1 #include <linux/capability.h>
3 #include <linux/posix_acl.h>
4 #include <linux/reiserfs_fs.h>
5 #include <linux/errno.h>
6 #include <linux/pagemap.h>
7 #include <linux/xattr.h>
8 #include <linux/slab.h>
9 #include <linux/posix_acl_xattr.h>
10 #include <linux/reiserfs_xattr.h>
11 #include <linux/reiserfs_acl.h>
12 #include <asm/uaccess.h>
14 static int reiserfs_set_acl(struct reiserfs_transaction_handle *th,
15 struct inode *inode, int type,
16 struct posix_acl *acl);
19 posix_acl_set(struct dentry *dentry, const char *name, const void *value,
20 size_t size, int flags, int type)
22 struct inode *inode = dentry->d_inode;
23 struct posix_acl *acl;
25 struct reiserfs_transaction_handle th;
26 size_t jcreate_blocks;
27 if (!reiserfs_posixacl(inode->i_sb))
29 if (!inode_owner_or_capable(inode))
33 acl = posix_acl_from_xattr(value, size);
37 error = posix_acl_valid(acl);
44 /* Pessimism: We can't assume that anything from the xattr root up
45 * has been created. */
47 jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
48 reiserfs_xattr_nblocks(inode, size) * 2;
50 reiserfs_write_lock(inode->i_sb);
51 error = journal_begin(&th, inode->i_sb, jcreate_blocks);
53 error = reiserfs_set_acl(&th, inode, type, acl);
54 error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
58 reiserfs_write_unlock(inode->i_sb);
61 posix_acl_release(acl);
66 posix_acl_get(struct dentry *dentry, const char *name, void *buffer,
67 size_t size, int type)
69 struct posix_acl *acl;
72 if (!reiserfs_posixacl(dentry->d_sb))
75 acl = reiserfs_get_acl(dentry->d_inode, type);
80 error = posix_acl_to_xattr(acl, buffer, size);
81 posix_acl_release(acl);
87 * Convert from filesystem to in-memory representation.
89 static struct posix_acl *posix_acl_from_disk(const void *value, size_t size)
91 const char *end = (char *)value + size;
93 struct posix_acl *acl;
97 if (size < sizeof(reiserfs_acl_header))
98 return ERR_PTR(-EINVAL);
99 if (((reiserfs_acl_header *) value)->a_version !=
100 cpu_to_le32(REISERFS_ACL_VERSION))
101 return ERR_PTR(-EINVAL);
102 value = (char *)value + sizeof(reiserfs_acl_header);
103 count = reiserfs_acl_count(size);
105 return ERR_PTR(-EINVAL);
108 acl = posix_acl_alloc(count, GFP_NOFS);
110 return ERR_PTR(-ENOMEM);
111 for (n = 0; n < count; n++) {
112 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
113 if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
115 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
116 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
117 switch (acl->a_entries[n].e_tag) {
122 value = (char *)value +
123 sizeof(reiserfs_acl_entry_short);
124 acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
129 value = (char *)value + sizeof(reiserfs_acl_entry);
130 if ((char *)value > end)
132 acl->a_entries[n].e_id = le32_to_cpu(entry->e_id);
144 posix_acl_release(acl);
145 return ERR_PTR(-EINVAL);
149 * Convert from in-memory to filesystem representation.
151 static void *posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
153 reiserfs_acl_header *ext_acl;
157 *size = reiserfs_acl_size(acl->a_count);
158 ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
160 sizeof(reiserfs_acl_entry),
163 return ERR_PTR(-ENOMEM);
164 ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
165 e = (char *)ext_acl + sizeof(reiserfs_acl_header);
166 for (n = 0; n < acl->a_count; n++) {
167 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e;
168 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
169 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
170 switch (acl->a_entries[n].e_tag) {
173 entry->e_id = cpu_to_le32(acl->a_entries[n].e_id);
174 e += sizeof(reiserfs_acl_entry);
181 e += sizeof(reiserfs_acl_entry_short);
188 return (char *)ext_acl;
192 return ERR_PTR(-EINVAL);
196 * Inode operation get_posix_acl().
198 * inode->i_mutex: down
199 * BKL held [before 2.5.x]
201 struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
204 struct posix_acl *acl;
208 acl = get_cached_acl(inode, type);
209 if (acl != ACL_NOT_CACHED)
213 case ACL_TYPE_ACCESS:
214 name = POSIX_ACL_XATTR_ACCESS;
216 case ACL_TYPE_DEFAULT:
217 name = POSIX_ACL_XATTR_DEFAULT;
223 size = reiserfs_xattr_get(inode, name, NULL, 0);
225 if (size == -ENODATA || size == -ENOSYS) {
226 set_cached_acl(inode, type, NULL);
229 return ERR_PTR(size);
232 value = kmalloc(size, GFP_NOFS);
234 return ERR_PTR(-ENOMEM);
236 retval = reiserfs_xattr_get(inode, name, value, size);
237 if (retval == -ENODATA || retval == -ENOSYS) {
238 /* This shouldn't actually happen as it should have
239 been caught above.. but just in case */
241 } else if (retval < 0) {
242 acl = ERR_PTR(retval);
244 acl = posix_acl_from_disk(value, retval);
247 set_cached_acl(inode, type, acl);
254 * Inode operation set_posix_acl().
256 * inode->i_mutex: down
257 * BKL held [before 2.5.x]
260 reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
261 int type, struct posix_acl *acl)
268 if (S_ISLNK(inode->i_mode))
272 case ACL_TYPE_ACCESS:
273 name = POSIX_ACL_XATTR_ACCESS;
275 mode_t mode = inode->i_mode;
276 error = posix_acl_equiv_mode(acl, &mode);
280 inode->i_mode = mode;
286 case ACL_TYPE_DEFAULT:
287 name = POSIX_ACL_XATTR_DEFAULT;
288 if (!S_ISDIR(inode->i_mode))
289 return acl ? -EACCES : 0;
296 value = posix_acl_to_disk(acl, &size);
298 return (int)PTR_ERR(value);
301 error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
304 * Ensure that the inode gets dirtied if we're only using
305 * the mode bits and an old ACL didn't exist. We don't need
306 * to check if the inode is hashed here since we won't get
307 * called by reiserfs_inherit_default_acl().
309 if (error == -ENODATA) {
311 if (type == ACL_TYPE_ACCESS) {
312 inode->i_ctime = CURRENT_TIME_SEC;
313 mark_inode_dirty(inode);
320 set_cached_acl(inode, type, acl);
325 /* dir->i_mutex: locked,
326 * inode is new and not released into the wild yet */
328 reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
329 struct inode *dir, struct dentry *dentry,
332 struct posix_acl *acl;
335 /* ACLs only get applied to files and directories */
336 if (S_ISLNK(inode->i_mode))
339 /* ACLs can only be used on "new" objects, so if it's an old object
340 * there is nothing to inherit from */
341 if (get_inode_sd_version(dir) == STAT_DATA_V1)
344 /* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
345 * would be useless since permissions are ignored, and a pain because
346 * it introduces locking cycles */
347 if (IS_PRIVATE(dir)) {
348 inode->i_flags |= S_PRIVATE;
352 acl = reiserfs_get_acl(dir, ACL_TYPE_DEFAULT);
357 mode_t mode = inode->i_mode;
359 /* Copy the default ACL to the default ACL of a new directory */
360 if (S_ISDIR(inode->i_mode)) {
361 err = reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
367 /* Now we reconcile the new ACL and the mode,
368 potentially modifying both */
369 err = posix_acl_create(&acl, GFP_NOFS, &mode);
373 inode->i_mode = mode;
375 /* If we need an ACL.. */
377 err = reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS, acl);
379 posix_acl_release(acl);
382 /* no ACL, apply umask */
383 inode->i_mode &= ~current_umask();
389 /* This is used to cache the default acl before a new object is created.
390 * The biggest reason for this is to get an idea of how many blocks will
391 * actually be required for the create operation if we must inherit an ACL.
392 * An ACL write can add up to 3 object creations and an additional file write
393 * so we'd prefer not to reserve that many blocks in the journal if we can.
394 * It also has the advantage of not loading the ACL with a transaction open,
395 * this may seem silly, but if the owner of the directory is doing the
396 * creation, the ACL may not be loaded since the permissions wouldn't require
398 * We return the number of blocks required for the transaction.
400 int reiserfs_cache_default_acl(struct inode *inode)
402 struct posix_acl *acl;
405 if (IS_PRIVATE(inode))
408 acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
410 if (acl && !IS_ERR(acl)) {
411 int size = reiserfs_acl_size(acl->a_count);
413 /* Other xattrs can be created during inode creation. We don't
414 * want to claim too many blocks, so we check to see if we
415 * we need to create the tree to the xattrs, and then we
416 * just want two files. */
417 nblocks = reiserfs_xattr_jcreate_nblocks(inode);
418 nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
420 REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
422 /* We need to account for writes + bitmaps for two files */
423 nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
424 posix_acl_release(acl);
430 int reiserfs_acl_chmod(struct inode *inode)
432 struct reiserfs_transaction_handle th;
433 struct posix_acl *acl;
438 if (S_ISLNK(inode->i_mode))
441 if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
442 !reiserfs_posixacl(inode->i_sb)) {
446 reiserfs_write_unlock(inode->i_sb);
447 acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
448 reiserfs_write_lock(inode->i_sb);
453 error = posix_acl_chmod(&acl, GFP_NOFS, inode->i_mode);
457 size = reiserfs_xattr_nblocks(inode, reiserfs_acl_size(acl->a_count));
458 depth = reiserfs_write_lock_once(inode->i_sb);
459 error = journal_begin(&th, inode->i_sb, size * 2);
462 error = reiserfs_set_acl(&th, inode, ACL_TYPE_ACCESS, acl);
463 error2 = journal_end(&th, inode->i_sb, size * 2);
467 reiserfs_write_unlock_once(inode->i_sb, depth);
468 posix_acl_release(acl);
472 static size_t posix_acl_access_list(struct dentry *dentry, char *list,
473 size_t list_size, const char *name,
474 size_t name_len, int type)
476 const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
477 if (!reiserfs_posixacl(dentry->d_sb))
479 if (list && size <= list_size)
480 memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
484 const struct xattr_handler reiserfs_posix_acl_access_handler = {
485 .prefix = POSIX_ACL_XATTR_ACCESS,
486 .flags = ACL_TYPE_ACCESS,
487 .get = posix_acl_get,
488 .set = posix_acl_set,
489 .list = posix_acl_access_list,
492 static size_t posix_acl_default_list(struct dentry *dentry, char *list,
493 size_t list_size, const char *name,
494 size_t name_len, int type)
496 const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
497 if (!reiserfs_posixacl(dentry->d_sb))
499 if (list && size <= list_size)
500 memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
504 const struct xattr_handler reiserfs_posix_acl_default_handler = {
505 .prefix = POSIX_ACL_XATTR_DEFAULT,
506 .flags = ACL_TYPE_DEFAULT,
507 .get = posix_acl_get,
508 .set = posix_acl_set,
509 .list = posix_acl_default_list,