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 69617ba13bSMingming Cao #ifdef EXT4_XATTR_DEBUG 70ac27a0ecSDave Kleikamp # define ea_idebug(inode, f...) do { \ 71ac27a0ecSDave Kleikamp printk(KERN_DEBUG "inode %s:%lu: ", \ 72ac27a0ecSDave Kleikamp inode->i_sb->s_id, inode->i_ino); \ 73ac27a0ecSDave Kleikamp printk(f); \ 74ac27a0ecSDave Kleikamp printk("\n"); \ 75ac27a0ecSDave Kleikamp } while (0) 76ac27a0ecSDave Kleikamp # define ea_bdebug(bh, f...) do { \ 77ac27a0ecSDave Kleikamp char b[BDEVNAME_SIZE]; \ 78ac27a0ecSDave Kleikamp printk(KERN_DEBUG "block %s:%lu: ", \ 79ac27a0ecSDave Kleikamp bdevname(bh->b_bdev, b), \ 80ac27a0ecSDave Kleikamp (unsigned long) bh->b_blocknr); \ 81ac27a0ecSDave Kleikamp printk(f); \ 82ac27a0ecSDave Kleikamp printk("\n"); \ 83ac27a0ecSDave Kleikamp } while (0) 84ac27a0ecSDave Kleikamp #else 85ac27a0ecSDave Kleikamp # define ea_idebug(f...) 86ac27a0ecSDave Kleikamp # define ea_bdebug(f...) 87ac27a0ecSDave Kleikamp #endif 88ac27a0ecSDave Kleikamp 89617ba13bSMingming Cao static void ext4_xattr_cache_insert(struct buffer_head *); 90617ba13bSMingming Cao static struct buffer_head *ext4_xattr_cache_find(struct inode *, 91617ba13bSMingming Cao struct ext4_xattr_header *, 92ac27a0ecSDave Kleikamp struct mb_cache_entry **); 93617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *, 94617ba13bSMingming Cao struct ext4_xattr_entry *); 95ac27a0ecSDave Kleikamp 96617ba13bSMingming Cao static struct mb_cache *ext4_xattr_cache; 97ac27a0ecSDave Kleikamp 98617ba13bSMingming Cao static struct xattr_handler *ext4_xattr_handler_map[] = { 99617ba13bSMingming Cao [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, 100617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL 101617ba13bSMingming Cao [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext4_xattr_acl_access_handler, 102617ba13bSMingming Cao [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext4_xattr_acl_default_handler, 103ac27a0ecSDave Kleikamp #endif 104617ba13bSMingming Cao [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, 105617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_SECURITY 106617ba13bSMingming Cao [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, 107ac27a0ecSDave Kleikamp #endif 108ac27a0ecSDave Kleikamp }; 109ac27a0ecSDave Kleikamp 110617ba13bSMingming Cao struct xattr_handler *ext4_xattr_handlers[] = { 111617ba13bSMingming Cao &ext4_xattr_user_handler, 112617ba13bSMingming Cao &ext4_xattr_trusted_handler, 113617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL 114617ba13bSMingming Cao &ext4_xattr_acl_access_handler, 115617ba13bSMingming Cao &ext4_xattr_acl_default_handler, 116ac27a0ecSDave Kleikamp #endif 117617ba13bSMingming Cao #ifdef CONFIG_EXT4DEV_FS_SECURITY 118617ba13bSMingming Cao &ext4_xattr_security_handler, 119ac27a0ecSDave Kleikamp #endif 120ac27a0ecSDave Kleikamp NULL 121ac27a0ecSDave Kleikamp }; 122ac27a0ecSDave Kleikamp 123ac27a0ecSDave Kleikamp static inline struct xattr_handler * 124617ba13bSMingming Cao ext4_xattr_handler(int name_index) 125ac27a0ecSDave Kleikamp { 126ac27a0ecSDave Kleikamp struct xattr_handler *handler = NULL; 127ac27a0ecSDave Kleikamp 128617ba13bSMingming Cao if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) 129617ba13bSMingming Cao handler = ext4_xattr_handler_map[name_index]; 130ac27a0ecSDave Kleikamp return handler; 131ac27a0ecSDave Kleikamp } 132ac27a0ecSDave Kleikamp 133ac27a0ecSDave Kleikamp /* 134ac27a0ecSDave Kleikamp * Inode operation listxattr() 135ac27a0ecSDave Kleikamp * 136ac27a0ecSDave Kleikamp * dentry->d_inode->i_mutex: don't care 137ac27a0ecSDave Kleikamp */ 138ac27a0ecSDave Kleikamp ssize_t 139617ba13bSMingming Cao ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) 140ac27a0ecSDave Kleikamp { 141617ba13bSMingming Cao return ext4_xattr_list(dentry->d_inode, buffer, size); 142ac27a0ecSDave Kleikamp } 143ac27a0ecSDave Kleikamp 144ac27a0ecSDave Kleikamp static int 145617ba13bSMingming Cao ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end) 146ac27a0ecSDave Kleikamp { 147ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry)) { 148617ba13bSMingming Cao struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(entry); 149ac27a0ecSDave Kleikamp if ((void *)next >= end) 150ac27a0ecSDave Kleikamp return -EIO; 151ac27a0ecSDave Kleikamp entry = next; 152ac27a0ecSDave Kleikamp } 153ac27a0ecSDave Kleikamp return 0; 154ac27a0ecSDave Kleikamp } 155ac27a0ecSDave Kleikamp 156ac27a0ecSDave Kleikamp static inline int 157617ba13bSMingming Cao ext4_xattr_check_block(struct buffer_head *bh) 158ac27a0ecSDave Kleikamp { 159ac27a0ecSDave Kleikamp int error; 160ac27a0ecSDave Kleikamp 161617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 162ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) 163ac27a0ecSDave Kleikamp return -EIO; 164617ba13bSMingming Cao error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size); 165ac27a0ecSDave Kleikamp return error; 166ac27a0ecSDave Kleikamp } 167ac27a0ecSDave Kleikamp 168ac27a0ecSDave Kleikamp static inline int 169617ba13bSMingming Cao ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) 170ac27a0ecSDave Kleikamp { 171ac27a0ecSDave Kleikamp size_t value_size = le32_to_cpu(entry->e_value_size); 172ac27a0ecSDave Kleikamp 173ac27a0ecSDave Kleikamp if (entry->e_value_block != 0 || value_size > size || 174ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs) + value_size > size) 175ac27a0ecSDave Kleikamp return -EIO; 176ac27a0ecSDave Kleikamp return 0; 177ac27a0ecSDave Kleikamp } 178ac27a0ecSDave Kleikamp 179ac27a0ecSDave Kleikamp static int 180617ba13bSMingming Cao ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, 181ac27a0ecSDave Kleikamp const char *name, size_t size, int sorted) 182ac27a0ecSDave Kleikamp { 183617ba13bSMingming Cao struct ext4_xattr_entry *entry; 184ac27a0ecSDave Kleikamp size_t name_len; 185ac27a0ecSDave Kleikamp int cmp = 1; 186ac27a0ecSDave Kleikamp 187ac27a0ecSDave Kleikamp if (name == NULL) 188ac27a0ecSDave Kleikamp return -EINVAL; 189ac27a0ecSDave Kleikamp name_len = strlen(name); 190ac27a0ecSDave Kleikamp entry = *pentry; 191617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 192ac27a0ecSDave Kleikamp cmp = name_index - entry->e_name_index; 193ac27a0ecSDave Kleikamp if (!cmp) 194ac27a0ecSDave Kleikamp cmp = name_len - entry->e_name_len; 195ac27a0ecSDave Kleikamp if (!cmp) 196ac27a0ecSDave Kleikamp cmp = memcmp(name, entry->e_name, name_len); 197ac27a0ecSDave Kleikamp if (cmp <= 0 && (sorted || cmp == 0)) 198ac27a0ecSDave Kleikamp break; 199ac27a0ecSDave Kleikamp } 200ac27a0ecSDave Kleikamp *pentry = entry; 201617ba13bSMingming Cao if (!cmp && ext4_xattr_check_entry(entry, size)) 202ac27a0ecSDave Kleikamp return -EIO; 203ac27a0ecSDave Kleikamp return cmp ? -ENODATA : 0; 204ac27a0ecSDave Kleikamp } 205ac27a0ecSDave Kleikamp 206ac27a0ecSDave Kleikamp static int 207617ba13bSMingming Cao ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, 208ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 209ac27a0ecSDave Kleikamp { 210ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 211617ba13bSMingming Cao struct ext4_xattr_entry *entry; 212ac27a0ecSDave Kleikamp size_t size; 213ac27a0ecSDave Kleikamp int error; 214ac27a0ecSDave Kleikamp 215ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", 216ac27a0ecSDave Kleikamp name_index, name, buffer, (long)buffer_size); 217ac27a0ecSDave Kleikamp 218ac27a0ecSDave Kleikamp error = -ENODATA; 219617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 220ac27a0ecSDave Kleikamp goto cleanup; 221617ba13bSMingming Cao ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl); 222617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 223ac27a0ecSDave Kleikamp if (!bh) 224ac27a0ecSDave Kleikamp goto cleanup; 225ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 226ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 227617ba13bSMingming Cao if (ext4_xattr_check_block(bh)) { 228617ba13bSMingming Cao bad_block: ext4_error(inode->i_sb, __FUNCTION__, 2292ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 230617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 231ac27a0ecSDave Kleikamp error = -EIO; 232ac27a0ecSDave Kleikamp goto cleanup; 233ac27a0ecSDave Kleikamp } 234617ba13bSMingming Cao ext4_xattr_cache_insert(bh); 235ac27a0ecSDave Kleikamp entry = BFIRST(bh); 236617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); 237ac27a0ecSDave Kleikamp if (error == -EIO) 238ac27a0ecSDave Kleikamp goto bad_block; 239ac27a0ecSDave Kleikamp if (error) 240ac27a0ecSDave Kleikamp goto cleanup; 241ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 242ac27a0ecSDave Kleikamp if (buffer) { 243ac27a0ecSDave Kleikamp error = -ERANGE; 244ac27a0ecSDave Kleikamp if (size > buffer_size) 245ac27a0ecSDave Kleikamp goto cleanup; 246ac27a0ecSDave Kleikamp memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), 247ac27a0ecSDave Kleikamp size); 248ac27a0ecSDave Kleikamp } 249ac27a0ecSDave Kleikamp error = size; 250ac27a0ecSDave Kleikamp 251ac27a0ecSDave Kleikamp cleanup: 252ac27a0ecSDave Kleikamp brelse(bh); 253ac27a0ecSDave Kleikamp return error; 254ac27a0ecSDave Kleikamp } 255ac27a0ecSDave Kleikamp 256ac27a0ecSDave Kleikamp static int 257617ba13bSMingming Cao ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, 258ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 259ac27a0ecSDave Kleikamp { 260617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 261617ba13bSMingming Cao struct ext4_xattr_entry *entry; 262617ba13bSMingming Cao struct ext4_inode *raw_inode; 263617ba13bSMingming Cao struct ext4_iloc iloc; 264ac27a0ecSDave Kleikamp size_t size; 265ac27a0ecSDave Kleikamp void *end; 266ac27a0ecSDave Kleikamp int error; 267ac27a0ecSDave Kleikamp 268617ba13bSMingming Cao if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)) 269ac27a0ecSDave Kleikamp return -ENODATA; 270617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 271ac27a0ecSDave Kleikamp if (error) 272ac27a0ecSDave Kleikamp return error; 273617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 274ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 275ac27a0ecSDave Kleikamp entry = IFIRST(header); 276617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 277617ba13bSMingming Cao error = ext4_xattr_check_names(entry, end); 278ac27a0ecSDave Kleikamp if (error) 279ac27a0ecSDave Kleikamp goto cleanup; 280617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, 281ac27a0ecSDave Kleikamp end - (void *)entry, 0); 282ac27a0ecSDave Kleikamp if (error) 283ac27a0ecSDave Kleikamp goto cleanup; 284ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 285ac27a0ecSDave Kleikamp if (buffer) { 286ac27a0ecSDave Kleikamp error = -ERANGE; 287ac27a0ecSDave Kleikamp if (size > buffer_size) 288ac27a0ecSDave Kleikamp goto cleanup; 289ac27a0ecSDave Kleikamp memcpy(buffer, (void *)IFIRST(header) + 290ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs), size); 291ac27a0ecSDave Kleikamp } 292ac27a0ecSDave Kleikamp error = size; 293ac27a0ecSDave Kleikamp 294ac27a0ecSDave Kleikamp cleanup: 295ac27a0ecSDave Kleikamp brelse(iloc.bh); 296ac27a0ecSDave Kleikamp return error; 297ac27a0ecSDave Kleikamp } 298ac27a0ecSDave Kleikamp 299ac27a0ecSDave Kleikamp /* 300617ba13bSMingming Cao * ext4_xattr_get() 301ac27a0ecSDave Kleikamp * 302ac27a0ecSDave Kleikamp * Copy an extended attribute into the buffer 303ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 304ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 305ac27a0ecSDave Kleikamp * 306ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 307ac27a0ecSDave Kleikamp * used / required on success. 308ac27a0ecSDave Kleikamp */ 309ac27a0ecSDave Kleikamp int 310617ba13bSMingming Cao ext4_xattr_get(struct inode *inode, int name_index, const char *name, 311ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 312ac27a0ecSDave Kleikamp { 313ac27a0ecSDave Kleikamp int error; 314ac27a0ecSDave Kleikamp 315617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 316617ba13bSMingming Cao error = ext4_xattr_ibody_get(inode, name_index, name, buffer, 317ac27a0ecSDave Kleikamp buffer_size); 318ac27a0ecSDave Kleikamp if (error == -ENODATA) 319617ba13bSMingming Cao error = ext4_xattr_block_get(inode, name_index, name, buffer, 320ac27a0ecSDave Kleikamp buffer_size); 321617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 322ac27a0ecSDave Kleikamp return error; 323ac27a0ecSDave Kleikamp } 324ac27a0ecSDave Kleikamp 325ac27a0ecSDave Kleikamp static int 326617ba13bSMingming Cao ext4_xattr_list_entries(struct inode *inode, struct ext4_xattr_entry *entry, 327ac27a0ecSDave Kleikamp char *buffer, size_t buffer_size) 328ac27a0ecSDave Kleikamp { 329ac27a0ecSDave Kleikamp size_t rest = buffer_size; 330ac27a0ecSDave Kleikamp 331617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 332ac27a0ecSDave Kleikamp struct xattr_handler *handler = 333617ba13bSMingming Cao ext4_xattr_handler(entry->e_name_index); 334ac27a0ecSDave Kleikamp 335ac27a0ecSDave Kleikamp if (handler) { 336ac27a0ecSDave Kleikamp size_t size = handler->list(inode, buffer, rest, 337ac27a0ecSDave Kleikamp entry->e_name, 338ac27a0ecSDave Kleikamp entry->e_name_len); 339ac27a0ecSDave Kleikamp if (buffer) { 340ac27a0ecSDave Kleikamp if (size > rest) 341ac27a0ecSDave Kleikamp return -ERANGE; 342ac27a0ecSDave Kleikamp buffer += size; 343ac27a0ecSDave Kleikamp } 344ac27a0ecSDave Kleikamp rest -= size; 345ac27a0ecSDave Kleikamp } 346ac27a0ecSDave Kleikamp } 347ac27a0ecSDave Kleikamp return buffer_size - rest; 348ac27a0ecSDave Kleikamp } 349ac27a0ecSDave Kleikamp 350ac27a0ecSDave Kleikamp static int 351617ba13bSMingming Cao ext4_xattr_block_list(struct inode *inode, char *buffer, size_t buffer_size) 352ac27a0ecSDave Kleikamp { 353ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 354ac27a0ecSDave Kleikamp int error; 355ac27a0ecSDave Kleikamp 356ac27a0ecSDave Kleikamp ea_idebug(inode, "buffer=%p, buffer_size=%ld", 357ac27a0ecSDave Kleikamp buffer, (long)buffer_size); 358ac27a0ecSDave Kleikamp 359ac27a0ecSDave Kleikamp error = 0; 360617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 361ac27a0ecSDave Kleikamp goto cleanup; 362617ba13bSMingming Cao ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl); 363617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 364ac27a0ecSDave Kleikamp error = -EIO; 365ac27a0ecSDave Kleikamp if (!bh) 366ac27a0ecSDave Kleikamp goto cleanup; 367ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 368ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 369617ba13bSMingming Cao if (ext4_xattr_check_block(bh)) { 370617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 3712ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 372617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 373ac27a0ecSDave Kleikamp error = -EIO; 374ac27a0ecSDave Kleikamp goto cleanup; 375ac27a0ecSDave Kleikamp } 376617ba13bSMingming Cao ext4_xattr_cache_insert(bh); 377617ba13bSMingming Cao error = ext4_xattr_list_entries(inode, BFIRST(bh), buffer, buffer_size); 378ac27a0ecSDave Kleikamp 379ac27a0ecSDave Kleikamp cleanup: 380ac27a0ecSDave Kleikamp brelse(bh); 381ac27a0ecSDave Kleikamp 382ac27a0ecSDave Kleikamp return error; 383ac27a0ecSDave Kleikamp } 384ac27a0ecSDave Kleikamp 385ac27a0ecSDave Kleikamp static int 386617ba13bSMingming Cao ext4_xattr_ibody_list(struct inode *inode, char *buffer, size_t buffer_size) 387ac27a0ecSDave Kleikamp { 388617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 389617ba13bSMingming Cao struct ext4_inode *raw_inode; 390617ba13bSMingming Cao struct ext4_iloc iloc; 391ac27a0ecSDave Kleikamp void *end; 392ac27a0ecSDave Kleikamp int error; 393ac27a0ecSDave Kleikamp 394617ba13bSMingming Cao if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR)) 395ac27a0ecSDave Kleikamp return 0; 396617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 397ac27a0ecSDave Kleikamp if (error) 398ac27a0ecSDave Kleikamp return error; 399617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 400ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 401617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 402617ba13bSMingming Cao error = ext4_xattr_check_names(IFIRST(header), end); 403ac27a0ecSDave Kleikamp if (error) 404ac27a0ecSDave Kleikamp goto cleanup; 405617ba13bSMingming Cao error = ext4_xattr_list_entries(inode, IFIRST(header), 406ac27a0ecSDave Kleikamp buffer, buffer_size); 407ac27a0ecSDave Kleikamp 408ac27a0ecSDave Kleikamp cleanup: 409ac27a0ecSDave Kleikamp brelse(iloc.bh); 410ac27a0ecSDave Kleikamp return error; 411ac27a0ecSDave Kleikamp } 412ac27a0ecSDave Kleikamp 413ac27a0ecSDave Kleikamp /* 414617ba13bSMingming Cao * ext4_xattr_list() 415ac27a0ecSDave Kleikamp * 416ac27a0ecSDave Kleikamp * Copy a list of attribute names into the buffer 417ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 418ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 419ac27a0ecSDave Kleikamp * 420ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 421ac27a0ecSDave Kleikamp * used / required on success. 422ac27a0ecSDave Kleikamp */ 423ac27a0ecSDave Kleikamp int 424617ba13bSMingming Cao ext4_xattr_list(struct inode *inode, char *buffer, size_t buffer_size) 425ac27a0ecSDave Kleikamp { 426ac27a0ecSDave Kleikamp int i_error, b_error; 427ac27a0ecSDave Kleikamp 428617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 429617ba13bSMingming Cao i_error = ext4_xattr_ibody_list(inode, buffer, buffer_size); 430ac27a0ecSDave Kleikamp if (i_error < 0) { 431ac27a0ecSDave Kleikamp b_error = 0; 432ac27a0ecSDave Kleikamp } else { 433ac27a0ecSDave Kleikamp if (buffer) { 434ac27a0ecSDave Kleikamp buffer += i_error; 435ac27a0ecSDave Kleikamp buffer_size -= i_error; 436ac27a0ecSDave Kleikamp } 437617ba13bSMingming Cao b_error = ext4_xattr_block_list(inode, buffer, buffer_size); 438ac27a0ecSDave Kleikamp if (b_error < 0) 439ac27a0ecSDave Kleikamp i_error = 0; 440ac27a0ecSDave Kleikamp } 441617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 442ac27a0ecSDave Kleikamp return i_error + b_error; 443ac27a0ecSDave Kleikamp } 444ac27a0ecSDave Kleikamp 445ac27a0ecSDave Kleikamp /* 446617ba13bSMingming Cao * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is 447ac27a0ecSDave Kleikamp * not set, set it. 448ac27a0ecSDave Kleikamp */ 449617ba13bSMingming Cao static void ext4_xattr_update_super_block(handle_t *handle, 450ac27a0ecSDave Kleikamp struct super_block *sb) 451ac27a0ecSDave Kleikamp { 452617ba13bSMingming Cao if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR)) 453ac27a0ecSDave Kleikamp return; 454ac27a0ecSDave Kleikamp 455617ba13bSMingming Cao if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { 456ed2908f3SAndreas Gruenbacher EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR); 457ac27a0ecSDave Kleikamp sb->s_dirt = 1; 458617ba13bSMingming Cao ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh); 459ac27a0ecSDave Kleikamp } 460ac27a0ecSDave Kleikamp } 461ac27a0ecSDave Kleikamp 462ac27a0ecSDave Kleikamp /* 463ac27a0ecSDave Kleikamp * Release the xattr block BH: If the reference count is > 1, decrement 464ac27a0ecSDave Kleikamp * it; otherwise free the block. 465ac27a0ecSDave Kleikamp */ 466ac27a0ecSDave Kleikamp static void 467617ba13bSMingming Cao ext4_xattr_release_block(handle_t *handle, struct inode *inode, 468ac27a0ecSDave Kleikamp struct buffer_head *bh) 469ac27a0ecSDave Kleikamp { 470ac27a0ecSDave Kleikamp struct mb_cache_entry *ce = NULL; 4718a2bfdcbSMingming Cao int error = 0; 472ac27a0ecSDave Kleikamp 473617ba13bSMingming Cao ce = mb_cache_entry_get(ext4_xattr_cache, bh->b_bdev, bh->b_blocknr); 4748a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bh); 4758a2bfdcbSMingming Cao if (error) 4768a2bfdcbSMingming Cao goto out; 4778a2bfdcbSMingming Cao 4788a2bfdcbSMingming Cao lock_buffer(bh); 479ac27a0ecSDave Kleikamp if (BHDR(bh)->h_refcount == cpu_to_le32(1)) { 480ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=0; freeing"); 481ac27a0ecSDave Kleikamp if (ce) 482ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 483617ba13bSMingming Cao ext4_free_blocks(handle, inode, bh->b_blocknr, 1); 484ac27a0ecSDave Kleikamp get_bh(bh); 485617ba13bSMingming Cao ext4_forget(handle, 1, inode, bh, bh->b_blocknr); 486ac27a0ecSDave Kleikamp } else { 487ac27a0ecSDave Kleikamp BHDR(bh)->h_refcount = cpu_to_le32( 488ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount) - 1); 4898a2bfdcbSMingming Cao error = ext4_journal_dirty_metadata(handle, bh); 490ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 491ac27a0ecSDave Kleikamp handle->h_sync = 1; 492ac27a0ecSDave Kleikamp DQUOT_FREE_BLOCK(inode, 1); 493ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=%d; releasing", 494ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount)); 495ac27a0ecSDave Kleikamp if (ce) 496ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 497ac27a0ecSDave Kleikamp } 4988a2bfdcbSMingming Cao unlock_buffer(bh); 4998a2bfdcbSMingming Cao out: 5008a2bfdcbSMingming Cao ext4_std_error(inode->i_sb, error); 5018a2bfdcbSMingming Cao return; 502ac27a0ecSDave Kleikamp } 503ac27a0ecSDave Kleikamp 5046dd4ee7cSKalpak Shah /* 5056dd4ee7cSKalpak Shah * Find the available free space for EAs. This also returns the total number of 5066dd4ee7cSKalpak Shah * bytes used by EA entries. 5076dd4ee7cSKalpak Shah */ 5086dd4ee7cSKalpak Shah static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, 5096dd4ee7cSKalpak Shah size_t *min_offs, void *base, int *total) 5106dd4ee7cSKalpak Shah { 5116dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 5126dd4ee7cSKalpak Shah *total += EXT4_XATTR_LEN(last->e_name_len); 5136dd4ee7cSKalpak Shah if (!last->e_value_block && last->e_value_size) { 5146dd4ee7cSKalpak Shah size_t offs = le16_to_cpu(last->e_value_offs); 5156dd4ee7cSKalpak Shah if (offs < *min_offs) 5166dd4ee7cSKalpak Shah *min_offs = offs; 5176dd4ee7cSKalpak Shah } 5186dd4ee7cSKalpak Shah } 5196dd4ee7cSKalpak Shah return (*min_offs - ((void *)last - base) - sizeof(__u32)); 5206dd4ee7cSKalpak Shah } 5216dd4ee7cSKalpak Shah 522617ba13bSMingming Cao struct ext4_xattr_info { 523ac27a0ecSDave Kleikamp int name_index; 524ac27a0ecSDave Kleikamp const char *name; 525ac27a0ecSDave Kleikamp const void *value; 526ac27a0ecSDave Kleikamp size_t value_len; 527ac27a0ecSDave Kleikamp }; 528ac27a0ecSDave Kleikamp 529617ba13bSMingming Cao struct ext4_xattr_search { 530617ba13bSMingming Cao struct ext4_xattr_entry *first; 531ac27a0ecSDave Kleikamp void *base; 532ac27a0ecSDave Kleikamp void *end; 533617ba13bSMingming Cao struct ext4_xattr_entry *here; 534ac27a0ecSDave Kleikamp int not_found; 535ac27a0ecSDave Kleikamp }; 536ac27a0ecSDave Kleikamp 537ac27a0ecSDave Kleikamp static int 538617ba13bSMingming Cao ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) 539ac27a0ecSDave Kleikamp { 540617ba13bSMingming Cao struct ext4_xattr_entry *last; 541ac27a0ecSDave Kleikamp size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); 542ac27a0ecSDave Kleikamp 543ac27a0ecSDave Kleikamp /* Compute min_offs and last. */ 544ac27a0ecSDave Kleikamp last = s->first; 545617ba13bSMingming Cao for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 546ac27a0ecSDave Kleikamp if (!last->e_value_block && last->e_value_size) { 547ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(last->e_value_offs); 548ac27a0ecSDave Kleikamp if (offs < min_offs) 549ac27a0ecSDave Kleikamp min_offs = offs; 550ac27a0ecSDave Kleikamp } 551ac27a0ecSDave Kleikamp } 552ac27a0ecSDave Kleikamp free = min_offs - ((void *)last - s->base) - sizeof(__u32); 553ac27a0ecSDave Kleikamp if (!s->not_found) { 554ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 555ac27a0ecSDave Kleikamp size_t size = le32_to_cpu(s->here->e_value_size); 556617ba13bSMingming Cao free += EXT4_XATTR_SIZE(size); 557ac27a0ecSDave Kleikamp } 558617ba13bSMingming Cao free += EXT4_XATTR_LEN(name_len); 559ac27a0ecSDave Kleikamp } 560ac27a0ecSDave Kleikamp if (i->value) { 561617ba13bSMingming Cao if (free < EXT4_XATTR_SIZE(i->value_len) || 562617ba13bSMingming Cao free < EXT4_XATTR_LEN(name_len) + 563617ba13bSMingming Cao EXT4_XATTR_SIZE(i->value_len)) 564ac27a0ecSDave Kleikamp return -ENOSPC; 565ac27a0ecSDave Kleikamp } 566ac27a0ecSDave Kleikamp 567ac27a0ecSDave Kleikamp if (i->value && s->not_found) { 568ac27a0ecSDave Kleikamp /* Insert the new name. */ 569617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 570ac27a0ecSDave Kleikamp size_t rest = (void *)last - (void *)s->here + sizeof(__u32); 571ac27a0ecSDave Kleikamp memmove((void *)s->here + size, s->here, rest); 572ac27a0ecSDave Kleikamp memset(s->here, 0, size); 573ac27a0ecSDave Kleikamp s->here->e_name_index = i->name_index; 574ac27a0ecSDave Kleikamp s->here->e_name_len = name_len; 575ac27a0ecSDave Kleikamp memcpy(s->here->e_name, i->name, name_len); 576ac27a0ecSDave Kleikamp } else { 577ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 578ac27a0ecSDave Kleikamp void *first_val = s->base + min_offs; 579ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(s->here->e_value_offs); 580ac27a0ecSDave Kleikamp void *val = s->base + offs; 581617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE( 582ac27a0ecSDave Kleikamp le32_to_cpu(s->here->e_value_size)); 583ac27a0ecSDave Kleikamp 584617ba13bSMingming Cao if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { 585ac27a0ecSDave Kleikamp /* The old and the new value have the same 586ac27a0ecSDave Kleikamp size. Just replace. */ 587ac27a0ecSDave Kleikamp s->here->e_value_size = 588ac27a0ecSDave Kleikamp cpu_to_le32(i->value_len); 589617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 590617ba13bSMingming Cao EXT4_XATTR_PAD); /* Clear pad bytes. */ 591ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 592ac27a0ecSDave Kleikamp return 0; 593ac27a0ecSDave Kleikamp } 594ac27a0ecSDave Kleikamp 595ac27a0ecSDave Kleikamp /* Remove the old value. */ 596ac27a0ecSDave Kleikamp memmove(first_val + size, first_val, val - first_val); 597ac27a0ecSDave Kleikamp memset(first_val, 0, size); 598ac27a0ecSDave Kleikamp s->here->e_value_size = 0; 599ac27a0ecSDave Kleikamp s->here->e_value_offs = 0; 600ac27a0ecSDave Kleikamp min_offs += size; 601ac27a0ecSDave Kleikamp 602ac27a0ecSDave Kleikamp /* Adjust all value offsets. */ 603ac27a0ecSDave Kleikamp last = s->first; 604ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(last)) { 605ac27a0ecSDave Kleikamp size_t o = le16_to_cpu(last->e_value_offs); 606ac27a0ecSDave Kleikamp if (!last->e_value_block && 607ac27a0ecSDave Kleikamp last->e_value_size && o < offs) 608ac27a0ecSDave Kleikamp last->e_value_offs = 609ac27a0ecSDave Kleikamp cpu_to_le16(o + size); 610617ba13bSMingming Cao last = EXT4_XATTR_NEXT(last); 611ac27a0ecSDave Kleikamp } 612ac27a0ecSDave Kleikamp } 613ac27a0ecSDave Kleikamp if (!i->value) { 614ac27a0ecSDave Kleikamp /* Remove the old name. */ 615617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 616ac27a0ecSDave Kleikamp last = ENTRY((void *)last - size); 617ac27a0ecSDave Kleikamp memmove(s->here, (void *)s->here + size, 618ac27a0ecSDave Kleikamp (void *)last - (void *)s->here + sizeof(__u32)); 619ac27a0ecSDave Kleikamp memset(last, 0, size); 620ac27a0ecSDave Kleikamp } 621ac27a0ecSDave Kleikamp } 622ac27a0ecSDave Kleikamp 623ac27a0ecSDave Kleikamp if (i->value) { 624ac27a0ecSDave Kleikamp /* Insert the new value. */ 625ac27a0ecSDave Kleikamp s->here->e_value_size = cpu_to_le32(i->value_len); 626ac27a0ecSDave Kleikamp if (i->value_len) { 627617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE(i->value_len); 628ac27a0ecSDave Kleikamp void *val = s->base + min_offs - size; 629ac27a0ecSDave Kleikamp s->here->e_value_offs = cpu_to_le16(min_offs - size); 630617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 631617ba13bSMingming Cao EXT4_XATTR_PAD); /* Clear the pad bytes. */ 632ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 633ac27a0ecSDave Kleikamp } 634ac27a0ecSDave Kleikamp } 635ac27a0ecSDave Kleikamp return 0; 636ac27a0ecSDave Kleikamp } 637ac27a0ecSDave Kleikamp 638617ba13bSMingming Cao struct ext4_xattr_block_find { 639617ba13bSMingming Cao struct ext4_xattr_search s; 640ac27a0ecSDave Kleikamp struct buffer_head *bh; 641ac27a0ecSDave Kleikamp }; 642ac27a0ecSDave Kleikamp 643ac27a0ecSDave Kleikamp static int 644617ba13bSMingming Cao ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, 645617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 646ac27a0ecSDave Kleikamp { 647ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 648ac27a0ecSDave Kleikamp int error; 649ac27a0ecSDave Kleikamp 650ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", 651ac27a0ecSDave Kleikamp i->name_index, i->name, i->value, (long)i->value_len); 652ac27a0ecSDave Kleikamp 653617ba13bSMingming Cao if (EXT4_I(inode)->i_file_acl) { 654ac27a0ecSDave Kleikamp /* The inode already has an extended attribute block. */ 655617ba13bSMingming Cao bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); 656ac27a0ecSDave Kleikamp error = -EIO; 657ac27a0ecSDave Kleikamp if (!bs->bh) 658ac27a0ecSDave Kleikamp goto cleanup; 659ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "b_count=%d, refcount=%d", 660ac27a0ecSDave Kleikamp atomic_read(&(bs->bh->b_count)), 661ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bs->bh)->h_refcount)); 662617ba13bSMingming Cao if (ext4_xattr_check_block(bs->bh)) { 663617ba13bSMingming Cao ext4_error(sb, __FUNCTION__, 6642ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 665617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 666ac27a0ecSDave Kleikamp error = -EIO; 667ac27a0ecSDave Kleikamp goto cleanup; 668ac27a0ecSDave Kleikamp } 669ac27a0ecSDave Kleikamp /* Find the named attribute. */ 670ac27a0ecSDave Kleikamp bs->s.base = BHDR(bs->bh); 671ac27a0ecSDave Kleikamp bs->s.first = BFIRST(bs->bh); 672ac27a0ecSDave Kleikamp bs->s.end = bs->bh->b_data + bs->bh->b_size; 673ac27a0ecSDave Kleikamp bs->s.here = bs->s.first; 674617ba13bSMingming Cao error = ext4_xattr_find_entry(&bs->s.here, i->name_index, 675ac27a0ecSDave Kleikamp i->name, bs->bh->b_size, 1); 676ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 677ac27a0ecSDave Kleikamp goto cleanup; 678ac27a0ecSDave Kleikamp bs->s.not_found = error; 679ac27a0ecSDave Kleikamp } 680ac27a0ecSDave Kleikamp error = 0; 681ac27a0ecSDave Kleikamp 682ac27a0ecSDave Kleikamp cleanup: 683ac27a0ecSDave Kleikamp return error; 684ac27a0ecSDave Kleikamp } 685ac27a0ecSDave Kleikamp 686ac27a0ecSDave Kleikamp static int 687617ba13bSMingming Cao ext4_xattr_block_set(handle_t *handle, struct inode *inode, 688617ba13bSMingming Cao struct ext4_xattr_info *i, 689617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 690ac27a0ecSDave Kleikamp { 691ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 692ac27a0ecSDave Kleikamp struct buffer_head *new_bh = NULL; 693617ba13bSMingming Cao struct ext4_xattr_search *s = &bs->s; 694ac27a0ecSDave Kleikamp struct mb_cache_entry *ce = NULL; 6958a2bfdcbSMingming Cao int error = 0; 696ac27a0ecSDave Kleikamp 697617ba13bSMingming Cao #define header(x) ((struct ext4_xattr_header *)(x)) 698ac27a0ecSDave Kleikamp 699ac27a0ecSDave Kleikamp if (i->value && i->value_len > sb->s_blocksize) 700ac27a0ecSDave Kleikamp return -ENOSPC; 701ac27a0ecSDave Kleikamp if (s->base) { 702617ba13bSMingming Cao ce = mb_cache_entry_get(ext4_xattr_cache, bs->bh->b_bdev, 703ac27a0ecSDave Kleikamp bs->bh->b_blocknr); 7048a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bs->bh); 7058a2bfdcbSMingming Cao if (error) 7068a2bfdcbSMingming Cao goto cleanup; 7078a2bfdcbSMingming Cao lock_buffer(bs->bh); 7088a2bfdcbSMingming Cao 709ac27a0ecSDave Kleikamp if (header(s->base)->h_refcount == cpu_to_le32(1)) { 710ac27a0ecSDave Kleikamp if (ce) { 711ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 712ac27a0ecSDave Kleikamp ce = NULL; 713ac27a0ecSDave Kleikamp } 714ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "modifying in-place"); 715617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 716ac27a0ecSDave Kleikamp if (!error) { 717ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 718617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), 719ac27a0ecSDave Kleikamp s->here); 720617ba13bSMingming Cao ext4_xattr_cache_insert(bs->bh); 721ac27a0ecSDave Kleikamp } 722ac27a0ecSDave Kleikamp unlock_buffer(bs->bh); 723ac27a0ecSDave Kleikamp if (error == -EIO) 724ac27a0ecSDave Kleikamp goto bad_block; 725ac27a0ecSDave Kleikamp if (!error) 726617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, 727ac27a0ecSDave Kleikamp bs->bh); 728ac27a0ecSDave Kleikamp if (error) 729ac27a0ecSDave Kleikamp goto cleanup; 730ac27a0ecSDave Kleikamp goto inserted; 731ac27a0ecSDave Kleikamp } else { 732ac27a0ecSDave Kleikamp int offset = (char *)s->here - bs->bh->b_data; 733ac27a0ecSDave Kleikamp 7348a2bfdcbSMingming Cao unlock_buffer(bs->bh); 7358a2bfdcbSMingming Cao jbd2_journal_release_buffer(handle, bs->bh); 736ac27a0ecSDave Kleikamp if (ce) { 737ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 738ac27a0ecSDave Kleikamp ce = NULL; 739ac27a0ecSDave Kleikamp } 740ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "cloning"); 741ac27a0ecSDave Kleikamp s->base = kmalloc(bs->bh->b_size, GFP_KERNEL); 742ac27a0ecSDave Kleikamp error = -ENOMEM; 743ac27a0ecSDave Kleikamp if (s->base == NULL) 744ac27a0ecSDave Kleikamp goto cleanup; 745ac27a0ecSDave Kleikamp memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); 746ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 747ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 748ac27a0ecSDave Kleikamp s->here = ENTRY(s->base + offset); 749ac27a0ecSDave Kleikamp s->end = s->base + bs->bh->b_size; 750ac27a0ecSDave Kleikamp } 751ac27a0ecSDave Kleikamp } else { 752ac27a0ecSDave Kleikamp /* Allocate a buffer where we construct the new block. */ 753d802ffa8SMingming Cao s->base = kzalloc(sb->s_blocksize, GFP_KERNEL); 754ac27a0ecSDave Kleikamp /* assert(header == s->base) */ 755ac27a0ecSDave Kleikamp error = -ENOMEM; 756ac27a0ecSDave Kleikamp if (s->base == NULL) 757ac27a0ecSDave Kleikamp goto cleanup; 758617ba13bSMingming Cao header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 759ac27a0ecSDave Kleikamp header(s->base)->h_blocks = cpu_to_le32(1); 760ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 761ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 762ac27a0ecSDave Kleikamp s->here = ENTRY(header(s->base)+1); 763ac27a0ecSDave Kleikamp s->end = s->base + sb->s_blocksize; 764ac27a0ecSDave Kleikamp } 765ac27a0ecSDave Kleikamp 766617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 767ac27a0ecSDave Kleikamp if (error == -EIO) 768ac27a0ecSDave Kleikamp goto bad_block; 769ac27a0ecSDave Kleikamp if (error) 770ac27a0ecSDave Kleikamp goto cleanup; 771ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 772617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), s->here); 773ac27a0ecSDave Kleikamp 774ac27a0ecSDave Kleikamp inserted: 775ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 776617ba13bSMingming Cao new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); 777ac27a0ecSDave Kleikamp if (new_bh) { 778ac27a0ecSDave Kleikamp /* We found an identical block in the cache. */ 779ac27a0ecSDave Kleikamp if (new_bh == bs->bh) 780ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "keeping"); 781ac27a0ecSDave Kleikamp else { 782ac27a0ecSDave Kleikamp /* The old block is released after updating 783ac27a0ecSDave Kleikamp the inode. */ 784ac27a0ecSDave Kleikamp error = -EDQUOT; 785ac27a0ecSDave Kleikamp if (DQUOT_ALLOC_BLOCK(inode, 1)) 786ac27a0ecSDave Kleikamp goto cleanup; 787617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, 788ac27a0ecSDave Kleikamp new_bh); 789ac27a0ecSDave Kleikamp if (error) 790ac27a0ecSDave Kleikamp goto cleanup_dquot; 791ac27a0ecSDave Kleikamp lock_buffer(new_bh); 792ac27a0ecSDave Kleikamp BHDR(new_bh)->h_refcount = cpu_to_le32(1 + 793ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(new_bh)->h_refcount)); 794ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "reusing; refcount now=%d", 795ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(new_bh)->h_refcount)); 796ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 797617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, 798ac27a0ecSDave Kleikamp new_bh); 799ac27a0ecSDave Kleikamp if (error) 800ac27a0ecSDave Kleikamp goto cleanup_dquot; 801ac27a0ecSDave Kleikamp } 802ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 803ac27a0ecSDave Kleikamp ce = NULL; 804ac27a0ecSDave Kleikamp } else if (bs->bh && s->base == bs->bh->b_data) { 805ac27a0ecSDave Kleikamp /* We were modifying this block in-place. */ 806ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "keeping this block"); 807ac27a0ecSDave Kleikamp new_bh = bs->bh; 808ac27a0ecSDave Kleikamp get_bh(new_bh); 809ac27a0ecSDave Kleikamp } else { 810ac27a0ecSDave Kleikamp /* We need to allocate a new block */ 811617ba13bSMingming Cao ext4_fsblk_t goal = le32_to_cpu( 812617ba13bSMingming Cao EXT4_SB(sb)->s_es->s_first_data_block) + 813617ba13bSMingming Cao (ext4_fsblk_t)EXT4_I(inode)->i_block_group * 814617ba13bSMingming Cao EXT4_BLOCKS_PER_GROUP(sb); 815617ba13bSMingming Cao ext4_fsblk_t block = ext4_new_block(handle, inode, 816ac27a0ecSDave Kleikamp goal, &error); 817ac27a0ecSDave Kleikamp if (error) 818ac27a0ecSDave Kleikamp goto cleanup; 819ac27a0ecSDave Kleikamp ea_idebug(inode, "creating block %d", block); 820ac27a0ecSDave Kleikamp 821ac27a0ecSDave Kleikamp new_bh = sb_getblk(sb, block); 822ac27a0ecSDave Kleikamp if (!new_bh) { 823ac27a0ecSDave Kleikamp getblk_failed: 824617ba13bSMingming Cao ext4_free_blocks(handle, inode, block, 1); 825ac27a0ecSDave Kleikamp error = -EIO; 826ac27a0ecSDave Kleikamp goto cleanup; 827ac27a0ecSDave Kleikamp } 828ac27a0ecSDave Kleikamp lock_buffer(new_bh); 829617ba13bSMingming Cao error = ext4_journal_get_create_access(handle, new_bh); 830ac27a0ecSDave Kleikamp if (error) { 831ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 832ac27a0ecSDave Kleikamp goto getblk_failed; 833ac27a0ecSDave Kleikamp } 834ac27a0ecSDave Kleikamp memcpy(new_bh->b_data, s->base, new_bh->b_size); 835ac27a0ecSDave Kleikamp set_buffer_uptodate(new_bh); 836ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 837617ba13bSMingming Cao ext4_xattr_cache_insert(new_bh); 838617ba13bSMingming Cao error = ext4_journal_dirty_metadata(handle, new_bh); 839ac27a0ecSDave Kleikamp if (error) 840ac27a0ecSDave Kleikamp goto cleanup; 841ac27a0ecSDave Kleikamp } 842ac27a0ecSDave Kleikamp } 843ac27a0ecSDave Kleikamp 844ac27a0ecSDave Kleikamp /* Update the inode. */ 845617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; 846ac27a0ecSDave Kleikamp 847ac27a0ecSDave Kleikamp /* Drop the previous xattr block. */ 848ac27a0ecSDave Kleikamp if (bs->bh && bs->bh != new_bh) 849617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bs->bh); 850ac27a0ecSDave Kleikamp error = 0; 851ac27a0ecSDave Kleikamp 852ac27a0ecSDave Kleikamp cleanup: 853ac27a0ecSDave Kleikamp if (ce) 854ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 855ac27a0ecSDave Kleikamp brelse(new_bh); 856ac27a0ecSDave Kleikamp if (!(bs->bh && s->base == bs->bh->b_data)) 857ac27a0ecSDave Kleikamp kfree(s->base); 858ac27a0ecSDave Kleikamp 859ac27a0ecSDave Kleikamp return error; 860ac27a0ecSDave Kleikamp 861ac27a0ecSDave Kleikamp cleanup_dquot: 862ac27a0ecSDave Kleikamp DQUOT_FREE_BLOCK(inode, 1); 863ac27a0ecSDave Kleikamp goto cleanup; 864ac27a0ecSDave Kleikamp 865ac27a0ecSDave Kleikamp bad_block: 866617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 8672ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 868617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 869ac27a0ecSDave Kleikamp goto cleanup; 870ac27a0ecSDave Kleikamp 871ac27a0ecSDave Kleikamp #undef header 872ac27a0ecSDave Kleikamp } 873ac27a0ecSDave Kleikamp 874617ba13bSMingming Cao struct ext4_xattr_ibody_find { 875617ba13bSMingming Cao struct ext4_xattr_search s; 876617ba13bSMingming Cao struct ext4_iloc iloc; 877ac27a0ecSDave Kleikamp }; 878ac27a0ecSDave Kleikamp 879ac27a0ecSDave Kleikamp static int 880617ba13bSMingming Cao ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, 881617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 882ac27a0ecSDave Kleikamp { 883617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 884617ba13bSMingming Cao struct ext4_inode *raw_inode; 885ac27a0ecSDave Kleikamp int error; 886ac27a0ecSDave Kleikamp 887617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 888ac27a0ecSDave Kleikamp return 0; 889617ba13bSMingming Cao raw_inode = ext4_raw_inode(&is->iloc); 890ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 891ac27a0ecSDave Kleikamp is->s.base = is->s.first = IFIRST(header); 892ac27a0ecSDave Kleikamp is->s.here = is->s.first; 893617ba13bSMingming Cao is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 894617ba13bSMingming Cao if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) { 895617ba13bSMingming Cao error = ext4_xattr_check_names(IFIRST(header), is->s.end); 896ac27a0ecSDave Kleikamp if (error) 897ac27a0ecSDave Kleikamp return error; 898ac27a0ecSDave Kleikamp /* Find the named attribute. */ 899617ba13bSMingming Cao error = ext4_xattr_find_entry(&is->s.here, i->name_index, 900ac27a0ecSDave Kleikamp i->name, is->s.end - 901ac27a0ecSDave Kleikamp (void *)is->s.base, 0); 902ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 903ac27a0ecSDave Kleikamp return error; 904ac27a0ecSDave Kleikamp is->s.not_found = error; 905ac27a0ecSDave Kleikamp } 906ac27a0ecSDave Kleikamp return 0; 907ac27a0ecSDave Kleikamp } 908ac27a0ecSDave Kleikamp 909ac27a0ecSDave Kleikamp static int 910617ba13bSMingming Cao ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, 911617ba13bSMingming Cao struct ext4_xattr_info *i, 912617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 913ac27a0ecSDave Kleikamp { 914617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 915617ba13bSMingming Cao struct ext4_xattr_search *s = &is->s; 916ac27a0ecSDave Kleikamp int error; 917ac27a0ecSDave Kleikamp 918617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 919ac27a0ecSDave Kleikamp return -ENOSPC; 920617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 921ac27a0ecSDave Kleikamp if (error) 922ac27a0ecSDave Kleikamp return error; 923617ba13bSMingming Cao header = IHDR(inode, ext4_raw_inode(&is->iloc)); 924ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 925617ba13bSMingming Cao header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 926617ba13bSMingming Cao EXT4_I(inode)->i_state |= EXT4_STATE_XATTR; 927ac27a0ecSDave Kleikamp } else { 928ac27a0ecSDave Kleikamp header->h_magic = cpu_to_le32(0); 929617ba13bSMingming Cao EXT4_I(inode)->i_state &= ~EXT4_STATE_XATTR; 930ac27a0ecSDave Kleikamp } 931ac27a0ecSDave Kleikamp return 0; 932ac27a0ecSDave Kleikamp } 933ac27a0ecSDave Kleikamp 934ac27a0ecSDave Kleikamp /* 935617ba13bSMingming Cao * ext4_xattr_set_handle() 936ac27a0ecSDave Kleikamp * 937ac27a0ecSDave Kleikamp * Create, replace or remove an extended attribute for this inode. Buffer 938ac27a0ecSDave Kleikamp * is NULL to remove an existing extended attribute, and non-NULL to 939ac27a0ecSDave Kleikamp * either replace an existing extended attribute, or create a new extended 940ac27a0ecSDave Kleikamp * attribute. The flags XATTR_REPLACE and XATTR_CREATE 941ac27a0ecSDave Kleikamp * specify that an extended attribute must exist and must not exist 942ac27a0ecSDave Kleikamp * previous to the call, respectively. 943ac27a0ecSDave Kleikamp * 944ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 945ac27a0ecSDave Kleikamp */ 946ac27a0ecSDave Kleikamp int 947617ba13bSMingming Cao ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, 948ac27a0ecSDave Kleikamp const char *name, const void *value, size_t value_len, 949ac27a0ecSDave Kleikamp int flags) 950ac27a0ecSDave Kleikamp { 951617ba13bSMingming Cao struct ext4_xattr_info i = { 952ac27a0ecSDave Kleikamp .name_index = name_index, 953ac27a0ecSDave Kleikamp .name = name, 954ac27a0ecSDave Kleikamp .value = value, 955ac27a0ecSDave Kleikamp .value_len = value_len, 956ac27a0ecSDave Kleikamp 957ac27a0ecSDave Kleikamp }; 958617ba13bSMingming Cao struct ext4_xattr_ibody_find is = { 959ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 960ac27a0ecSDave Kleikamp }; 961617ba13bSMingming Cao struct ext4_xattr_block_find bs = { 962ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 963ac27a0ecSDave Kleikamp }; 964ac27a0ecSDave Kleikamp int error; 965ac27a0ecSDave Kleikamp 966ac27a0ecSDave Kleikamp if (!name) 967ac27a0ecSDave Kleikamp return -EINVAL; 968ac27a0ecSDave Kleikamp if (strlen(name) > 255) 969ac27a0ecSDave Kleikamp return -ERANGE; 970617ba13bSMingming Cao down_write(&EXT4_I(inode)->xattr_sem); 971617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &is.iloc); 972ac27a0ecSDave Kleikamp if (error) 973ac27a0ecSDave Kleikamp goto cleanup; 974ac27a0ecSDave Kleikamp 975617ba13bSMingming Cao if (EXT4_I(inode)->i_state & EXT4_STATE_NEW) { 976617ba13bSMingming Cao struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); 977617ba13bSMingming Cao memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); 978617ba13bSMingming Cao EXT4_I(inode)->i_state &= ~EXT4_STATE_NEW; 979ac27a0ecSDave Kleikamp } 980ac27a0ecSDave Kleikamp 981617ba13bSMingming Cao error = ext4_xattr_ibody_find(inode, &i, &is); 982ac27a0ecSDave Kleikamp if (error) 983ac27a0ecSDave Kleikamp goto cleanup; 984ac27a0ecSDave Kleikamp if (is.s.not_found) 985617ba13bSMingming Cao error = ext4_xattr_block_find(inode, &i, &bs); 986ac27a0ecSDave Kleikamp if (error) 987ac27a0ecSDave Kleikamp goto cleanup; 988ac27a0ecSDave Kleikamp if (is.s.not_found && bs.s.not_found) { 989ac27a0ecSDave Kleikamp error = -ENODATA; 990ac27a0ecSDave Kleikamp if (flags & XATTR_REPLACE) 991ac27a0ecSDave Kleikamp goto cleanup; 992ac27a0ecSDave Kleikamp error = 0; 993ac27a0ecSDave Kleikamp if (!value) 994ac27a0ecSDave Kleikamp goto cleanup; 995ac27a0ecSDave Kleikamp } else { 996ac27a0ecSDave Kleikamp error = -EEXIST; 997ac27a0ecSDave Kleikamp if (flags & XATTR_CREATE) 998ac27a0ecSDave Kleikamp goto cleanup; 999ac27a0ecSDave Kleikamp } 1000617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, is.iloc.bh); 1001ac27a0ecSDave Kleikamp if (error) 1002ac27a0ecSDave Kleikamp goto cleanup; 1003ac27a0ecSDave Kleikamp if (!value) { 1004ac27a0ecSDave Kleikamp if (!is.s.not_found) 1005617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1006ac27a0ecSDave Kleikamp else if (!bs.s.not_found) 1007617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1008ac27a0ecSDave Kleikamp } else { 1009617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1010ac27a0ecSDave Kleikamp if (!error && !bs.s.not_found) { 1011ac27a0ecSDave Kleikamp i.value = NULL; 1012617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1013ac27a0ecSDave Kleikamp } else if (error == -ENOSPC) { 1014617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1015ac27a0ecSDave Kleikamp if (error) 1016ac27a0ecSDave Kleikamp goto cleanup; 1017ac27a0ecSDave Kleikamp if (!is.s.not_found) { 1018ac27a0ecSDave Kleikamp i.value = NULL; 1019617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, 1020ac27a0ecSDave Kleikamp &is); 1021ac27a0ecSDave Kleikamp } 1022ac27a0ecSDave Kleikamp } 1023ac27a0ecSDave Kleikamp } 1024ac27a0ecSDave Kleikamp if (!error) { 1025617ba13bSMingming Cao ext4_xattr_update_super_block(handle, inode->i_sb); 1026ef7f3835SKalpak Shah inode->i_ctime = ext4_current_time(inode); 10276dd4ee7cSKalpak Shah if (!value) 10286dd4ee7cSKalpak Shah EXT4_I(inode)->i_state &= ~EXT4_STATE_NO_EXPAND; 1029617ba13bSMingming Cao error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); 1030ac27a0ecSDave Kleikamp /* 1031617ba13bSMingming Cao * The bh is consumed by ext4_mark_iloc_dirty, even with 1032ac27a0ecSDave Kleikamp * error != 0. 1033ac27a0ecSDave Kleikamp */ 1034ac27a0ecSDave Kleikamp is.iloc.bh = NULL; 1035ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 1036ac27a0ecSDave Kleikamp handle->h_sync = 1; 1037ac27a0ecSDave Kleikamp } 1038ac27a0ecSDave Kleikamp 1039ac27a0ecSDave Kleikamp cleanup: 1040ac27a0ecSDave Kleikamp brelse(is.iloc.bh); 1041ac27a0ecSDave Kleikamp brelse(bs.bh); 1042617ba13bSMingming Cao up_write(&EXT4_I(inode)->xattr_sem); 1043ac27a0ecSDave Kleikamp return error; 1044ac27a0ecSDave Kleikamp } 1045ac27a0ecSDave Kleikamp 1046ac27a0ecSDave Kleikamp /* 1047617ba13bSMingming Cao * ext4_xattr_set() 1048ac27a0ecSDave Kleikamp * 1049617ba13bSMingming Cao * Like ext4_xattr_set_handle, but start from an inode. This extended 1050ac27a0ecSDave Kleikamp * attribute modification is a filesystem transaction by itself. 1051ac27a0ecSDave Kleikamp * 1052ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1053ac27a0ecSDave Kleikamp */ 1054ac27a0ecSDave Kleikamp int 1055617ba13bSMingming Cao ext4_xattr_set(struct inode *inode, int name_index, const char *name, 1056ac27a0ecSDave Kleikamp const void *value, size_t value_len, int flags) 1057ac27a0ecSDave Kleikamp { 1058ac27a0ecSDave Kleikamp handle_t *handle; 1059ac27a0ecSDave Kleikamp int error, retries = 0; 1060ac27a0ecSDave Kleikamp 1061ac27a0ecSDave Kleikamp retry: 1062617ba13bSMingming Cao handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb)); 1063ac27a0ecSDave Kleikamp if (IS_ERR(handle)) { 1064ac27a0ecSDave Kleikamp error = PTR_ERR(handle); 1065ac27a0ecSDave Kleikamp } else { 1066ac27a0ecSDave Kleikamp int error2; 1067ac27a0ecSDave Kleikamp 1068617ba13bSMingming Cao error = ext4_xattr_set_handle(handle, inode, name_index, name, 1069ac27a0ecSDave Kleikamp value, value_len, flags); 1070617ba13bSMingming Cao error2 = ext4_journal_stop(handle); 1071ac27a0ecSDave Kleikamp if (error == -ENOSPC && 1072617ba13bSMingming Cao ext4_should_retry_alloc(inode->i_sb, &retries)) 1073ac27a0ecSDave Kleikamp goto retry; 1074ac27a0ecSDave Kleikamp if (error == 0) 1075ac27a0ecSDave Kleikamp error = error2; 1076ac27a0ecSDave Kleikamp } 1077ac27a0ecSDave Kleikamp 1078ac27a0ecSDave Kleikamp return error; 1079ac27a0ecSDave Kleikamp } 1080ac27a0ecSDave Kleikamp 1081ac27a0ecSDave Kleikamp /* 10826dd4ee7cSKalpak Shah * Shift the EA entries in the inode to create space for the increased 10836dd4ee7cSKalpak Shah * i_extra_isize. 10846dd4ee7cSKalpak Shah */ 10856dd4ee7cSKalpak Shah static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, 10866dd4ee7cSKalpak Shah int value_offs_shift, void *to, 10876dd4ee7cSKalpak Shah void *from, size_t n, int blocksize) 10886dd4ee7cSKalpak Shah { 10896dd4ee7cSKalpak Shah struct ext4_xattr_entry *last = entry; 10906dd4ee7cSKalpak Shah int new_offs; 10916dd4ee7cSKalpak Shah 10926dd4ee7cSKalpak Shah /* Adjust the value offsets of the entries */ 10936dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 10946dd4ee7cSKalpak Shah if (!last->e_value_block && last->e_value_size) { 10956dd4ee7cSKalpak Shah new_offs = le16_to_cpu(last->e_value_offs) + 10966dd4ee7cSKalpak Shah value_offs_shift; 10976dd4ee7cSKalpak Shah BUG_ON(new_offs + le32_to_cpu(last->e_value_size) 10986dd4ee7cSKalpak Shah > blocksize); 10996dd4ee7cSKalpak Shah last->e_value_offs = cpu_to_le16(new_offs); 11006dd4ee7cSKalpak Shah } 11016dd4ee7cSKalpak Shah } 11026dd4ee7cSKalpak Shah /* Shift the entries by n bytes */ 11036dd4ee7cSKalpak Shah memmove(to, from, n); 11046dd4ee7cSKalpak Shah } 11056dd4ee7cSKalpak Shah 11066dd4ee7cSKalpak Shah /* 11076dd4ee7cSKalpak Shah * Expand an inode by new_extra_isize bytes when EAs are present. 11086dd4ee7cSKalpak Shah * Returns 0 on success or negative error number on failure. 11096dd4ee7cSKalpak Shah */ 11106dd4ee7cSKalpak Shah int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, 11116dd4ee7cSKalpak Shah struct ext4_inode *raw_inode, handle_t *handle) 11126dd4ee7cSKalpak Shah { 11136dd4ee7cSKalpak Shah struct ext4_xattr_ibody_header *header; 11146dd4ee7cSKalpak Shah struct ext4_xattr_entry *entry, *last, *first; 11156dd4ee7cSKalpak Shah struct buffer_head *bh = NULL; 11166dd4ee7cSKalpak Shah struct ext4_xattr_ibody_find *is = NULL; 11176dd4ee7cSKalpak Shah struct ext4_xattr_block_find *bs = NULL; 11186dd4ee7cSKalpak Shah char *buffer = NULL, *b_entry_name = NULL; 11196dd4ee7cSKalpak Shah size_t min_offs, free; 11206dd4ee7cSKalpak Shah int total_ino, total_blk; 11216dd4ee7cSKalpak Shah void *base, *start, *end; 11226dd4ee7cSKalpak Shah int extra_isize = 0, error = 0, tried_min_extra_isize = 0; 1123*ac39849dSAneesh Kumar K.V int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); 11246dd4ee7cSKalpak Shah 11256dd4ee7cSKalpak Shah down_write(&EXT4_I(inode)->xattr_sem); 11266dd4ee7cSKalpak Shah retry: 11276dd4ee7cSKalpak Shah if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) { 11286dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 11296dd4ee7cSKalpak Shah return 0; 11306dd4ee7cSKalpak Shah } 11316dd4ee7cSKalpak Shah 11326dd4ee7cSKalpak Shah header = IHDR(inode, raw_inode); 11336dd4ee7cSKalpak Shah entry = IFIRST(header); 11346dd4ee7cSKalpak Shah 11356dd4ee7cSKalpak Shah /* 11366dd4ee7cSKalpak Shah * Check if enough free space is available in the inode to shift the 11376dd4ee7cSKalpak Shah * entries ahead by new_extra_isize. 11386dd4ee7cSKalpak Shah */ 11396dd4ee7cSKalpak Shah 11406dd4ee7cSKalpak Shah base = start = entry; 11416dd4ee7cSKalpak Shah end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 11426dd4ee7cSKalpak Shah min_offs = end - base; 11436dd4ee7cSKalpak Shah last = entry; 11446dd4ee7cSKalpak Shah total_ino = sizeof(struct ext4_xattr_ibody_header); 11456dd4ee7cSKalpak Shah 11466dd4ee7cSKalpak Shah free = ext4_xattr_free_space(last, &min_offs, base, &total_ino); 11476dd4ee7cSKalpak Shah if (free >= new_extra_isize) { 11486dd4ee7cSKalpak Shah entry = IFIRST(header); 11496dd4ee7cSKalpak Shah ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize 11506dd4ee7cSKalpak Shah - new_extra_isize, (void *)raw_inode + 11516dd4ee7cSKalpak Shah EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, 11526dd4ee7cSKalpak Shah (void *)header, total_ino, 11536dd4ee7cSKalpak Shah inode->i_sb->s_blocksize); 11546dd4ee7cSKalpak Shah EXT4_I(inode)->i_extra_isize = new_extra_isize; 11556dd4ee7cSKalpak Shah error = 0; 11566dd4ee7cSKalpak Shah goto cleanup; 11576dd4ee7cSKalpak Shah } 11586dd4ee7cSKalpak Shah 11596dd4ee7cSKalpak Shah /* 11606dd4ee7cSKalpak Shah * Enough free space isn't available in the inode, check if 11616dd4ee7cSKalpak Shah * EA block can hold new_extra_isize bytes. 11626dd4ee7cSKalpak Shah */ 11636dd4ee7cSKalpak Shah if (EXT4_I(inode)->i_file_acl) { 11646dd4ee7cSKalpak Shah bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 11656dd4ee7cSKalpak Shah error = -EIO; 11666dd4ee7cSKalpak Shah if (!bh) 11676dd4ee7cSKalpak Shah goto cleanup; 11686dd4ee7cSKalpak Shah if (ext4_xattr_check_block(bh)) { 11696dd4ee7cSKalpak Shah ext4_error(inode->i_sb, __FUNCTION__, 11706dd4ee7cSKalpak Shah "inode %lu: bad block %llu", inode->i_ino, 11716dd4ee7cSKalpak Shah EXT4_I(inode)->i_file_acl); 11726dd4ee7cSKalpak Shah error = -EIO; 11736dd4ee7cSKalpak Shah goto cleanup; 11746dd4ee7cSKalpak Shah } 11756dd4ee7cSKalpak Shah base = BHDR(bh); 11766dd4ee7cSKalpak Shah first = BFIRST(bh); 11776dd4ee7cSKalpak Shah end = bh->b_data + bh->b_size; 11786dd4ee7cSKalpak Shah min_offs = end - base; 11796dd4ee7cSKalpak Shah free = ext4_xattr_free_space(first, &min_offs, base, 11806dd4ee7cSKalpak Shah &total_blk); 11816dd4ee7cSKalpak Shah if (free < new_extra_isize) { 11826dd4ee7cSKalpak Shah if (!tried_min_extra_isize && s_min_extra_isize) { 11836dd4ee7cSKalpak Shah tried_min_extra_isize++; 11846dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 11856dd4ee7cSKalpak Shah brelse(bh); 11866dd4ee7cSKalpak Shah goto retry; 11876dd4ee7cSKalpak Shah } 11886dd4ee7cSKalpak Shah error = -1; 11896dd4ee7cSKalpak Shah goto cleanup; 11906dd4ee7cSKalpak Shah } 11916dd4ee7cSKalpak Shah } else { 11926dd4ee7cSKalpak Shah free = inode->i_sb->s_blocksize; 11936dd4ee7cSKalpak Shah } 11946dd4ee7cSKalpak Shah 11956dd4ee7cSKalpak Shah while (new_extra_isize > 0) { 11966dd4ee7cSKalpak Shah size_t offs, size, entry_size; 11976dd4ee7cSKalpak Shah struct ext4_xattr_entry *small_entry = NULL; 11986dd4ee7cSKalpak Shah struct ext4_xattr_info i = { 11996dd4ee7cSKalpak Shah .value = NULL, 12006dd4ee7cSKalpak Shah .value_len = 0, 12016dd4ee7cSKalpak Shah }; 12026dd4ee7cSKalpak Shah unsigned int total_size; /* EA entry size + value size */ 12036dd4ee7cSKalpak Shah unsigned int shift_bytes; /* No. of bytes to shift EAs by? */ 12046dd4ee7cSKalpak Shah unsigned int min_total_size = ~0U; 12056dd4ee7cSKalpak Shah 12066dd4ee7cSKalpak Shah is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); 12076dd4ee7cSKalpak Shah bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); 12086dd4ee7cSKalpak Shah if (!is || !bs) { 12096dd4ee7cSKalpak Shah error = -ENOMEM; 12106dd4ee7cSKalpak Shah goto cleanup; 12116dd4ee7cSKalpak Shah } 12126dd4ee7cSKalpak Shah 12136dd4ee7cSKalpak Shah is->s.not_found = -ENODATA; 12146dd4ee7cSKalpak Shah bs->s.not_found = -ENODATA; 12156dd4ee7cSKalpak Shah is->iloc.bh = NULL; 12166dd4ee7cSKalpak Shah bs->bh = NULL; 12176dd4ee7cSKalpak Shah 12186dd4ee7cSKalpak Shah last = IFIRST(header); 12196dd4ee7cSKalpak Shah /* Find the entry best suited to be pushed into EA block */ 12206dd4ee7cSKalpak Shah entry = NULL; 12216dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 12226dd4ee7cSKalpak Shah total_size = 12236dd4ee7cSKalpak Shah EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + 12246dd4ee7cSKalpak Shah EXT4_XATTR_LEN(last->e_name_len); 12256dd4ee7cSKalpak Shah if (total_size <= free && total_size < min_total_size) { 12266dd4ee7cSKalpak Shah if (total_size < new_extra_isize) { 12276dd4ee7cSKalpak Shah small_entry = last; 12286dd4ee7cSKalpak Shah } else { 12296dd4ee7cSKalpak Shah entry = last; 12306dd4ee7cSKalpak Shah min_total_size = total_size; 12316dd4ee7cSKalpak Shah } 12326dd4ee7cSKalpak Shah } 12336dd4ee7cSKalpak Shah } 12346dd4ee7cSKalpak Shah 12356dd4ee7cSKalpak Shah if (entry == NULL) { 12366dd4ee7cSKalpak Shah if (small_entry) { 12376dd4ee7cSKalpak Shah entry = small_entry; 12386dd4ee7cSKalpak Shah } else { 12396dd4ee7cSKalpak Shah if (!tried_min_extra_isize && 12406dd4ee7cSKalpak Shah s_min_extra_isize) { 12416dd4ee7cSKalpak Shah tried_min_extra_isize++; 12426dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 12436dd4ee7cSKalpak Shah goto retry; 12446dd4ee7cSKalpak Shah } 12456dd4ee7cSKalpak Shah error = -1; 12466dd4ee7cSKalpak Shah goto cleanup; 12476dd4ee7cSKalpak Shah } 12486dd4ee7cSKalpak Shah } 12496dd4ee7cSKalpak Shah offs = le16_to_cpu(entry->e_value_offs); 12506dd4ee7cSKalpak Shah size = le32_to_cpu(entry->e_value_size); 12516dd4ee7cSKalpak Shah entry_size = EXT4_XATTR_LEN(entry->e_name_len); 12526dd4ee7cSKalpak Shah i.name_index = entry->e_name_index, 12536dd4ee7cSKalpak Shah buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS); 12546dd4ee7cSKalpak Shah b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); 12556dd4ee7cSKalpak Shah if (!buffer || !b_entry_name) { 12566dd4ee7cSKalpak Shah error = -ENOMEM; 12576dd4ee7cSKalpak Shah goto cleanup; 12586dd4ee7cSKalpak Shah } 12596dd4ee7cSKalpak Shah /* Save the entry name and the entry value */ 12606dd4ee7cSKalpak Shah memcpy(buffer, (void *)IFIRST(header) + offs, 12616dd4ee7cSKalpak Shah EXT4_XATTR_SIZE(size)); 12626dd4ee7cSKalpak Shah memcpy(b_entry_name, entry->e_name, entry->e_name_len); 12636dd4ee7cSKalpak Shah b_entry_name[entry->e_name_len] = '\0'; 12646dd4ee7cSKalpak Shah i.name = b_entry_name; 12656dd4ee7cSKalpak Shah 12666dd4ee7cSKalpak Shah error = ext4_get_inode_loc(inode, &is->iloc); 12676dd4ee7cSKalpak Shah if (error) 12686dd4ee7cSKalpak Shah goto cleanup; 12696dd4ee7cSKalpak Shah 12706dd4ee7cSKalpak Shah error = ext4_xattr_ibody_find(inode, &i, is); 12716dd4ee7cSKalpak Shah if (error) 12726dd4ee7cSKalpak Shah goto cleanup; 12736dd4ee7cSKalpak Shah 12746dd4ee7cSKalpak Shah /* Remove the chosen entry from the inode */ 12756dd4ee7cSKalpak Shah error = ext4_xattr_ibody_set(handle, inode, &i, is); 12766dd4ee7cSKalpak Shah 12776dd4ee7cSKalpak Shah entry = IFIRST(header); 12786dd4ee7cSKalpak Shah if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize) 12796dd4ee7cSKalpak Shah shift_bytes = new_extra_isize; 12806dd4ee7cSKalpak Shah else 12816dd4ee7cSKalpak Shah shift_bytes = entry_size + size; 12826dd4ee7cSKalpak Shah /* Adjust the offsets and shift the remaining entries ahead */ 12836dd4ee7cSKalpak Shah ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize - 12846dd4ee7cSKalpak Shah shift_bytes, (void *)raw_inode + 12856dd4ee7cSKalpak Shah EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes, 12866dd4ee7cSKalpak Shah (void *)header, total_ino - entry_size, 12876dd4ee7cSKalpak Shah inode->i_sb->s_blocksize); 12886dd4ee7cSKalpak Shah 12896dd4ee7cSKalpak Shah extra_isize += shift_bytes; 12906dd4ee7cSKalpak Shah new_extra_isize -= shift_bytes; 12916dd4ee7cSKalpak Shah EXT4_I(inode)->i_extra_isize = extra_isize; 12926dd4ee7cSKalpak Shah 12936dd4ee7cSKalpak Shah i.name = b_entry_name; 12946dd4ee7cSKalpak Shah i.value = buffer; 1295*ac39849dSAneesh Kumar K.V i.value_len = size; 12966dd4ee7cSKalpak Shah error = ext4_xattr_block_find(inode, &i, bs); 12976dd4ee7cSKalpak Shah if (error) 12986dd4ee7cSKalpak Shah goto cleanup; 12996dd4ee7cSKalpak Shah 13006dd4ee7cSKalpak Shah /* Add entry which was removed from the inode into the block */ 13016dd4ee7cSKalpak Shah error = ext4_xattr_block_set(handle, inode, &i, bs); 13026dd4ee7cSKalpak Shah if (error) 13036dd4ee7cSKalpak Shah goto cleanup; 13046dd4ee7cSKalpak Shah kfree(b_entry_name); 13056dd4ee7cSKalpak Shah kfree(buffer); 13066dd4ee7cSKalpak Shah brelse(is->iloc.bh); 13076dd4ee7cSKalpak Shah kfree(is); 13086dd4ee7cSKalpak Shah kfree(bs); 13096dd4ee7cSKalpak Shah } 13106dd4ee7cSKalpak Shah brelse(bh); 13116dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 13126dd4ee7cSKalpak Shah return 0; 13136dd4ee7cSKalpak Shah 13146dd4ee7cSKalpak Shah cleanup: 13156dd4ee7cSKalpak Shah kfree(b_entry_name); 13166dd4ee7cSKalpak Shah kfree(buffer); 13176dd4ee7cSKalpak Shah if (is) 13186dd4ee7cSKalpak Shah brelse(is->iloc.bh); 13196dd4ee7cSKalpak Shah kfree(is); 13206dd4ee7cSKalpak Shah kfree(bs); 13216dd4ee7cSKalpak Shah brelse(bh); 13226dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 13236dd4ee7cSKalpak Shah return error; 13246dd4ee7cSKalpak Shah } 13256dd4ee7cSKalpak Shah 13266dd4ee7cSKalpak Shah 13276dd4ee7cSKalpak Shah 13286dd4ee7cSKalpak Shah /* 1329617ba13bSMingming Cao * ext4_xattr_delete_inode() 1330ac27a0ecSDave Kleikamp * 1331ac27a0ecSDave Kleikamp * Free extended attribute resources associated with this inode. This 1332ac27a0ecSDave Kleikamp * is called immediately before an inode is freed. We have exclusive 1333ac27a0ecSDave Kleikamp * access to the inode. 1334ac27a0ecSDave Kleikamp */ 1335ac27a0ecSDave Kleikamp void 1336617ba13bSMingming Cao ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) 1337ac27a0ecSDave Kleikamp { 1338ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 1339ac27a0ecSDave Kleikamp 1340617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 1341ac27a0ecSDave Kleikamp goto cleanup; 1342617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 1343ac27a0ecSDave Kleikamp if (!bh) { 1344617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 13452ae02107SMingming Cao "inode %lu: block %llu read error", inode->i_ino, 1346617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 1347ac27a0ecSDave Kleikamp goto cleanup; 1348ac27a0ecSDave Kleikamp } 1349617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 1350ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) { 1351617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 13522ae02107SMingming Cao "inode %lu: bad block %llu", inode->i_ino, 1353617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 1354ac27a0ecSDave Kleikamp goto cleanup; 1355ac27a0ecSDave Kleikamp } 1356617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bh); 1357617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = 0; 1358ac27a0ecSDave Kleikamp 1359ac27a0ecSDave Kleikamp cleanup: 1360ac27a0ecSDave Kleikamp brelse(bh); 1361ac27a0ecSDave Kleikamp } 1362ac27a0ecSDave Kleikamp 1363ac27a0ecSDave Kleikamp /* 1364617ba13bSMingming Cao * ext4_xattr_put_super() 1365ac27a0ecSDave Kleikamp * 1366ac27a0ecSDave Kleikamp * This is called when a file system is unmounted. 1367ac27a0ecSDave Kleikamp */ 1368ac27a0ecSDave Kleikamp void 1369617ba13bSMingming Cao ext4_xattr_put_super(struct super_block *sb) 1370ac27a0ecSDave Kleikamp { 1371ac27a0ecSDave Kleikamp mb_cache_shrink(sb->s_bdev); 1372ac27a0ecSDave Kleikamp } 1373ac27a0ecSDave Kleikamp 1374ac27a0ecSDave Kleikamp /* 1375617ba13bSMingming Cao * ext4_xattr_cache_insert() 1376ac27a0ecSDave Kleikamp * 1377ac27a0ecSDave Kleikamp * Create a new entry in the extended attribute cache, and insert 1378ac27a0ecSDave Kleikamp * it unless such an entry is already in the cache. 1379ac27a0ecSDave Kleikamp * 1380ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1381ac27a0ecSDave Kleikamp */ 1382ac27a0ecSDave Kleikamp static void 1383617ba13bSMingming Cao ext4_xattr_cache_insert(struct buffer_head *bh) 1384ac27a0ecSDave Kleikamp { 1385ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(BHDR(bh)->h_hash); 1386ac27a0ecSDave Kleikamp struct mb_cache_entry *ce; 1387ac27a0ecSDave Kleikamp int error; 1388ac27a0ecSDave Kleikamp 1389617ba13bSMingming Cao ce = mb_cache_entry_alloc(ext4_xattr_cache); 1390ac27a0ecSDave Kleikamp if (!ce) { 1391ac27a0ecSDave Kleikamp ea_bdebug(bh, "out of memory"); 1392ac27a0ecSDave Kleikamp return; 1393ac27a0ecSDave Kleikamp } 1394ac27a0ecSDave Kleikamp error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash); 1395ac27a0ecSDave Kleikamp if (error) { 1396ac27a0ecSDave Kleikamp mb_cache_entry_free(ce); 1397ac27a0ecSDave Kleikamp if (error == -EBUSY) { 1398ac27a0ecSDave Kleikamp ea_bdebug(bh, "already in cache"); 1399ac27a0ecSDave Kleikamp error = 0; 1400ac27a0ecSDave Kleikamp } 1401ac27a0ecSDave Kleikamp } else { 1402ac27a0ecSDave Kleikamp ea_bdebug(bh, "inserting [%x]", (int)hash); 1403ac27a0ecSDave Kleikamp mb_cache_entry_release(ce); 1404ac27a0ecSDave Kleikamp } 1405ac27a0ecSDave Kleikamp } 1406ac27a0ecSDave Kleikamp 1407ac27a0ecSDave Kleikamp /* 1408617ba13bSMingming Cao * ext4_xattr_cmp() 1409ac27a0ecSDave Kleikamp * 1410ac27a0ecSDave Kleikamp * Compare two extended attribute blocks for equality. 1411ac27a0ecSDave Kleikamp * 1412ac27a0ecSDave Kleikamp * Returns 0 if the blocks are equal, 1 if they differ, and 1413ac27a0ecSDave Kleikamp * a negative error number on errors. 1414ac27a0ecSDave Kleikamp */ 1415ac27a0ecSDave Kleikamp static int 1416617ba13bSMingming Cao ext4_xattr_cmp(struct ext4_xattr_header *header1, 1417617ba13bSMingming Cao struct ext4_xattr_header *header2) 1418ac27a0ecSDave Kleikamp { 1419617ba13bSMingming Cao struct ext4_xattr_entry *entry1, *entry2; 1420ac27a0ecSDave Kleikamp 1421ac27a0ecSDave Kleikamp entry1 = ENTRY(header1+1); 1422ac27a0ecSDave Kleikamp entry2 = ENTRY(header2+1); 1423ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry1)) { 1424ac27a0ecSDave Kleikamp if (IS_LAST_ENTRY(entry2)) 1425ac27a0ecSDave Kleikamp return 1; 1426ac27a0ecSDave Kleikamp if (entry1->e_hash != entry2->e_hash || 1427ac27a0ecSDave Kleikamp entry1->e_name_index != entry2->e_name_index || 1428ac27a0ecSDave Kleikamp entry1->e_name_len != entry2->e_name_len || 1429ac27a0ecSDave Kleikamp entry1->e_value_size != entry2->e_value_size || 1430ac27a0ecSDave Kleikamp memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) 1431ac27a0ecSDave Kleikamp return 1; 1432ac27a0ecSDave Kleikamp if (entry1->e_value_block != 0 || entry2->e_value_block != 0) 1433ac27a0ecSDave Kleikamp return -EIO; 1434ac27a0ecSDave Kleikamp if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), 1435ac27a0ecSDave Kleikamp (char *)header2 + le16_to_cpu(entry2->e_value_offs), 1436ac27a0ecSDave Kleikamp le32_to_cpu(entry1->e_value_size))) 1437ac27a0ecSDave Kleikamp return 1; 1438ac27a0ecSDave Kleikamp 1439617ba13bSMingming Cao entry1 = EXT4_XATTR_NEXT(entry1); 1440617ba13bSMingming Cao entry2 = EXT4_XATTR_NEXT(entry2); 1441ac27a0ecSDave Kleikamp } 1442ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(entry2)) 1443ac27a0ecSDave Kleikamp return 1; 1444ac27a0ecSDave Kleikamp return 0; 1445ac27a0ecSDave Kleikamp } 1446ac27a0ecSDave Kleikamp 1447ac27a0ecSDave Kleikamp /* 1448617ba13bSMingming Cao * ext4_xattr_cache_find() 1449ac27a0ecSDave Kleikamp * 1450ac27a0ecSDave Kleikamp * Find an identical extended attribute block. 1451ac27a0ecSDave Kleikamp * 1452ac27a0ecSDave Kleikamp * Returns a pointer to the block found, or NULL if such a block was 1453ac27a0ecSDave Kleikamp * not found or an error occurred. 1454ac27a0ecSDave Kleikamp */ 1455ac27a0ecSDave Kleikamp static struct buffer_head * 1456617ba13bSMingming Cao ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, 1457ac27a0ecSDave Kleikamp struct mb_cache_entry **pce) 1458ac27a0ecSDave Kleikamp { 1459ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(header->h_hash); 1460ac27a0ecSDave Kleikamp struct mb_cache_entry *ce; 1461ac27a0ecSDave Kleikamp 1462ac27a0ecSDave Kleikamp if (!header->h_hash) 1463ac27a0ecSDave Kleikamp return NULL; /* never share */ 1464ac27a0ecSDave Kleikamp ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); 1465ac27a0ecSDave Kleikamp again: 1466617ba13bSMingming Cao ce = mb_cache_entry_find_first(ext4_xattr_cache, 0, 1467ac27a0ecSDave Kleikamp inode->i_sb->s_bdev, hash); 1468ac27a0ecSDave Kleikamp while (ce) { 1469ac27a0ecSDave Kleikamp struct buffer_head *bh; 1470ac27a0ecSDave Kleikamp 1471ac27a0ecSDave Kleikamp if (IS_ERR(ce)) { 1472ac27a0ecSDave Kleikamp if (PTR_ERR(ce) == -EAGAIN) 1473ac27a0ecSDave Kleikamp goto again; 1474ac27a0ecSDave Kleikamp break; 1475ac27a0ecSDave Kleikamp } 1476ac27a0ecSDave Kleikamp bh = sb_bread(inode->i_sb, ce->e_block); 1477ac27a0ecSDave Kleikamp if (!bh) { 1478617ba13bSMingming Cao ext4_error(inode->i_sb, __FUNCTION__, 1479ac27a0ecSDave Kleikamp "inode %lu: block %lu read error", 1480ac27a0ecSDave Kleikamp inode->i_ino, (unsigned long) ce->e_block); 1481ac27a0ecSDave Kleikamp } else if (le32_to_cpu(BHDR(bh)->h_refcount) >= 1482617ba13bSMingming Cao EXT4_XATTR_REFCOUNT_MAX) { 1483ac27a0ecSDave Kleikamp ea_idebug(inode, "block %lu refcount %d>=%d", 1484ac27a0ecSDave Kleikamp (unsigned long) ce->e_block, 1485ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount), 1486617ba13bSMingming Cao EXT4_XATTR_REFCOUNT_MAX); 1487617ba13bSMingming Cao } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { 1488ac27a0ecSDave Kleikamp *pce = ce; 1489ac27a0ecSDave Kleikamp return bh; 1490ac27a0ecSDave Kleikamp } 1491ac27a0ecSDave Kleikamp brelse(bh); 1492ac27a0ecSDave Kleikamp ce = mb_cache_entry_find_next(ce, 0, inode->i_sb->s_bdev, hash); 1493ac27a0ecSDave Kleikamp } 1494ac27a0ecSDave Kleikamp return NULL; 1495ac27a0ecSDave Kleikamp } 1496ac27a0ecSDave Kleikamp 1497ac27a0ecSDave Kleikamp #define NAME_HASH_SHIFT 5 1498ac27a0ecSDave Kleikamp #define VALUE_HASH_SHIFT 16 1499ac27a0ecSDave Kleikamp 1500ac27a0ecSDave Kleikamp /* 1501617ba13bSMingming Cao * ext4_xattr_hash_entry() 1502ac27a0ecSDave Kleikamp * 1503ac27a0ecSDave Kleikamp * Compute the hash of an extended attribute. 1504ac27a0ecSDave Kleikamp */ 1505617ba13bSMingming Cao static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, 1506617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1507ac27a0ecSDave Kleikamp { 1508ac27a0ecSDave Kleikamp __u32 hash = 0; 1509ac27a0ecSDave Kleikamp char *name = entry->e_name; 1510ac27a0ecSDave Kleikamp int n; 1511ac27a0ecSDave Kleikamp 1512ac27a0ecSDave Kleikamp for (n=0; n < entry->e_name_len; n++) { 1513ac27a0ecSDave Kleikamp hash = (hash << NAME_HASH_SHIFT) ^ 1514ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ 1515ac27a0ecSDave Kleikamp *name++; 1516ac27a0ecSDave Kleikamp } 1517ac27a0ecSDave Kleikamp 1518ac27a0ecSDave Kleikamp if (entry->e_value_block == 0 && entry->e_value_size != 0) { 1519ac27a0ecSDave Kleikamp __le32 *value = (__le32 *)((char *)header + 1520ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs)); 1521ac27a0ecSDave Kleikamp for (n = (le32_to_cpu(entry->e_value_size) + 1522617ba13bSMingming Cao EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { 1523ac27a0ecSDave Kleikamp hash = (hash << VALUE_HASH_SHIFT) ^ 1524ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ 1525ac27a0ecSDave Kleikamp le32_to_cpu(*value++); 1526ac27a0ecSDave Kleikamp } 1527ac27a0ecSDave Kleikamp } 1528ac27a0ecSDave Kleikamp entry->e_hash = cpu_to_le32(hash); 1529ac27a0ecSDave Kleikamp } 1530ac27a0ecSDave Kleikamp 1531ac27a0ecSDave Kleikamp #undef NAME_HASH_SHIFT 1532ac27a0ecSDave Kleikamp #undef VALUE_HASH_SHIFT 1533ac27a0ecSDave Kleikamp 1534ac27a0ecSDave Kleikamp #define BLOCK_HASH_SHIFT 16 1535ac27a0ecSDave Kleikamp 1536ac27a0ecSDave Kleikamp /* 1537617ba13bSMingming Cao * ext4_xattr_rehash() 1538ac27a0ecSDave Kleikamp * 1539ac27a0ecSDave Kleikamp * Re-compute the extended attribute hash value after an entry has changed. 1540ac27a0ecSDave Kleikamp */ 1541617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *header, 1542617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1543ac27a0ecSDave Kleikamp { 1544617ba13bSMingming Cao struct ext4_xattr_entry *here; 1545ac27a0ecSDave Kleikamp __u32 hash = 0; 1546ac27a0ecSDave Kleikamp 1547617ba13bSMingming Cao ext4_xattr_hash_entry(header, entry); 1548ac27a0ecSDave Kleikamp here = ENTRY(header+1); 1549ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(here)) { 1550ac27a0ecSDave Kleikamp if (!here->e_hash) { 1551ac27a0ecSDave Kleikamp /* Block is not shared if an entry's hash value == 0 */ 1552ac27a0ecSDave Kleikamp hash = 0; 1553ac27a0ecSDave Kleikamp break; 1554ac27a0ecSDave Kleikamp } 1555ac27a0ecSDave Kleikamp hash = (hash << BLOCK_HASH_SHIFT) ^ 1556ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ 1557ac27a0ecSDave Kleikamp le32_to_cpu(here->e_hash); 1558617ba13bSMingming Cao here = EXT4_XATTR_NEXT(here); 1559ac27a0ecSDave Kleikamp } 1560ac27a0ecSDave Kleikamp header->h_hash = cpu_to_le32(hash); 1561ac27a0ecSDave Kleikamp } 1562ac27a0ecSDave Kleikamp 1563ac27a0ecSDave Kleikamp #undef BLOCK_HASH_SHIFT 1564ac27a0ecSDave Kleikamp 1565ac27a0ecSDave Kleikamp int __init 1566617ba13bSMingming Cao init_ext4_xattr(void) 1567ac27a0ecSDave Kleikamp { 1568617ba13bSMingming Cao ext4_xattr_cache = mb_cache_create("ext4_xattr", NULL, 1569ac27a0ecSDave Kleikamp sizeof(struct mb_cache_entry) + 1570ac27a0ecSDave Kleikamp sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]), 1, 6); 1571617ba13bSMingming Cao if (!ext4_xattr_cache) 1572ac27a0ecSDave Kleikamp return -ENOMEM; 1573ac27a0ecSDave Kleikamp return 0; 1574ac27a0ecSDave Kleikamp } 1575ac27a0ecSDave Kleikamp 1576ac27a0ecSDave Kleikamp void 1577617ba13bSMingming Cao exit_ext4_xattr(void) 1578ac27a0ecSDave Kleikamp { 1579617ba13bSMingming Cao if (ext4_xattr_cache) 1580617ba13bSMingming Cao mb_cache_destroy(ext4_xattr_cache); 1581617ba13bSMingming Cao ext4_xattr_cache = NULL; 1582ac27a0ecSDave Kleikamp } 1583