1 #include <linux/capability.h>
3 #include <linux/posix_acl.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>
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);
20 reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
23 struct reiserfs_transaction_handle th;
24 size_t jcreate_blocks;
25 int size = acl ? posix_acl_xattr_size(acl->a_count) : 0;
28 /* Pessimism: We can't assume that anything from the xattr root up
29 * has been created. */
31 jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
32 reiserfs_xattr_nblocks(inode, size) * 2;
34 reiserfs_write_lock(inode->i_sb);
35 error = journal_begin(&th, inode->i_sb, jcreate_blocks);
36 reiserfs_write_unlock(inode->i_sb);
38 error = __reiserfs_set_acl(&th, inode, type, acl);
39 reiserfs_write_lock(inode->i_sb);
40 error2 = journal_end(&th, inode->i_sb, jcreate_blocks);
41 reiserfs_write_unlock(inode->i_sb);
50 * Convert from filesystem to in-memory representation.
52 static struct posix_acl *reiserfs_posix_acl_from_disk(const void *value, size_t size)
54 const char *end = (char *)value + size;
56 struct posix_acl *acl;
60 if (size < sizeof(reiserfs_acl_header))
61 return ERR_PTR(-EINVAL);
62 if (((reiserfs_acl_header *) value)->a_version !=
63 cpu_to_le32(REISERFS_ACL_VERSION))
64 return ERR_PTR(-EINVAL);
65 value = (char *)value + sizeof(reiserfs_acl_header);
66 count = reiserfs_acl_count(size);
68 return ERR_PTR(-EINVAL);
71 acl = posix_acl_alloc(count, GFP_NOFS);
73 return ERR_PTR(-ENOMEM);
74 for (n = 0; n < count; n++) {
75 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
76 if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
78 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
79 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
80 switch (acl->a_entries[n].e_tag) {
85 value = (char *)value +
86 sizeof(reiserfs_acl_entry_short);
90 value = (char *)value + sizeof(reiserfs_acl_entry);
91 if ((char *)value > end)
93 acl->a_entries[n].e_uid =
94 make_kuid(&init_user_ns,
95 le32_to_cpu(entry->e_id));
98 value = (char *)value + sizeof(reiserfs_acl_entry);
99 if ((char *)value > end)
101 acl->a_entries[n].e_gid =
102 make_kgid(&init_user_ns,
103 le32_to_cpu(entry->e_id));
115 posix_acl_release(acl);
116 return ERR_PTR(-EINVAL);
120 * Convert from in-memory to filesystem representation.
122 static void *reiserfs_posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
124 reiserfs_acl_header *ext_acl;
128 *size = reiserfs_acl_size(acl->a_count);
129 ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
131 sizeof(reiserfs_acl_entry),
134 return ERR_PTR(-ENOMEM);
135 ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
136 e = (char *)ext_acl + sizeof(reiserfs_acl_header);
137 for (n = 0; n < acl->a_count; n++) {
138 const struct posix_acl_entry *acl_e = &acl->a_entries[n];
139 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e;
140 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
141 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
142 switch (acl->a_entries[n].e_tag) {
144 entry->e_id = cpu_to_le32(
145 from_kuid(&init_user_ns, acl_e->e_uid));
146 e += sizeof(reiserfs_acl_entry);
149 entry->e_id = cpu_to_le32(
150 from_kgid(&init_user_ns, acl_e->e_gid));
151 e += sizeof(reiserfs_acl_entry);
158 e += sizeof(reiserfs_acl_entry_short);
165 return (char *)ext_acl;
169 return ERR_PTR(-EINVAL);
173 * Inode operation get_posix_acl().
175 * inode->i_mutex: down
176 * BKL held [before 2.5.x]
178 struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
181 struct posix_acl *acl;
186 case ACL_TYPE_ACCESS:
187 name = POSIX_ACL_XATTR_ACCESS;
189 case ACL_TYPE_DEFAULT:
190 name = POSIX_ACL_XATTR_DEFAULT;
196 size = reiserfs_xattr_get(inode, name, NULL, 0);
198 if (size == -ENODATA || size == -ENOSYS) {
199 set_cached_acl(inode, type, NULL);
202 return ERR_PTR(size);
205 value = kmalloc(size, GFP_NOFS);
207 return ERR_PTR(-ENOMEM);
209 retval = reiserfs_xattr_get(inode, name, value, size);
210 if (retval == -ENODATA || retval == -ENOSYS) {
211 /* This shouldn't actually happen as it should have
212 been caught above.. but just in case */
214 } else if (retval < 0) {
215 acl = ERR_PTR(retval);
217 acl = reiserfs_posix_acl_from_disk(value, retval);
220 set_cached_acl(inode, type, acl);
227 * Inode operation set_posix_acl().
229 * inode->i_mutex: down
230 * BKL held [before 2.5.x]
233 __reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
234 int type, struct posix_acl *acl)
242 case ACL_TYPE_ACCESS:
243 name = POSIX_ACL_XATTR_ACCESS;
245 error = posix_acl_equiv_mode(acl, &inode->i_mode);
254 case ACL_TYPE_DEFAULT:
255 name = POSIX_ACL_XATTR_DEFAULT;
256 if (!S_ISDIR(inode->i_mode))
257 return acl ? -EACCES : 0;
264 value = reiserfs_posix_acl_to_disk(acl, &size);
266 return (int)PTR_ERR(value);
269 error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
272 * Ensure that the inode gets dirtied if we're only using
273 * the mode bits and an old ACL didn't exist. We don't need
274 * to check if the inode is hashed here since we won't get
275 * called by reiserfs_inherit_default_acl().
277 if (error == -ENODATA) {
279 if (type == ACL_TYPE_ACCESS) {
280 inode->i_ctime = CURRENT_TIME_SEC;
281 mark_inode_dirty(inode);
288 set_cached_acl(inode, type, acl);
293 /* dir->i_mutex: locked,
294 * inode is new and not released into the wild yet */
296 reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
297 struct inode *dir, struct dentry *dentry,
300 struct posix_acl *default_acl, *acl;
303 /* ACLs only get applied to files and directories */
304 if (S_ISLNK(inode->i_mode))
307 /* ACLs can only be used on "new" objects, so if it's an old object
308 * there is nothing to inherit from */
309 if (get_inode_sd_version(dir) == STAT_DATA_V1)
312 /* Don't apply ACLs to objects in the .reiserfs_priv tree.. This
313 * would be useless since permissions are ignored, and a pain because
314 * it introduces locking cycles */
315 if (IS_PRIVATE(dir)) {
316 inode->i_flags |= S_PRIVATE;
320 err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
325 err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
327 posix_acl_release(default_acl);
331 err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS,
333 posix_acl_release(acl);
339 /* no ACL, apply umask */
340 inode->i_mode &= ~current_umask();
344 /* This is used to cache the default acl before a new object is created.
345 * The biggest reason for this is to get an idea of how many blocks will
346 * actually be required for the create operation if we must inherit an ACL.
347 * An ACL write can add up to 3 object creations and an additional file write
348 * so we'd prefer not to reserve that many blocks in the journal if we can.
349 * It also has the advantage of not loading the ACL with a transaction open,
350 * this may seem silly, but if the owner of the directory is doing the
351 * creation, the ACL may not be loaded since the permissions wouldn't require
353 * We return the number of blocks required for the transaction.
355 int reiserfs_cache_default_acl(struct inode *inode)
357 struct posix_acl *acl;
360 if (IS_PRIVATE(inode))
363 acl = reiserfs_get_acl(inode, ACL_TYPE_DEFAULT);
365 if (acl && !IS_ERR(acl)) {
366 int size = reiserfs_acl_size(acl->a_count);
368 /* Other xattrs can be created during inode creation. We don't
369 * want to claim too many blocks, so we check to see if we
370 * we need to create the tree to the xattrs, and then we
371 * just want two files. */
372 nblocks = reiserfs_xattr_jcreate_nblocks(inode);
373 nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
375 REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
377 /* We need to account for writes + bitmaps for two files */
378 nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
379 posix_acl_release(acl);
386 * Called under i_mutex
388 int reiserfs_acl_chmod(struct inode *inode)
390 if (IS_PRIVATE(inode))
392 if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
393 !reiserfs_posixacl(inode->i_sb))
396 return posix_acl_chmod(inode, inode->i_mode);