kleikamp handle->h_sync = 1; 498ac27a0ecSDave Kleikamp DQUOT_FREE_BLOCK(inode, 1); 499ac27a0ecSDave Kleikamp unlock_buffer(bh); 500ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=%d; releasing", 501ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount)); 502ac27a0ecSDave Kleikamp } 503ac27a0ecSDave Kleikamp if (ce) 504ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 505ac27a0ecSDave Kleikamp } 506ac27a0ecSDave Kleikamp } 507ac27a0ecSDave Kleikamp 508617ba13bSMingming Cao struct ext4_xattr_info { 509ac27a0ecSDave Kleikamp int name_index; 510ac27a0ecSDave Kleikamp const char *name; 511ac27a0ecSDave Kleikamp const void *value; 512ac27a0ecSDave Kleikamp size_t value_len; 513ac27a0ecSDave Kleikamp }; 514ac27a0ecSDave Kleikamp 515617ba13bSMingming Cao struct ext4_xattr_search { 516617ba13bSMingming Cao struct ext4_xattr_entry *first; 517ac27a0ecSDave Kleikamp void *base; 518ac27a0ecSDave Kleikamp void *end; 519617ba13bSMingming Cao struct ext4_xattr_entry *here; 520ac27a0ecSDave Kleikamp int not_found; 521ac27a0ecSDave Kleikamp }; 522ac27a0ecSDave Kleikamp 523ac27a0ecSDave Kleikamp static int 524617ba13bSMingming Cao ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) 525ac27a0ecSDave Kleikamp { 526617ba13bSMingming Cao struct ext4_xattr_entry *last; 527ac27a0ecSDave Kleikamp size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); 528ac27a0ecSDave Kleikamp 529ac27a0ecSDave Kleikamp /* Compute min_offs and last. */ 530ac27a0ecSDave Kleikamp last = s->first; 531617ba13bSMingming Cao for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 532ac27a0ecSDave Kleikamp if (!last->e_value_block && last->e_value_size) { 533ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(last->e_value_offs); 534ac27a0ecSDave Kleikamp if (offs < min_offs) 535ac27a0ecSDave Kleikamp min_offs = offs; 536ac27a0ecSDave Kleikamp } 537ac27a0ecSDave Kleikamp } 538ac27a0ecSDave Kleikamp free = min_offs - ((void *)last - s->base) - sizeof(__u32); 539ac27a0ecSDave Kleikamp if (!s->not_found) { 540ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 541ac27a0ecSDave Kleikamp size_t size = le32_to_cpu(s->here->e_value_size); 542617ba13bSMingming Cao free += EXT4_XATTR_SIZE(size); 543ac27a0ecSDave Kleikamp } 544617ba13bSMingming Cao free += EXT4_XATTR_LEN(name_len); 545ac27a0ecSDave Kleikamp } 546ac27a0ecSDave Kleikamp if (i->value) { 547617ba13bSMingming Cao if (free < EXT4_XATTR_SIZE(i->value_len) || 548617ba13bSMingming Cao free < EXT4_XATTR_LEN(name_len) + 549617ba13bSMingming Cao EXT4_XATTR_SIZE(i->value_len)) 550ac27a0ecSDave Kleikamp return -ENOSPC; 551ac27a0ecSDave Kleikamp } 552ac27a0ecSDave Kleikamp 553ac27a0ecSDave Kleikamp if (i->value && s->not_found) { 554ac27a0ecSDave Kleikamp /* Insert the new name. */ 555617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 556ac27a0ecSDave Kleikamp size_t rest = (void *)last - (void *)s->here + sizeof(__u32); 557ac27a0ecSDave Kleikamp memmove((void *)s->here + size, s->here, rest); 558ac27a0ecSDave Kleikamp memset(s->here, 0, size); 559ac27a0ecSDave Kleikamp s->here->e_name_index = i->name_index; 560ac27a0ecSDave Kleikamp s->here->e_name_len = name_len; 561ac27a0ecSDave Kleikamp memcpy(s->here->e_name, i->name, name_len); 562ac27a0ecSDave Kleikamp } else { 563ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 564ac27a0ecSDave Kleikamp void *first_val = s->base + min_offs; 565ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(s->here->e_value_offs); 566ac27a0ecSDave Kleikamp void *val = s->base + offs; 567617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE( 568ac27a0ecSDave Kleikamp le32_to_cpu(s->here->e_value_size)); 569ac27a0ecSDave Kleikamp 570617ba13bSMingming Cao if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { 571ac27a0ecSDave Kleikamp /* The old and the new value have the same 572ac27a0ecSDave Kleikamp size. Just replace. */ 573ac27a0ecSDave Kleikamp s->here->e_value_size = 574ac27a0ecSDave Kleikamp cpu_to_le32(i->value_len); 575617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 576617ba13bSMingming Cao EXT4_XATTR_PAD); /* Clear pad bytes. */ 577ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 578ac27a0ecSDave Kleikamp return 0; 579ac27a0ecSDave Kleikamp } 580ac27a0ecSDave Kleikamp 581ac27a0ecSDave Kleikamp /* Remove the old value. */ 582ac27a0ecSDave Kleikamp memmove(first_val + size, first_val, val - first_val); 583ac27a0ecSDave Kleikamp memset(first_val, 0, size); 584ac27a0ecSDave Kleikamp s->here->e_value_size = 0; 585ac27a0ecSDave Kleikamp s->here->e_value_offs = 0; 586ac27a0ecSDave Kleikamp min_offs += size; 587ac27a0ecSDave Kleikamp 588ac27a0ecSDave Kleikamp /* Adjust all value offsets. */ 589ac27a0ecSDave Kleikamp last = s->first; 590ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(last)) { 591ac27a0ecSDave Kleikamp size_t o = le16_to_cpu(last->e_value_offs); 592ac27a0ecSDave Kleikamp if (!last->e_value_block && 593ac27a0ecSDave Kleikamp last->e_value_size && o < offs) 594ac27a0ecSDave Kleikamp last->e_value_offs = 595ac27a0ecSDave Kleikamp cpu_to_le16(o + size); 596617ba13bSMingming Cao last = EXT4_XATTR_NEXT(last); 597ac27a0ecSDave Kleikamp } 598ac27a0ecSDave Kleikamp } 599ac27a0ecSDave Kleikamp if (!i->value) { 600ac27a0ecSDave Kleikamp /* Remove the old name. */ 601617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 602ac27a0ecSDave Kleikamp last = ENTRY((void *)last - size); 603ac27a0ecSDave Kleikamp memmove(s->here, (void *)s->here + size, 604ac27a0ecSDave Kleikamp (void *)last - (void *)s->here + sizeof(__u32)); 605ac27a0ecSDave Kleikamp memset(last, 0, size); 606ac27a0ecSDave Kleikamp } 607ac27a0ecSDave Kleikamp } 608ac27a0ecSDave Kleikamp 609ac27a0ecSDave Kleikamp if (i->value) { 610ac27a0ecSDave Kleikamp /* Insert the new value. */ 611ac27a0ecSDave Kleikamp s->here->e_value_size = cpu_to_le32(i->value_len); 612ac27a0ecSDave Kleikamp if (i->value_len) { 613617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE(i->value_len); 614ac27a0ecSDave Kleikamp void *val = s->base + min_offs - size; 615ac27a0ecSDave Kleikamp s->here->e_value_offs = cpu_to_le16(min_offs - size); 616617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 617617ba13bSMingming Cao EXT4_XATTR_PAD); /* Clear the pad bytes. */ 618ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 619ac27a0ecSDave Kleikamp } 620ac27a0ecSDave Kleikamp } 621ac27a0ecSDave Kleikamp return 0; 622ac27a0ecSDave Kleikamp } 623ac27a0ecSDave Kleikamp 624617ba13bSMingming Cao struct ext4_xattr_block_find { 625617ba13bSMingming Cao struct ext4_xattr_search s; 626ac27a0ecSDave Kleikamp struct buffer_head *bh; 627ac27a0ecSDave Kleikamp }; 628ac27a0ecSDave Kleikamp 629ac27a0ecSDave Kleikamp static int 630617ba13bSMingming Cao ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, 631617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 632ac27a0ecSDave Kleikamp { 633ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 634ac27a0ecSDave Kleikamp int error; 635ac27a0ecSDave Kleikamp 636ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", 637ac27a0ecSDave Kleikamp i->name_index, i->name, i->value, (long)i->value_len); 638ac27a0ecSDave Kleikamp 639617ba13bSMingming Cao if (EXT4_I(inode)->i_file_acl) { 640ac27a0ecSDave Kleikamp /* The inode already has an extended attribute block. */ 641617ba13bSMingming Cao bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); 642ac27a0ecSDave Kleikamp error = -EIO; 643ac27a0ecSDave Kleikamp if (!bs->bh) 644ac27a0ecSDave Kleikamp goto cleanup; 645ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "b_count=%d, refcount=%d", 646ac27a0ecSDave Kleikamp atomic_read(&(bs->bh->b_count)), 647ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bs->bh)->h_refcount)); 648617ba13bSMingming Cao if (ext4_xattr_check_block(bs->bh)) { 649617ba13bSMingming Cao ext4_error(sb, __FUNCTION__, 650*2ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 651617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 652ac27a0ecSDave Kleikamp error = -EIO; 653ac27a0ecSDave Kleikamp goto cleanup; 654ac27a0ecSDave Kleikamp } 655ac27a0ecSDave Kleikamp /* Find the named attribute. */ 656ac27a0ecSDave Kleikamp bs->s.base = BHDR(bs->bh); 657ac27a0ecSDave Kleikamp bs->s.first = BFIRST(bs->bh); 658ac27a0ecSDave Kleikamp bs->s.end = bs->bh->b_data + bs->bh->b_size; 659ac27a0ecSDave Kleikamp bs->s.here = bs->s.first; 660617ba13bSMingming Cao error = ext4_xattr_find_entry(&bs->s.here, i->name_index, 661ac27a0ecSDave Kleikamp i->name, bs->bh->b_size, 1); 662ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 663ac27a0ecSDave Kleikamp goto cleanup; 664ac27a0ecSDave Kleikamp bs->s.not_found = error; 665ac27a0ecSDave Kleikamp } 666ac27a0ecSDave Kleikamp error = 0; 667ac27a0ecSDave Kleikamp 668ac27a0ecSDave Kleikamp cleanup: 669ac27a0ecSDave Kleikamp return error; 670ac27a0ecSDave Kleikamp } 671ac27a0ecSDave Kleikamp 672ac27a0ecSDave Kleikamp static int 673617ba13bSMingming Cao ext4_xattr_block_set(handle_t *handle, struct inode *inode, 674617ba13bSMingming Cao struct ext4_xattr_info *i, 675617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 676ac27a0ecSDave Kleikamp { 677ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 678ac27a0ecSDave Kleikamp struct buffer_head *new_bh = NULL; 679617ba13bSMingming Cao struct ext4_xattr_search *s = &bs->s; 680ac27a0ecSDave Kleikamp struct mb_cache_entry *ce = NULL; 681ac27a0ecSDave Kleikamp int error; 682ac27a0ecSDave Kleikamp 683617ba13bSMingming Cao #define header(x) ((struct ext4_xattr_header *)(x)) 684ac27a0ecSDave Kleikamp 685ac27a0ecSDave Kleikamp if (i->value && i->value_len > sb->s_blocksize) 686ac27a0ecSDave Kleikamp return -ENOSPC; 687ac27a0ecSDave Kleikamp if (s->base) { 688617ba13bSMingming Cao ce = mb_cache_entry_get(ext4_xattr_cache, bs->bh->b_bdev, 689ac27a0ecSDave Kleikamp bs->bh->b_blocknr); 690ac27a0ecSDave Kleikamp if (header(s->base)->h_refcount == cpu_to_le32(1)) { 691ac27a0ecSDave Kleikamp if (ce) { 692ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 693ac27a0ecSDave Kleikamp ce = NULL; 694ac27a0ecSDave Kleikamp } 695ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "modifying in-place"); 696617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, bs->bh); 697ac27a0ecSDave Kleikamp if (error) 698ac27a0ecSDave Kleikamp goto cleanup; 699ac27a0ecSDave Kleikamp lock_buffer(bs->bh); 700617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 701ac27a0ecSDave Kleikamp if (!error) { 702ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 703617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), 704ac27a0ecSDave Kleikamp s->here); 705617ba13bSMingming Cao ext4_xattr_cache_insert(bs->bh); 706ac27a0ecSDave Kleikamp } 707ac27a0ecSDave Kleikamp unlock_buffer(bs->bh); 708ac27a0ecSDave Kleikamp if (error == -EIO) 709ac27a0ecSDave Kleikamp goto bad_block; 710ac27a0ecSDave Kleikamp if (!error) 711617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, 712ac27a0ecSDave Kleikamp bs->bh); 713ac27a0ecSDave Kleikamp if (error) 714ac27a0ecSDave Kleikamp goto cleanup; 715ac27a0ecSDave Kleikamp goto inserted; 716ac27a0ecSDave Kleikamp } else { 717ac27a0ecSDave Kleikamp int offset = (char *)s->here - bs->bh->b_data; 718ac27a0ecSDave Kleikamp 719ac27a0ecSDave Kleikamp if (ce) { 720ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 721ac27a0ecSDave Kleikamp ce = NULL; 722ac27a0ecSDave Kleikamp } 723ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "cloning"); 724ac27a0ecSDave Kleikamp s->base = kmalloc(bs->bh->b_size, GFP_KERNEL); 725ac27a0ecSDave Kleikamp error = -ENOMEM; 726ac27a0ecSDave Kleikamp if (s->base == NULL) 727ac27a0ecSDave Kleikamp goto cleanup; 728ac27a0ecSDave Kleikamp memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); 729ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 730ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 731ac27a0ecSDave Kleikamp s->here = ENTRY(s->base + offset); 732ac27a0ecSDave Kleikamp s->end = s->base + bs->bh->b_size; 733ac27a0ecSDave Kleikamp } 734ac27a0ecSDave Kleikamp } else { 735ac27a0ecSDave Kleikamp /* Allocate a buffer where we construct the new block. */ 736ac27a0ecSDave Kleikamp s->base = kmalloc(sb->s_blocksize, GFP_KERNEL); 737ac27a0ecSDave Kleikamp /* assert(header == s->base) */ 738ac27a0ecSDave Kleikamp error = -ENOMEM; 739ac27a0ecSDave Kleikamp if (s->base == NULL) 740ac27a0ecSDave Kleikamp goto cleanup; 741ac27a0ecSDave Kleikamp memset(s->base, 0, sb->s_blocksize); 742617ba13bSMingming Cao header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 743ac27a0ecSDave Kleikamp header(s->base)->h_blocks = cpu_to_le32(1); 744ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 745ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 746ac27a0ecSDave Kleikamp s->here = ENTRY(header(s->base)+1); 747ac27a0ecSDave Kleikamp s->end = s->base + sb->s_blocksize; 748ac27a0ecSDave Kleikamp } 749ac27a0ecSDave Kleikamp 750617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 751ac27a0ecSDave Kleikamp if (error == -EIO) 752ac27a0ecSDave Kleikamp goto bad_block; 753ac27a0ecSDave Kleikamp if (error) 754ac27a0ecSDave Kleikamp goto cleanup; 755ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 756617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), s->here); 757ac27a0ecSDave Kleikamp 758ac27a0ecSDave Kleikamp inserted: 759ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 760617ba13bSMingming Cao new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); 761ac27a0ecSDave Kleikamp if (new_bh) { 762ac27a0ecSDave Kleikamp /* We found an identical block in the cache. */ 763ac27a0ecSDave Kleikamp if (new_bh == bs->bh) 764ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "keeping"); 765ac27a0ecSDave Kleikamp else { 766ac27a0ecSDave Kleikamp /* The old block is released after updating 767ac27a0ecSDave Kleikamp the inode. */ 768ac27a0ecSDave Kleikamp error = -EDQUOT; 769ac27a0ecSDave Kleikamp if (DQUOT_ALLOC_BLOCK(inode, 1)) 770ac27a0ecSDave Kleikamp goto cleanup; 771617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, 772ac27a0ecSDave Kleikamp new_bh); 773ac27a0ecSDave Kleikamp if (error) 774ac27a0ecSDave Kleikamp goto cleanup_dquot; 775ac27a0ecSDave Kleikamp lock_buffer(new_bh); 776ac27a0ecSDave Kleikamp BHDR(new_bh)->h_refcount = cpu_to_le32(1 + 777ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(new_bh)->h_refcount)); 778ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "reusing; refcount now=%d", 779ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(new_bh)->h_refcount)); 780ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 781617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, 782ac27a0ecSDave Kleikamp new_bh); 783ac27a0ecSDave Kleikamp if (error) 784ac27a0ecSDave Kleikamp goto cleanup_dquot; 785ac27a0ecSDave Kleikamp } 786ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 787ac27a0ecSDave Kleikamp ce = NULL; 788ac27a0ecSDave Kleikamp } else if (bs->bh && s->base == bs->bh->b_data) { 789ac27a0ecSDave Kleikamp /* We were modifying this block in-place. */ 790ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "keeping this block"); 791ac27a0ecSDave Kleikamp new_bh = bs->bh; 792ac27a0ecSDave Kleikamp get_bh(new_bh); 793ac27a0ecSDave Kleikamp } else { 794ac27a0ecSDave Kleikamp /* We need to allocate a new block */ 795617ba13bSMingming Cao ext4_fsblk_t goal = le32_to_cpu( 796617ba13bSMingming Cao EXT4_SB(sb)->s_es->s_first_data_block) + 797617ba13bSMingming Cao (ext4_fsblk_t)EXT4_I(inode)->i_block_group * 798617ba13bSMingming Cao EXT4_BLOCKS_PER_GROUP(sb); 799617ba13bSMingming Cao ext4_fsblk_t block = ext4_new_block(handle, inode, 800ac27a0ecSDave Kleikamp goal, &error); 801ac27a0ecSDave Kleikamp if (error) 802ac27a0ecSDave Kleikamp goto cleanup; 803ac27a0ecSDave Kleikamp ea_idebug(inode, "creating block %d", block); 804ac27a0ecSDave Kleikamp 805ac27a0ecSDave Kleikamp new_bh = sb_getblk(sb, block); 806ac27a0ecSDave Kleikamp if (!new_bh) { 807ac27a0ecSDave Kleikamp getblk_failed: 808617ba13bSMingming Cao ext4_free_blocks(handle, inode, block, 1); 809ac27a0ecSDave Kleikamp error = -EIO; 810ac27a0ecSDave Kleikamp goto cleanup; 811ac27a0ecSDave Kleikamp } 812ac27a0ecSDave Kleikamp lock_buffer(new_bh); 813617ba13bSMingming Cao error = ext4_journal_get_create_access(handle, new_bh); 814ac27a0ecSDave Kleikamp if (error) { 815ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 816ac27a0ecSDave Kleikamp goto getblk_failed; 817ac27a0ecSDave Kleikamp } 818ac27a0ecSDave Kleikamp memcpy(new_bh->b_data, s->base, new_bh->b_size); 819ac27a0ecSDave Kleikamp set_buffer_uptodate(new_bh); 820ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 821617ba13bSMingming Cao ext4_xattr_cache_insert(new_bh); 822617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, new_bh); 823ac27a0ecSDave Kleikamp if (error) 824ac27a0ecSDave Kleikamp goto cleanup; 825ac27a0ecSDave Kleikamp } 826ac27a0ecSDave Kleikamp } 827ac27a0ecSDave Kleikamp 828ac27a0ecSDave Kleikamp /* Update the inode. */ 829617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; 830ac27a0ecSDave Kleikamp 831ac27a0ecSDave Kleikamp /* Drop the previous xattr block. */ 832ac27a0ecSDave Kleikamp if (bs->bh && bs->bh != new_bh) 833617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bs->bh); 834ac27a0ecSDave Kleikamp error = 0; 835ac27a0ecSDave Kleikamp 836ac27a0ecSDave Kleikamp cleanup: 837ac27a0ecSDave Kleikamp if (ce) 838ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 839ac27a0ecSDave Kleikamp brelse(new_bh); 840ac27a0ecSDave Kleikamp if (!(bs->bh && s->base == bs->bh->b_data)) 841ac27a0ecSDave Kleikamp kfree(s->base); 842ac27a0ecSDave Kleikamp 843ac27a0ecSDave Kleikamp return error; 844ac27a0ecSDave Kleikamp 845ac27a0ecSDave Kleikamp cleanup_dquot: 846ac27a0ecSDave Kleikamp DQUOT_FREE_BLOCK(inode, 1); 847ac27a0ecSDave Kleikamp goto cleanup; 848ac27a0ecSDave Kleikamp 849ac27a0ecSDave Kleikamp bad_block: 850617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 851*2ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 852617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 853ac27a0ecSDave Kleikamp goto cleanup; 854ac27a0ecSDave Kleikamp 855ac27a0ecSDave Kleikamp #undef header 856ac27a0ecSDave Kleikamp } 857ac27a0ecSDave Kleikamp 858617ba13bSMingming Cao struct ext4_xattr_ibody_find { 859617ba13bSMingming Cao struct ext4_xattr_search s; 860617ba13bSMingming Cao struct ext4_iloc iloc; 861ac27a0ecSDave Kleikamp }; 862ac27a0ecSDave Kleikamp 863ac27a0ecSDave Kleikamp static int 864617ba13bSMingming Cao ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, 865617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 866ac27a0ecSDave Kleikamp { 867617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 868617ba13bSMingming Cao struct ext4_inode *raw_inode; 869ac27a0ecSDave Kleikamp int error; 870ac27a0ecSDave Kleikamp 871617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 872ac27a0ecSDave Kleikamp return 0; 873617ba13bSMingming Cao raw_inode = ext4_raw_inode(&is->iloc); 874ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 875ac27a0ecSDave Kleikamp is->s.base = is->s.first = IFIRST(header); 876ac27a0ecSDave Kleikamp is->s.here = is->s.first; 877617ba13bSMingming Cao is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 878617ba13bSMingming Cao if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) { 879617ba13bSMingming Cao error = ext4_xattr_check_names(IFIRST(header), is->s.end); 880ac27a0ecSDave Kleikamp if (error) 881ac27a0ecSDave Kleikamp return error; 882ac27a0ecSDave Kleikamp /* Find the named attribute. */ 883617ba13bSMingming Cao error = ext4_xattr_find_entry(&is->s.here, i->name_index, 884ac27a0ecSDave Kleikamp i->name, is->s.end - 885ac27a0ecSDave Kleikamp (void *)is->s.base, 0); 886ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 887ac27a0ecSDave Kleikamp return error; 888ac27a0ecSDave Kleikamp is->s.not_found = error; 889ac27a0ecSDave Kleikamp } 890ac27a0ecSDave Kleikamp return 0; 891ac27a0ecSDave Kleikamp } 892ac27a0ecSDave Kleikamp 893ac27a0ecSDave Kleikamp static int 894617ba13bSMingming Cao ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, 895617ba13bSMingming Cao struct ext4_xattr_info *i, 896617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 897ac27a0ecSDave Kleikamp { 898617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 899617ba13bSMingming Cao struct ext4_xattr_search *s = &is->s; 900ac27a0ecSDave Kleikamp int error; 901ac27a0ecSDave Kleikamp 902617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 903ac27a0ecSDave Kleikamp return -ENOSPC; 904617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 905ac27a0ecSDave Kleikamp if (error) 906ac27a0ecSDave Kleikamp return error; 907617ba13bSMingming Cao header = IHDR(inode, ext4_raw_inode(&is->iloc)); 908ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 909617ba13bSMingming Cao header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 910617ba13bSMingming Cao EXT4_I(inode)->i_state |= EXT4_STATE_XATTR; 911ac27a0ecSDave Kleikamp } else { 912ac27a0ecSDave Kleikamp header->h_magic = cpu_to_le32(0); 913617ba13bSMingming Cao EXT4_I(inode)->i_state &= ~EXT4_STATE_XATTR; 914ac27a0ecSDave Kleikamp } 915ac27a0ecSDave Kleikamp return 0; 916ac27a0ecSDave Kleikamp } 917ac27a0ecSDave Kleikamp 918ac27a0ecSDave Kleikamp /* 919617ba13bSMingming Cao * ext4_xattr_set_handle() 920ac27a0ecSDave Kleikamp * 921ac27a0ecSDave Kleikamp * Create, replace or remove an extended attribute for this inode. Buffer 922ac27a0ecSDave Kleikamp * is NULL to remove an existing extended attribute, and non-NULL to 923ac27a0ecSDave Kleikamp * either replace an existing extended attribute, or create a new extended 924ac27a0ecSDave Kleikamp * attribute. The flags XATTR_REPLACE and XATTR_CREATE 925ac27a0ecSDave Kleikamp * specify that an extended attribute must exist and must not exist 926ac27a0ecSDave Kleikamp * previous to the call, respectively. 927ac27a0ecSDave Kleikamp * 928ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 929ac27a0ecSDave Kleikamp */ 930ac27a0ecSDave Kleikamp int 931617ba13bSMingming Cao ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, 932ac27a0ecSDave Kleikamp const char *name, const void *value, size_t value_len, 933ac27a0ecSDave Kleikamp int flags) 934ac27a0ecSDave Kleikamp { 935617ba13bSMingming Cao struct ext4_xattr_info i = { 936ac27a0ecSDave Kleikamp .name_index = name_index, 937ac27a0ecSDave Kleikamp .name = name, 938ac27a0ecSDave Kleikamp .value = value, 939ac27a0ecSDave Kleikamp .value_len = value_len, 940ac27a0ecSDave Kleikamp 941ac27a0ecSDave Kleikamp }; 942617ba13bSMingming Cao struct ext4_xattr_ibody_find is = { 943ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 944ac27a0ecSDave Kleikamp }; 945617ba13bSMingming Cao struct ext4_xattr_block_find bs = { 946ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 947ac27a0ecSDave Kleikamp }; 948ac27a0ecSDave Kleikamp int error; 949ac27a0ecSDave Kleikamp 950ac27a0ecSDave Kleikamp if (!name) 951ac27a0ecSDave Kleikamp return -EINVAL; 952ac27a0ecSDave Kleikamp if (strlen(name) > 255) 953ac27a0ecSDave Kleikamp return -ERANGE; 954617ba13bSMingming Cao down_write(&EXT4_I(inode)->xattr_sem); 955617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &is.iloc); 956ac27a0ecSDave Kleikamp if (error) 957ac27a0ecSDave Kleikamp goto cleanup; 958ac27a0ecSDave Kleikamp 959617ba13bSMingming Cao if (EXT4_I(inode)->i_state & EXT4_STATE_NEW) { 960617ba13bSMingming Cao struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); 961617ba13bSMingming Cao memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); 962617ba13bSMingming Cao EXT4_I(inode)->i_state &= ~EXT4_STATE_NEW; 963ac27a0ecSDave Kleikamp } 964ac27a0ecSDave Kleikamp 965617ba13bSMingming Cao error = ext4_xattr_ibody_find(inode, &i, &is); 966ac27a0ecSDave Kleikamp if (error) 967ac27a0ecSDave Kleikamp goto cleanup; 968ac27a0ecSDave Kleikamp if (is.s.not_found) 969617ba13bSMingming Cao error = ext4_xattr_block_find(inode, &i, &bs); 970ac27a0ecSDave Kleikamp if (error) 971ac27a0ecSDave Kleikamp goto cleanup; 972ac27a0ecSDave Kleikamp if (is.s.not_found && bs.s.not_found) { 973ac27a0ecSDave Kleikamp error = -ENODATA; 974ac27a0ecSDave Kleikamp if (flags & XATTR_REPLACE) 975ac27a0ecSDave Kleikamp goto cleanup; 976ac27a0ecSDave Kleikamp error = 0; 977ac27a0ecSDave Kleikamp if (!value) 978ac27a0ecSDave Kleikamp goto cleanup; 979ac27a0ecSDave Kleikamp } else { 980ac27a0ecSDave Kleikamp error = -EEXIST; 981ac27a0ecSDave Kleikamp if (flags & XATTR_CREATE) 982ac27a0ecSDave Kleikamp goto cleanup; 983ac27a0ecSDave Kleikamp } 984617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, is.iloc.bh); 985ac27a0ecSDave Kleikamp if (error) 986ac27a0ecSDave Kleikamp goto cleanup; 987ac27a0ecSDave Kleikamp if (!value) { 988ac27a0ecSDave Kleikamp if (!is.s.not_found) 989617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 990ac27a0ecSDave Kleikamp else if (!bs.s.not_found) 991617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 992ac27a0ecSDave Kleikamp } else { 993617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 994ac27a0ecSDave Kleikamp if (!error && !bs.s.not_found) { 995ac27a0ecSDave Kleikamp i.value = NULL; 996617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 997ac27a0ecSDave Kleikamp } else if (error == -ENOSPC) { 998617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 999ac27a0ecSDave Kleikamp if (error) 1000ac27a0ecSDave Kleikamp goto cleanup; 1001ac27a0ecSDave Kleikamp if (!is.s.not_found) { 1002ac27a0ecSDave Kleikamp i.value = NULL; 1003617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, 1004ac27a0ecSDave Kleikamp &is); 1005ac27a0ecSDave Kleikamp } 1006ac27a0ecSDave Kleikamp } 1007ac27a0ecSDave Kleikamp } 1008ac27a0ecSDave Kleikamp if (!error) { 1009617ba13bSMingming Cao ext4_xattr_update_super_block(handle, inode->i_sb); 1010ac27a0ecSDave Kleikamp inode->i_ctime = CURRENT_TIME_SEC; 1011617ba13bSMingming Cao error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); 1012ac27a0ecSDave Kleikamp /* 1013617ba13bSMingming Cao * The bh is consumed by ext4_mark_iloc_dirty, even with 1014ac27a0ecSDave Kleikamp * error != 0. 1015ac27a0ecSDave Kleikamp */ 1016ac27a0ecSDave Kleikamp is.iloc.bh = NULL; 1017ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 1018ac27a0ecSDave Kleikamp handle->h_sync = 1; 1019ac27a0ecSDave Kleikamp } 1020ac27a0ecSDave Kleikamp 1021ac27a0ecSDave Kleikamp cleanup: 1022ac27a0ecSDave Kleikamp brelse(is.iloc.bh); 1023ac27a0ecSDave Kleikamp brelse(bs.bh); 1024617ba13bSMingming Cao up_write(&EXT4_I(inode)->xattr_sem); 1025ac27a0ecSDave Kleikamp return error; 1026ac27a0ecSDave Kleikamp } 1027ac27a0ecSDave Kleikamp 1028ac27a0ecSDave Kleikamp /* 1029617ba13bSMingming Cao * ext4_xattr_set() 1030ac27a0ecSDave Kleikamp * 1031617ba13bSMingming Cao * Like ext4_xattr_set_handle, but start from an inode. This extended 1032ac27a0ecSDave Kleikamp * attribute modification is a filesystem transaction by itself. 1033ac27a0ecSDave Kleikamp * 1034ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1035ac27a0ecSDave Kleikamp */ 1036ac27a0ecSDave Kleikamp int 1037617ba13bSMingming Cao ext4_xattr_set(struct inode *inode, int name_index, const char *name, 1038ac27a0ecSDave Kleikamp const void *value, size_t value_len, int flags) 1039ac27a0ecSDave Kleikamp { 1040ac27a0ecSDave Kleikamp handle_t *handle; 1041ac27a0ecSDave Kleikamp int error, retries = 0; 1042ac27a0ecSDave Kleikamp 1043ac27a0ecSDave Kleikamp retry: 1044617ba13bSMingming Cao handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb)); 1045ac27a0ecSDave Kleikamp if (IS_ERR(handle)) { 1046ac27a0ecSDave Kleikamp error = PTR_ERR(handle); 1047ac27a0ecSDave Kleikamp } else { 1048ac27a0ecSDave Kleikamp int error2; 1049ac27a0ecSDave Kleikamp 1050617ba13bSMingming Cao error = ext4_xattr_set_handle(handle, inode, name_index, name, 1051ac27a0ecSDave Kleikamp value, value_len, flags); 1052617ba13bSMingming Cao error2 = ext4_journal_stop(handle); 1053ac27a0ecSDave Kleikamp if (error == -ENOSPC && 1054617ba13bSMingming Cao ext4_should_retry_alloc(inode->i_sb, &retries)) 1055ac27a0ecSDave Kleikamp goto retry; 1056ac27a0ecSDave Kleikamp if (error == 0) 1057ac27a0ecSDave Kleikamp error = error2; 1058ac27a0ecSDave Kleikamp } 1059ac27a0ecSDave Kleikamp 1060ac27a0ecSDave Kleikamp return error; 1061ac27a0ecSDave Kleikamp } 1062ac27a0ecSDave Kleikamp 1063ac27a0ecSDave Kleikamp /* 1064617ba13bSMingming Cao * ext4_xattr_delete_inode() 1065ac27a0ecSDave Kleikamp * 1066ac27a0ecSDave Kleikamp * Free extended attribute resources associated with this inode. This 1067ac27a0ecSDave Kleikamp * is called immediately before an inode is freed. We have exclusive 1068ac27a0ecSDave Kleikamp * access to the inode. 1069ac27a0ecSDave Kleikamp */ 1070ac27a0ecSDave Kleikamp void 1071617ba13bSMingming Cao ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) 1072ac27a0ecSDave Kleikamp { 1073ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 1074ac27a0ecSDave Kleikamp 1075617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 1076ac27a0ecSDave Kleikamp goto cleanup; 1077617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 1078ac27a0ecSDave Kleikamp if (!bh) { 1079617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 1080*2ae02107SMingming Cao "inode %lu: block %llu read error", inode->i_ino, 1081617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 1082ac27a0ecSDave Kleikamp goto cleanup; 1083ac27a0ecSDave Kleikamp } 1084617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 1085ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) { 1086617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 1087*2ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 1088617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 1089ac27a0ecSDave Kleikamp goto cleanup; 1090ac27a0ecSDave Kleikamp } 1091617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bh); 1092617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = 0; 1093ac27a0ecSDave Kleikamp 1094ac27a0ecSDave Kleikamp cleanup: 1095ac27a0ecSDave Kleikamp brelse(bh); 1096ac27a0ecSDave Kleikamp } 1097ac27a0ecSDave Kleikamp 1098ac27a0ecSDave Kleikamp /* 1099617ba13bSMingming Cao * ext4_xattr_put_super() 1100ac27a0ecSDave Kleikamp * 1101ac27a0ecSDave Kleikamp * This is called when a file system is unmounted. 1102ac27a0ecSDave Kleikamp */ 1103ac27a0ecSDave Kleikamp void 1104617ba13bSMingming Cao ext4_xattr_put_super(struct super_block *sb) 1105ac27a0ecSDave Kleikamp { 1106ac27a0ecSDave Kleikamp mb_cache_shrink(sb->s_bdev); 1107ac27a0ecSDave Kleikamp } 1108ac27a0ecSDave Kleikamp 1109ac27a0ecSDave Kleikamp /* 1110617ba13bSMingming Cao * ext4_xattr_cache_insert() 1111ac27a0ecSDave Kleikamp * 1112ac27a0ecSDave Kleikamp * Create a new entry in the extended attribute cache, and insert 1113ac27a0ecSDave Kleikamp * it unless such an entry is already in the cache. 1114ac27a0ecSDave Kleikamp * 1115ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1116ac27a0ecSDave Kleikamp */ 1117ac27a0ecSDave Kleikamp static void 1118617ba13bSMingming Cao ext4_xattr_cache_insert(struct buffer_head *bh) 1119ac27a0ecSDave Kleikamp { 1120ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(BHDR(bh)->h_hash); 1121ac27a0ecSDave Kleikamp struct mb_cache_entry *ce; 1122ac27a0ecSDave Kleikamp int error; 1123ac27a0ecSDave Kleikamp 1124617ba13bSMingming Cao ce = mb_cache_entry_alloc(ext4_xattr_cache); 1125ac27a0ecSDave Kleikamp if (!ce) { 1126ac27a0ecSDave Kleikamp ea_bdebug(bh, "out of memory"); 1127ac27a0ecSDave Kleikamp return; 1128ac27a0ecSDave Kleikamp } 1129ac27a0ecSDave Kleikamp error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash); 1130ac27a0ecSDave Kleikamp if (error) { 1131ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 1132ac27a0ecSDave Kleikamp if (error == -EBUSY) { 1133ac27a0ecSDave Kleikamp ea_bdebug(bh, "already in cache"); 1134ac27a0ecSDave Kleikamp error = 0; 1135ac27a0ecSDave Kleikamp } 1136ac27a0ecSDave Kleikamp } else { 1137ac27a0ecSDave Kleikamp ea_bdebug(bh, "inserting [%x]", (int)hash); 1138ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 1139ac27a0ecSDave Kleikamp } 1140ac27a0ecSDave Kleikamp } 1141ac27a0ecSDave Kleikamp 1142ac27a0ecSDave Kleikamp /* 1143617ba13bSMingming Cao * ext4_xattr_cmp() 1144ac27a0ecSDave Kleikamp * 1145ac27a0ecSDave Kleikamp * Compare two extended attribute blocks for equality. 1146ac27a0ecSDave Kleikamp * 1147ac27a0ecSDave Kleikamp * Returns 0 if the blocks are equal, 1 if they differ, and 1148ac27a0ecSDave Kleikamp * a negative error number on errors. 1149ac27a0ecSDave Kleikamp */ 1150ac27a0ecSDave Kleikamp static int 1151617ba13bSMingming Cao ext4_xattr_cmp(struct ext4_xattr_header *header1, 1152617ba13bSMingming Cao struct ext4_xattr_header *header2) 1153ac27a0ecSDave Kleikamp { 1154617ba13bSMingming Cao struct ext4_xattr_entry *entry1, *entry2; 1155ac27a0ecSDave Kleikamp 1156ac27a0ecSDave Kleikamp entry1 = ENTRY(header1+1); 1157ac27a0ecSDave Kleikamp entry2 = ENTRY(header2+1); 1158ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry1)) { 1159ac27a0ecSDave Kleikamp if (IS_LAST_ENTRY(entry2)) 1160ac27a0ecSDave Kleikamp return 1; 1161ac27a0ecSDave Kleikamp if (entry1->e_hash != entry2->e_hash || 1162ac27a0ecSDave Kleikamp entry1->e_name_index != entry2->e_name_index || 1163ac27a0ecSDave Kleikamp entry1->e_name_len != entry2->e_name_len || 1164ac27a0ecSDave Kleikamp entry1->e_value_size != entry2->e_value_size || 1165ac27a0ecSDave Kleikamp memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) 1166ac27a0ecSDave Kleikamp return 1; 1167ac27a0ecSDave Kleikamp if (entry1->e_value_block != 0 || entry2->e_value_block != 0) 1168ac27a0ecSDave Kleikamp return -EIO; 1169ac27a0ecSDave Kleikamp if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), 1170ac27a0ecSDave Kleikamp (char *)header2 + le16_to_cpu(entry2->e_value_offs), 1171ac27a0ecSDave Kleikamp le32_to_cpu(entry1->e_value_size))) 1172ac27a0ecSDave Kleikamp return 1; 1173ac27a0ecSDave Kleikamp 1174617ba13bSMingming Cao entry1 = EXT4_XATTR_NEXT(entry1); 1175617ba13bSMingming Cao entry2 = EXT4_XATTR_NEXT(entry2); 1176ac27a0ecSDave Kleikamp } 1177ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(entry2)) 1178ac27a0ecSDave Kleikamp return 1; 1179ac27a0ecSDave Kleikamp return 0; 1180ac27a0ecSDave Kleikamp } 1181ac27a0ecSDave Kleikamp 1182ac27a0ecSDave Kleikamp /* 1183617ba13bSMingming Cao * ext4_xattr_cache_find() 1184ac27a0ecSDave Kleikamp * 1185ac27a0ecSDave Kleikamp * Find an identical extended attribute block. 1186ac27a0ecSDave Kleikamp * 1187ac27a0ecSDave Kleikamp * Returns a pointer to the block found, or NULL if such a block was 1188ac27a0ecSDave Kleikamp * not found or an error occurred. 1189ac27a0ecSDave Kleikamp */ 1190ac27a0ecSDave Kleikamp static struct buffer_head * 1191617ba13bSMingming Cao ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, 1192ac27a0ecSDave Kleikamp struct mb_cache_entry **pce) 1193ac27a0ecSDave Kleikamp { 1194ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(header->h_hash); 1195ac27a0ecSDave Kleikamp struct mb_cache_entry *ce; 1196ac27a0ecSDave Kleikamp 1197ac27a0ecSDave Kleikamp if (!header->h_hash) 1198ac27a0ecSDave Kleikamp return NULL; /* never share */ 1199ac27a0ecSDave Kleikamp ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); 1200ac27a0ecSDave Kleikamp again: 1201617ba13bSMingming Cao ce = mb_cache_entry_find_first(ext4_xattr_cache, 0, 1202ac27a0ecSDave Kleikamp inode->i_sb->s_bdev, hash); 1203ac27a0ecSDave Kleikamp while (ce) { 1204ac27a0ecSDave Kleikamp struct buffer_head *bh; 1205ac27a0ecSDave Kleikamp 1206ac27a0ecSDave Kleikamp if (IS_ERR(ce)) { 1207ac27a0ecSDave Kleikamp if (PTR_ERR(ce) == -EAGAIN) 1208ac27a0ecSDave Kleikamp goto again; 1209ac27a0ecSDave Kleikamp break; 1210ac27a0ecSDave Kleikamp } 1211ac27a0ecSDave Kleikamp bh = sb_bread(inode->i_sb, ce->e_block); 1212ac27a0ecSDave Kleikamp if (!bh) { 1213617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 1214ac27a0ecSDave Kleikamp "inode %lu: block %lu read error", 1215ac27a0ecSDave Kleikamp inode->i_ino, (unsigned long) ce->e_block); 1216ac27a0ecSDave Kleikamp } else if (le32_to_cpu(BHDR(bh)->h_refcount) >= 1217617ba13bSMingming Cao EXT4_XATTR_REFCOUNT_MAX) { 1218ac27a0ecSDave Kleikamp ea_idebug(inode, "block %lu refcount %d>=%d", 1219ac27a0ecSDave Kleikamp (unsigned long) ce->e_block, 1220ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount), 1221617ba13bSMingming Cao EXT4_XATTR_REFCOUNT_MAX); 1222617ba13bSMingming Cao } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { 1223ac27a0ecSDave Kleikamp *pce = ce; 1224ac27a0ecSDave Kleikamp return bh; 1225ac27a0ecSDave Kleikamp } 1226ac27a0ecSDave Kleikamp brelse(bh); 1227ac27a0ecSDave Kleikamp ce = mb_cache_entry_find_next(ce, 0, inode->i_sb->s_bdev, hash); 1228ac27a0ecSDave Kleikamp } 1229ac27a0ecSDave Kleikamp return NULL; 1230ac27a0ecSDave Kleikamp } 1231ac27a0ecSDave Kleikamp 1232ac27a0ecSDave Kleikamp #define NAME_HASH_SHIFT 5 1233ac27a0ecSDave Kleikamp #define VALUE_HASH_SHIFT 16 1234ac27a0ecSDave Kleikamp 1235ac27a0ecSDave Kleikamp /* 1236617ba13bSMingming Cao * ext4_xattr_hash_entry() 1237ac27a0ecSDave Kleikamp * 1238ac27a0ecSDave Kleikamp * Compute the hash of an extended attribute. 1239ac27a0ecSDave Kleikamp */ 1240617ba13bSMingming Cao static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, 1241617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1242ac27a0ecSDave Kleikamp { 1243ac27a0ecSDave Kleikamp __u32 hash = 0; 1244ac27a0ecSDave Kleikamp char *name = entry->e_name; 1245ac27a0ecSDave Kleikamp int n; 1246ac27a0ecSDave Kleikamp 1247ac27a0ecSDave Kleikamp for (n=0; n < entry->e_name_len; n++) { 1248ac27a0ecSDave Kleikamp hash = (hash << NAME_HASH_SHIFT) ^ 1249ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ 1250ac27a0ecSDave Kleikamp *name++; 1251ac27a0ecSDave Kleikamp } 1252ac27a0ecSDave Kleikamp 1253ac27a0ecSDave Kleikamp if (entry->e_value_block == 0 && entry->e_value_size != 0) { 1254ac27a0ecSDave Kleikamp __le32 *value = (__le32 *)((char *)header + 1255ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs)); 1256ac27a0ecSDave Kleikamp for (n = (le32_to_cpu(entry->e_value_size) + 1257617ba13bSMingming Cao EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { 1258ac27a0ecSDave Kleikamp hash = (hash << VALUE_HASH_SHIFT) ^ 1259ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ 1260ac27a0ecSDave Kleikamp le32_to_cpu(*value++); 1261ac27a0ecSDave Kleikamp } 1262ac27a0ecSDave Kleikamp } 1263ac27a0ecSDave Kleikamp entry->e_hash = cpu_to_le32(hash); 1264ac27a0ecSDave Kleikamp } 1265ac27a0ecSDave Kleikamp 1266ac27a0ecSDave Kleikamp #undef NAME_HASH_SHIFT 1267ac27a0ecSDave Kleikamp #undef VALUE_HASH_SHIFT 1268ac27a0ecSDave Kleikamp 1269ac27a0ecSDave Kleikamp #define BLOCK_HASH_SHIFT 16 1270ac27a0ecSDave Kleikamp 1271ac27a0ecSDave Kleikamp /* 1272617ba13bSMingming Cao * ext4_xattr_rehash() 1273ac27a0ecSDave Kleikamp * 1274ac27a0ecSDave Kleikamp * Re-compute the extended attribute hash value after an entry has changed. 1275ac27a0ecSDave Kleikamp */ 1276617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *header, 1277617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1278ac27a0ecSDave Kleikamp { 1279617ba13bSMingming Cao struct ext4_xattr_entry *here; 1280ac27a0ecSDave Kleikamp __u32 hash = 0; 1281ac27a0ecSDave Kleikamp 1282617ba13bSMingming Cao ext4_xattr_hash_entry(header, entry); 1283ac27a0ecSDave Kleikamp here = ENTRY(header+1); 1284ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(here)) { 1285ac27a0ecSDave Kleikamp if (!here->e_hash) { 1286ac27a0ecSDave Kleikamp /* Block is not shared if an entry's hash value == 0 */ 1287ac27a0ecSDave Kleikamp hash = 0; 1288ac27a0ecSDave Kleikamp break; 1289ac27a0ecSDave Kleikamp } 1290ac27a0ecSDave Kleikamp hash = (hash << BLOCK_HASH_SHIFT) ^ 1291ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ 1292ac27a0ecSDave Kleikamp le32_to_cpu(here->e_hash); 1293617ba13bSMingming Cao here = EXT4_XATTR_NEXT(here); 1294ac27a0ecSDave Kleikamp } 1295ac27a0ecSDave Kleikamp header->h_hash = cpu_to_le32(hash); 1296ac27a0ecSDave Kleikamp } 1297ac27a0ecSDave Kleikamp 1298ac27a0ecSDave Kleikamp #undef BLOCK_HASH_SHIFT 1299ac27a0ecSDave Kleikamp 1300ac27a0ecSDave Kleikamp int __init 1301617ba13bSMingming Cao init_ext4_xattr(void) 1302ac27a0ecSDave Kleikamp { 1303617ba13bSMingming Cao ext4_xattr_cache = mb_cache_create("ext4_xattr", NULL, 1304ac27a0ecSDave Kleikamp sizeof(struct mb_cache_entry) + 1305ac27a0ecSDave Kleikamp sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]), 1, 6); 1306617ba13bSMingming Cao if (!ext4_xattr_cache) 1307ac27a0ecSDave Kleikamp return -ENOMEM; 1308ac27a0ecSDave Kleikamp return 0; 1309ac27a0ecSDave Kleikamp } 1310ac27a0ecSDave Kleikamp 1311ac27a0ecSDave Kleikamp void 1312617ba13bSMingming Cao exit_ext4_xattr(void) 1313ac27a0ecSDave Kleikamp { 1314617ba13bSMingming Cao if (ext4_xattr_cache) 1315617ba13bSMingming Cao mb_cache_destroy(ext4_xattr_cache); 1316617ba13bSMingming Cao ext4_xattr_cache = NULL; 1317ac27a0ecSDave Kleikamp } 1318