fs/f2fs/xattr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * fs/f2fs/xattr.c
   4  *
   5  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   6  *             http://www.samsung.com/
   7  *
   8  * Portions of this code from linux/fs/ext2/xattr.c
   9  *
  10  * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
  11  *
  12  * Fix by Harrison Xing <harrison@mountainviewdata.com>.
  13  * Extended attributes for symlinks and special files added per
  14  *  suggestion of Luka Renko <luka.renko@hermes.si>.
  15  * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
  16  *  Red Hat Inc.
  17  */
  18 #include <linux/rwsem.h>
  19 #include <linux/f2fs_fs.h>
  20 #include <linux/security.h>
  21 #include <linux/posix_acl_xattr.h>
  22 #include "f2fs.h"
  23 #include "xattr.h"
  24
  25 static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
  26                 struct dentry *unused, struct inode *inode,
  27                 const char *name, void *buffer, size_t size)
  28 {
  29         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  30
  31         switch (handler->flags) {
  32         case F2FS_XATTR_INDEX_USER:
  33                 if (!test_opt(sbi, XATTR_USER))
  34                         return -EOPNOTSUPP;
  35                 break;
  36         case F2FS_XATTR_INDEX_TRUSTED:
  37         case F2FS_XATTR_INDEX_SECURITY:
  38                 break;
  39         default:
  40                 return -EINVAL;
  41         }
  42         return f2fs_getxattr(inode, handler->flags, name,
  43                              buffer, size, NULL);
  44 }
  45
  46 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
  47                 struct dentry *unused, struct inode *inode,
  48                 const char *name, const void *value,
  49                 size_t size, int flags)
  50 {
  51         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  52
  53         switch (handler->flags) {
  54         case F2FS_XATTR_INDEX_USER:
  55                 if (!test_opt(sbi, XATTR_USER))
  56                         return -EOPNOTSUPP;
  57                 break;
  58         case F2FS_XATTR_INDEX_TRUSTED:
  59         case F2FS_XATTR_INDEX_SECURITY:
  60                 break;
  61         default:
  62                 return -EINVAL;
  63         }
  64         return f2fs_setxattr(inode, handler->flags, name,
  65                                         value, size, NULL, flags);
  66 }
  67
  68 static bool f2fs_xattr_user_list(struct dentry *dentry)
  69 {
  70         struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
  71
  72         return test_opt(sbi, XATTR_USER);
  73 }
  74
  75 static bool f2fs_xattr_trusted_list(struct dentry *dentry)
  76 {
  77         return capable(CAP_SYS_ADMIN);
  78 }
  79
  80 static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
  81                 struct dentry *unused, struct inode *inode,
  82                 const char *name, void *buffer, size_t size)
  83 {
  84         if (buffer)
  85                 *((char *)buffer) = F2FS_I(inode)->i_advise;
  86         return sizeof(char);
  87 }
  88
  89 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
  90                 struct dentry *unused, struct inode *inode,
  91                 const char *name, const void *value,
  92                 size_t size, int flags)
  93 {
  94         unsigned char old_advise = F2FS_I(inode)->i_advise;
  95         unsigned char new_advise;
  96
  97         if (!inode_owner_or_capable(inode))
  98                 return -EPERM;
  99         if (value == NULL)
 100                 return -EINVAL;
 101
 102         new_advise = *(char *)value;
 103         if (new_advise & ~FADVISE_MODIFIABLE_BITS)
 104                 return -EINVAL;
 105
 106         new_advise = new_advise & FADVISE_MODIFIABLE_BITS;
 107         new_advise |= old_advise & ~FADVISE_MODIFIABLE_BITS;
 108
 109         F2FS_I(inode)->i_advise = new_advise;
 110         f2fs_mark_inode_dirty_sync(inode, true);
 111         return 0;
 112 }
 113
 114 #ifdef CONFIG_F2FS_FS_SECURITY
 115 static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
 116                 void *page)
 117 {
 118         const struct xattr *xattr;
 119         int err = 0;
 120
 121         for (xattr = xattr_array; xattr->name != NULL; xattr++) {
 122                 err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
 123                                 xattr->name, xattr->value,
 124                                 xattr->value_len, (struct page *)page, 0);
 125                 if (err < 0)
 126                         break;
 127         }
 128         return err;
 129 }
 130
 131 int f2fs_init_security(struct inode *inode, struct inode *dir,
 132                                 const struct qstr *qstr, struct page *ipage)
 133 {
 134         return security_inode_init_security(inode, dir, qstr,
 135                                 &f2fs_initxattrs, ipage);
 136 }
 137 #endif
 138
 139 const struct xattr_handler f2fs_xattr_user_handler = {
 140         .prefix = XATTR_USER_PREFIX,
 141         .flags  = F2FS_XATTR_INDEX_USER,
 142         .list   = f2fs_xattr_user_list,
 143         .get    = f2fs_xattr_generic_get,
 144         .set    = f2fs_xattr_generic_set,
 145 };
 146
 147 const struct xattr_handler f2fs_xattr_trusted_handler = {
 148         .prefix = XATTR_TRUSTED_PREFIX,
 149         .flags  = F2FS_XATTR_INDEX_TRUSTED,
 150         .list   = f2fs_xattr_trusted_list,
 151         .get    = f2fs_xattr_generic_get,
 152         .set    = f2fs_xattr_generic_set,
 153 };
 154
 155 const struct xattr_handler f2fs_xattr_advise_handler = {
 156         .name   = F2FS_SYSTEM_ADVISE_NAME,
 157         .flags  = F2FS_XATTR_INDEX_ADVISE,
 158         .get    = f2fs_xattr_advise_get,
 159         .set    = f2fs_xattr_advise_set,
 160 };
 161
 162 const struct xattr_handler f2fs_xattr_security_handler = {
 163         .prefix = XATTR_SECURITY_PREFIX,
 164         .flags  = F2FS_XATTR_INDEX_SECURITY,
 165         .get    = f2fs_xattr_generic_get,
 166         .set    = f2fs_xattr_generic_set,
 167 };
 168
 169 static const struct xattr_handler *f2fs_xattr_handler_map[] = {
 170         [F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
 171 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 172         [F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
 173         [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
 174 #endif
 175         [F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
 176 #ifdef CONFIG_F2FS_FS_SECURITY
 177         [F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
 178 #endif
 179         [F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
 180 };
 181
 182 const struct xattr_handler *f2fs_xattr_handlers[] = {
 183         &f2fs_xattr_user_handler,
 184 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 185         &posix_acl_access_xattr_handler,
 186         &posix_acl_default_xattr_handler,
 187 #endif
 188         &f2fs_xattr_trusted_handler,
 189 #ifdef CONFIG_F2FS_FS_SECURITY
 190         &f2fs_xattr_security_handler,
 191 #endif
 192         &f2fs_xattr_advise_handler,
 193         NULL,
 194 };
 195
 196 static inline const struct xattr_handler *f2fs_xattr_handler(int index)
 197 {
 198         const struct xattr_handler *handler = NULL;
 199
 200         if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
 201                 handler = f2fs_xattr_handler_map[index];
 202         return handler;
 203 }
 204
 205 static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
 206                                 void *last_base_addr, int index,
 207                                 size_t len, const char *name)
 208 {
 209         struct f2fs_xattr_entry *entry;
 210
 211         list_for_each_xattr(entry, base_addr) {
 212                 if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
 213                         (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr)
 214                         return NULL;
 215
 216                 if (entry->e_name_index != index)
 217                         continue;
 218                 if (entry->e_name_len != len)
 219                         continue;
 220                 if (!memcmp(entry->e_name, name, len))
 221                         break;
 222         }
 223         return entry;
 224 }
 225
 226 static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode,
 227                                 void *base_addr, void **last_addr, int index,
 228                                 size_t len, const char *name)
 229 {
 230         struct f2fs_xattr_entry *entry;
 231         unsigned int inline_size = inline_xattr_size(inode);
 232         void *max_addr = base_addr + inline_size;
 233
 234         list_for_each_xattr(entry, base_addr) {
 235                 if ((void *)entry + sizeof(__u32) > max_addr ||
 236                         (void *)XATTR_NEXT_ENTRY(entry) > max_addr) {
 237                         *last_addr = entry;
 238                         return NULL;
 239                 }
 240                 if (entry->e_name_index != index)
 241                         continue;
 242                 if (entry->e_name_len != len)
 243                         continue;
 244                 if (!memcmp(entry->e_name, name, len))
 245                         break;
 246         }
 247
 248         /* inline xattr header or entry across max inline xattr size */
 249         if (IS_XATTR_LAST_ENTRY(entry) &&
 250                 (void *)entry + sizeof(__u32) > max_addr) {
 251                 *last_addr = entry;
 252                 return NULL;
 253         }
 254         return entry;
 255 }
 256
 257 static int read_inline_xattr(struct inode *inode, struct page *ipage,
 258                                                         void *txattr_addr)
 259 {
 260         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 261         unsigned int inline_size = inline_xattr_size(inode);
 262         struct page *page = NULL;
 263         void *inline_addr;
 264
 265         if (ipage) {
 266                 inline_addr = inline_xattr_addr(inode, ipage);
 267         } else {
 268                 page = f2fs_get_node_page(sbi, inode->i_ino);
 269                 if (IS_ERR(page))
 270                         return PTR_ERR(page);
 271
 272                 inline_addr = inline_xattr_addr(inode, page);
 273         }
 274         memcpy(txattr_addr, inline_addr, inline_size);
 275         f2fs_put_page(page, 1);
 276
 277         return 0;
 278 }
 279
 280 static int read_xattr_block(struct inode *inode, void *txattr_addr)
 281 {
 282         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 283         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 284         unsigned int inline_size = inline_xattr_size(inode);
 285         struct page *xpage;
 286         void *xattr_addr;
 287
 288         /* The inode already has an extended attribute block. */
 289         xpage = f2fs_get_node_page(sbi, xnid);
 290         if (IS_ERR(xpage))
 291                 return PTR_ERR(xpage);
 292
 293         xattr_addr = page_address(xpage);
 294         memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE);
 295         f2fs_put_page(xpage, 1);
 296
 297         return 0;
 298 }
 299
 300 static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
 301                                 unsigned int index, unsigned int len,
 302                                 const char *name, struct f2fs_xattr_entry **xe,
 303                                 void **base_addr, int *base_size)
 304 {
 305         void *cur_addr, *txattr_addr, *last_txattr_addr;
 306         void *last_addr = NULL;
 307         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 308         unsigned int inline_size = inline_xattr_size(inode);
 309         int err = 0;
 310
 311         if (!xnid && !inline_size)
 312                 return -ENODATA;
 313
 314         *base_size = XATTR_SIZE(xnid, inode) + XATTR_PADDING_SIZE;
 315         txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode), *base_size, GFP_NOFS);
 316         if (!txattr_addr)
 317                 return -ENOMEM;
 318
 319         last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(xnid, inode);
 320
 321         /* read from inline xattr */
 322         if (inline_size) {
 323                 err = read_inline_xattr(inode, ipage, txattr_addr);
 324                 if (err)
 325                         goto out;
 326
 327                 *xe = __find_inline_xattr(inode, txattr_addr, &last_addr,
 328                                                 index, len, name);
 329                 if (*xe) {
 330                         *base_size = inline_size;
 331                         goto check;
 332                 }
 333         }
 334
 335         /* read from xattr node block */
 336         if (xnid) {
 337                 err = read_xattr_block(inode, txattr_addr);
 338                 if (err)
 339                         goto out;
 340         }
 341
 342         if (last_addr)
 343                 cur_addr = XATTR_HDR(last_addr) - 1;
 344         else
 345                 cur_addr = txattr_addr;
 346
 347         *xe = __find_xattr(cur_addr, last_txattr_addr, index, len, name);
 348         if (!*xe) {
 349                 err = -EFAULT;
 350                 goto out;
 351         }
 352 check:
 353         if (IS_XATTR_LAST_ENTRY(*xe)) {
 354                 err = -ENODATA;
 355                 goto out;
 356         }
 357
 358         *base_addr = txattr_addr;
 359         return 0;
 360 out:
 361         kvfree(txattr_addr);
 362         return err;
 363 }
 364
 365 static int read_all_xattrs(struct inode *inode, struct page *ipage,
 366                                                         void **base_addr)
 367 {
 368         struct f2fs_xattr_header *header;
 369         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 370         unsigned int size = VALID_XATTR_BLOCK_SIZE;
 371         unsigned int inline_size = inline_xattr_size(inode);
 372         void *txattr_addr;
 373         int err;
 374
 375         txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode),
 376                         inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS);
 377         if (!txattr_addr)
 378                 return -ENOMEM;
 379
 380         /* read from inline xattr */
 381         if (inline_size) {
 382                 err = read_inline_xattr(inode, ipage, txattr_addr);
 383                 if (err)
 384                         goto fail;
 385         }
 386
 387         /* read from xattr node block */
 388         if (xnid) {
 389                 err = read_xattr_block(inode, txattr_addr);
 390                 if (err)
 391                         goto fail;
 392         }
 393
 394         header = XATTR_HDR(txattr_addr);
 395
 396         /* never been allocated xattrs */
 397         if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
 398                 header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
 399                 header->h_refcount = cpu_to_le32(1);
 400         }
 401         *base_addr = txattr_addr;
 402         return 0;
 403 fail:
 404         kvfree(txattr_addr);
 405         return err;
 406 }
 407
 408 static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
 409                                 void *txattr_addr, struct page *ipage)
 410 {
 411         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 412         size_t inline_size = inline_xattr_size(inode);
 413         struct page *in_page = NULL;
 414         void *xattr_addr;
 415         void *inline_addr = NULL;
 416         struct page *xpage;
 417         nid_t new_nid = 0;
 418         int err = 0;
 419
 420         if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
 421                 if (!f2fs_alloc_nid(sbi, &new_nid))
 422                         return -ENOSPC;
 423
 424         /* write to inline xattr */
 425         if (inline_size) {
 426                 if (ipage) {
 427                         inline_addr = inline_xattr_addr(inode, ipage);
 428                 } else {
 429                         in_page = f2fs_get_node_page(sbi, inode->i_ino);
 430                         if (IS_ERR(in_page)) {
 431                                 f2fs_alloc_nid_failed(sbi, new_nid);
 432                                 return PTR_ERR(in_page);
 433                         }
 434                         inline_addr = inline_xattr_addr(inode, in_page);
 435                 }
 436
 437                 f2fs_wait_on_page_writeback(ipage ? ipage : in_page,
 438                                                         NODE, true, true);
 439                 /* no need to use xattr node block */
 440                 if (hsize <= inline_size) {
 441                         err = f2fs_truncate_xattr_node(inode);
 442                         f2fs_alloc_nid_failed(sbi, new_nid);
 443                         if (err) {
 444                                 f2fs_put_page(in_page, 1);
 445                                 return err;
 446                         }
 447                         memcpy(inline_addr, txattr_addr, inline_size);
 448                         set_page_dirty(ipage ? ipage : in_page);
 449                         goto in_page_out;
 450                 }
 451         }
 452
 453         /* write to xattr node block */
 454         if (F2FS_I(inode)->i_xattr_nid) {
 455                 xpage = f2fs_get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
 456                 if (IS_ERR(xpage)) {
 457                         err = PTR_ERR(xpage);
 458                         f2fs_alloc_nid_failed(sbi, new_nid);
 459                         goto in_page_out;
 460                 }
 461                 f2fs_bug_on(sbi, new_nid);
 462                 f2fs_wait_on_page_writeback(xpage, NODE, true, true);
 463         } else {
 464                 struct dnode_of_data dn;
 465                 set_new_dnode(&dn, inode, NULL, NULL, new_nid);
 466                 xpage = f2fs_new_node_page(&dn, XATTR_NODE_OFFSET);
 467                 if (IS_ERR(xpage)) {
 468                         err = PTR_ERR(xpage);
 469                         f2fs_alloc_nid_failed(sbi, new_nid);
 470                         goto in_page_out;
 471                 }
 472                 f2fs_alloc_nid_done(sbi, new_nid);
 473         }
 474         xattr_addr = page_address(xpage);
 475
 476         if (inline_size)
 477                 memcpy(inline_addr, txattr_addr, inline_size);
 478         memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
 479
 480         if (inline_size)
 481                 set_page_dirty(ipage ? ipage : in_page);
 482         set_page_dirty(xpage);
 483
 484         f2fs_put_page(xpage, 1);
 485 in_page_out:
 486         f2fs_put_page(in_page, 1);
 487         return err;
 488 }
 489
 490 int f2fs_getxattr(struct inode *inode, int index, const char *name,
 491                 void *buffer, size_t buffer_size, struct page *ipage)
 492 {
 493         struct f2fs_xattr_entry *entry = NULL;
 494         int error = 0;
 495         unsigned int size, len;
 496         void *base_addr = NULL;
 497         int base_size;
 498
 499         if (name == NULL)
 500                 return -EINVAL;
 501
 502         len = strlen(name);
 503         if (len > F2FS_NAME_LEN)
 504                 return -ERANGE;
 505
 506         down_read(&F2FS_I(inode)->i_xattr_sem);
 507         error = lookup_all_xattrs(inode, ipage, index, len, name,
 508                                 &entry, &base_addr, &base_size);
 509         up_read(&F2FS_I(inode)->i_xattr_sem);
 510         if (error)
 511                 return error;
 512
 513         size = le16_to_cpu(entry->e_value_size);
 514
 515         if (buffer && size > buffer_size) {
 516                 error = -ERANGE;
 517                 goto out;
 518         }
 519
 520         if (buffer) {
 521                 char *pval = entry->e_name + entry->e_name_len;
 522
 523                 if (base_size - (pval - (char *)base_addr) < size) {
 524                         error = -ERANGE;
 525                         goto out;
 526                 }
 527                 memcpy(buffer, pval, size);
 528         }
 529         error = size;
 530 out:
 531         kvfree(base_addr);
 532         return error;
 533 }
 534
 535 ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
 536 {
 537         struct inode *inode = d_inode(dentry);
 538         struct f2fs_xattr_entry *entry;
 539         void *base_addr;
 540         int error = 0;
 541         size_t rest = buffer_size;
 542
 543         down_read(&F2FS_I(inode)->i_xattr_sem);
 544         error = read_all_xattrs(inode, NULL, &base_addr);
 545         up_read(&F2FS_I(inode)->i_xattr_sem);
 546         if (error)
 547                 return error;
 548
 549         list_for_each_xattr(entry, base_addr) {
 550                 const struct xattr_handler *handler =
 551                         f2fs_xattr_handler(entry->e_name_index);
 552                 const char *prefix;
 553                 size_t prefix_len;
 554                 size_t size;
 555
 556                 if (!handler || (handler->list && !handler->list(dentry)))
 557                         continue;
 558
 559                 prefix = xattr_prefix(handler);
 560                 prefix_len = strlen(prefix);
 561                 size = prefix_len + entry->e_name_len + 1;
 562                 if (buffer) {
 563                         if (size > rest) {
 564                                 error = -ERANGE;
 565                                 goto cleanup;
 566                         }
 567                         memcpy(buffer, prefix, prefix_len);
 568                         buffer += prefix_len;
 569                         memcpy(buffer, entry->e_name, entry->e_name_len);
 570                         buffer += entry->e_name_len;
 571                         *buffer++ = 0;
 572                 }
 573                 rest -= size;
 574         }
 575         error = buffer_size - rest;
 576 cleanup:
 577         kvfree(base_addr);
 578         return error;
 579 }
 580
 581 static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry,
 582                                         const void *value, size_t size)
 583 {
 584         void *pval = entry->e_name + entry->e_name_len;
 585
 586         return (le16_to_cpu(entry->e_value_size) == size) &&
 587                                         !memcmp(pval, value, size);
 588 }
 589
 590 static int __f2fs_setxattr(struct inode *inode, int index,
 591                         const char *name, const void *value, size_t size,
 592                         struct page *ipage, int flags)
 593 {
 594         struct f2fs_xattr_entry *here, *last;
 595         void *base_addr, *last_base_addr;
 596         nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 597         int found, newsize;
 598         size_t len;
 599         __u32 new_hsize;
 600         int error = 0;
 601
 602         if (name == NULL)
 603                 return -EINVAL;
 604
 605         if (value == NULL)
 606                 size = 0;
 607
 608         len = strlen(name);
 609
 610         if (len > F2FS_NAME_LEN)
 611                 return -ERANGE;
 612
 613         if (size > MAX_VALUE_LEN(inode))
 614                 return -E2BIG;
 615
 616         error = read_all_xattrs(inode, ipage, &base_addr);
 617         if (error)
 618                 return error;
 619
 620         last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode);
 621
 622         /* find entry with wanted name. */
 623         here = __find_xattr(base_addr, last_base_addr, index, len, name);
 624         if (!here) {
 625                 error = -EFAULT;
 626                 goto exit;
 627         }
 628
 629         found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
 630
 631         if (found) {
 632                 if ((flags & XATTR_CREATE)) {
 633                         error = -EEXIST;
 634                         goto exit;
 635                 }
 636
 637                 if (value && f2fs_xattr_value_same(here, value, size))
 638                         goto exit;
 639         } else if ((flags & XATTR_REPLACE)) {
 640                 error = -ENODATA;
 641                 goto exit;
 642         }
 643
 644         last = here;
 645         while (!IS_XATTR_LAST_ENTRY(last))
 646                 last = XATTR_NEXT_ENTRY(last);
 647
 648         newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
 649
 650         /* 1. Check space */
 651         if (value) {
 652                 int free;
 653                 /*
 654                  * If value is NULL, it is remove operation.
 655                  * In case of update operation, we calculate free.
 656                  */
 657                 free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
 658                 if (found)
 659                         free = free + ENTRY_SIZE(here);
 660
 661                 if (unlikely(free < newsize)) {
 662                         error = -E2BIG;
 663                         goto exit;
 664                 }
 665         }
 666
 667         /* 2. Remove old entry */
 668         if (found) {
 669                 /*
 670                  * If entry is found, remove old entry.
 671                  * If not found, remove operation is not needed.
 672                  */
 673                 struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
 674                 int oldsize = ENTRY_SIZE(here);
 675
 676                 memmove(here, next, (char *)last - (char *)next);
 677                 last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
 678                 memset(last, 0, oldsize);
 679         }
 680
 681         new_hsize = (char *)last - (char *)base_addr;
 682
 683         /* 3. Write new entry */
 684         if (value) {
 685                 char *pval;
 686                 /*
 687                  * Before we come here, old entry is removed.
 688                  * We just write new entry.
 689                  */
 690                 last->e_name_index = index;
 691                 last->e_name_len = len;
 692                 memcpy(last->e_name, name, len);
 693                 pval = last->e_name + len;
 694                 memcpy(pval, value, size);
 695                 last->e_value_size = cpu_to_le16(size);
 696                 new_hsize += newsize;
 697         }
 698
 699         error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
 700         if (error)
 701                 goto exit;
 702
 703         if (is_inode_flag_set(inode, FI_ACL_MODE)) {
 704                 inode->i_mode = F2FS_I(inode)->i_acl_mode;
 705                 inode->i_ctime = current_time(inode);
 706                 clear_inode_flag(inode, FI_ACL_MODE);
 707         }
 708         if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
 709                         !strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
 710                 f2fs_set_encrypted_inode(inode);
 711         f2fs_mark_inode_dirty_sync(inode, true);
 712         if (!error && S_ISDIR(inode->i_mode))
 713                 set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP);
 714 exit:
 715         kvfree(base_addr);
 716         return error;
 717 }
 718
 719 int f2fs_setxattr(struct inode *inode, int index, const char *name,
 720                                 const void *value, size_t size,
 721                                 struct page *ipage, int flags)
 722 {
 723         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 724         int err;
 725
 726         err = dquot_initialize(inode);
 727         if (err)
 728                 return err;
 729
 730         /* this case is only from f2fs_init_inode_metadata */
 731         if (ipage)
 732                 return __f2fs_setxattr(inode, index, name, value,
 733                                                 size, ipage, flags);
 734         f2fs_balance_fs(sbi, true);
 735
 736         f2fs_lock_op(sbi);
 737         /* protect xattr_ver */
 738         down_write(&F2FS_I(inode)->i_sem);
 739         down_write(&F2FS_I(inode)->i_xattr_sem);
 740         err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
 741         up_write(&F2FS_I(inode)->i_xattr_sem);
 742         up_write(&F2FS_I(inode)->i_sem);
 743         f2fs_unlock_op(sbi);
 744
 745         f2fs_update_time(sbi, REQ_TIME);
 746         return err;
 747 }