* these are special cases for filesystem ACLs, they are interpreted by the
* kernel, in addition, they are negatively and positively cached and attached
* to the inode so that unnecessary lookups are avoided.
+ *
+ * Locking works like so:
+ * Directory components (xattr root, xattr dir) are protectd by their i_mutex.
+ * The xattrs themselves are protected by the xattr_sem.
*/
#include <linux/reiserfs_fs.h>
+#include <linux/capability.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include <linux/errno.h>
+#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/reiserfs_acl.h>
-#include <linux/mbcache.h>
#include <asm/uaccess.h>
-#include <asm/checksum.h>
-#include <linux/smp_lock.h>
+#include <net/checksum.h>
#include <linux/stat.h>
-#include <asm/semaphore.h>
+#include <linux/quotaops.h>
+#include <linux/security.h>
-#define FL_READONLY 128
-#define FL_DIR_SEM_HELD 256
#define PRIVROOT_NAME ".reiserfs_priv"
#define XAROOT_NAME "xattrs"
-static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char
- *prefix);
-static struct dentry *create_xa_root(struct super_block *sb)
+/* Helpers for inode ops. We do this so that we don't have all the VFS
+ * overhead and also for proper i_mutex annotation.
+ * dir->i_mutex must be held for all of them. */
+#ifdef CONFIG_REISERFS_FS_XATTR
+static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
{
- struct dentry *privroot = dget(REISERFS_SB(sb)->priv_root);
- struct dentry *xaroot;
-
- /* This needs to be created at mount-time */
- if (!privroot)
- return ERR_PTR(-EOPNOTSUPP);
-
- xaroot = lookup_one_len(XAROOT_NAME, privroot, strlen(XAROOT_NAME));
- if (IS_ERR(xaroot)) {
- goto out;
- } else if (!xaroot->d_inode) {
- int err;
- down(&privroot->d_inode->i_sem);
- err =
- privroot->d_inode->i_op->mkdir(privroot->d_inode, xaroot,
- 0700);
- up(&privroot->d_inode->i_sem);
-
- if (err) {
- dput(xaroot);
- dput(privroot);
- return ERR_PTR(err);
- }
- REISERFS_SB(sb)->xattr_root = dget(xaroot);
- }
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
+ return dir->i_op->create(dir, dentry, mode, NULL);
+}
+#endif
- out:
- dput(privroot);
- return xaroot;
+static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
+ return dir->i_op->mkdir(dir, dentry, mode);
}
-/* This will return a dentry, or error, refering to the xa root directory.
- * If the xa root doesn't exist yet, the dentry will be returned without
- * an associated inode. This dentry can be used with ->mkdir to create
- * the xa directory. */
-static struct dentry *__get_xa_root(struct super_block *s)
+/* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
+ * mutation ops aren't called during rename or splace, which are the
+ * only other users of I_MUTEX_CHILD. It violates the ordering, but that's
+ * better than allocating another subclass just for this code. */
+static int xattr_unlink(struct inode *dir, struct dentry *dentry)
{
- struct dentry *privroot = dget(REISERFS_SB(s)->priv_root);
- struct dentry *xaroot = NULL;
+ int error;
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
- if (IS_ERR(privroot) || !privroot)
- return privroot;
+ reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
+ I_MUTEX_CHILD, dir->i_sb);
+ error = dir->i_op->unlink(dir, dentry);
+ mutex_unlock(&dentry->d_inode->i_mutex);
- xaroot = lookup_one_len(XAROOT_NAME, privroot, strlen(XAROOT_NAME));
- if (IS_ERR(xaroot)) {
- goto out;
- } else if (!xaroot->d_inode) {
- dput(xaroot);
- xaroot = NULL;
- goto out;
- }
+ if (!error)
+ d_delete(dentry);
+ return error;
+}
- REISERFS_SB(s)->xattr_root = dget(xaroot);
+static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ int error;
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
+
+ reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex,
+ I_MUTEX_CHILD, dir->i_sb);
+ dentry_unhash(dentry);
+ error = dir->i_op->rmdir(dir, dentry);
+ if (!error)
+ dentry->d_inode->i_flags |= S_DEAD;
+ mutex_unlock(&dentry->d_inode->i_mutex);
+ if (!error)
+ d_delete(dentry);
+ dput(dentry);
- out:
- dput(privroot);
- return xaroot;
+ return error;
}
-/* Returns the dentry (or NULL) referring to the root of the extended
- * attribute directory tree. If it has already been retreived, it is used.
- * Otherwise, we attempt to retreive it from disk. It may also return
- * a pointer-encoded error.
- */
-static inline struct dentry *get_xa_root(struct super_block *s)
+#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
+
+static struct dentry *open_xa_root(struct super_block *sb, int flags)
{
- struct dentry *dentry = dget(REISERFS_SB(s)->xattr_root);
+ struct dentry *privroot = REISERFS_SB(sb)->priv_root;
+ struct dentry *xaroot;
+ if (!privroot->d_inode)
+ return ERR_PTR(-ENODATA);
+
+ mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR);
- if (!dentry)
- dentry = __get_xa_root(s);
+ xaroot = dget(REISERFS_SB(sb)->xattr_root);
+ if (!xaroot)
+ xaroot = ERR_PTR(-ENODATA);
+ else if (!xaroot->d_inode) {
+ int err = -ENODATA;
+ if (xattr_may_create(flags))
+ err = xattr_mkdir(privroot->d_inode, xaroot, 0700);
+ if (err) {
+ dput(xaroot);
+ xaroot = ERR_PTR(err);
+ }
+ }
- return dentry;
+ mutex_unlock(&privroot->d_inode->i_mutex);
+ return xaroot;
}
-/* Opens the directory corresponding to the inode's extended attribute store.
- * If flags allow, the tree to the directory may be created. If creation is
- * prohibited, -ENODATA is returned. */
static struct dentry *open_xa_dir(const struct inode *inode, int flags)
{
struct dentry *xaroot, *xadir;
char namebuf[17];
- xaroot = get_xa_root(inode->i_sb);
- if (IS_ERR(xaroot)) {
+ xaroot = open_xa_root(inode->i_sb, flags);
+ if (IS_ERR(xaroot))
return xaroot;
- } else if (!xaroot) {
- if (flags == 0 || flags & XATTR_CREATE) {
- xaroot = create_xa_root(inode->i_sb);
- if (IS_ERR(xaroot))
- return xaroot;
- }
- if (!xaroot)
- return ERR_PTR(-ENODATA);
- }
-
- /* ok, we have xaroot open */
snprintf(namebuf, sizeof(namebuf), "%X.%X",
le32_to_cpu(INODE_PKEY(inode)->k_objectid),
inode->i_generation);
- xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
- if (IS_ERR(xadir)) {
- dput(xaroot);
- return xadir;
- }
- if (!xadir->d_inode) {
- int err;
- if (flags == 0 || flags & XATTR_CREATE) {
- /* Although there is nothing else trying to create this directory,
- * another directory with the same hash may be created, so we need
- * to protect against that */
- err =
- xaroot->d_inode->i_op->mkdir(xaroot->d_inode, xadir,
- 0700);
- if (err) {
- dput(xaroot);
- dput(xadir);
- return ERR_PTR(err);
- }
- }
- if (!xadir->d_inode) {
- dput(xaroot);
+ mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR);
+
+ xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
+ if (!IS_ERR(xadir) && !xadir->d_inode) {
+ int err = -ENODATA;
+ if (xattr_may_create(flags))
+ err = xattr_mkdir(xaroot->d_inode, xadir, 0700);
+ if (err) {
dput(xadir);
- return ERR_PTR(-ENODATA);
+ xadir = ERR_PTR(err);
}
}
+ mutex_unlock(&xaroot->d_inode->i_mutex);
dput(xaroot);
return xadir;
}
-/* Returns a dentry corresponding to a specific extended attribute file
- * for the inode. If flags allow, the file is created. Otherwise, a
- * valid or negative dentry, or an error is returned. */
-static struct dentry *get_xa_file_dentry(const struct inode *inode,
- const char *name, int flags)
-{
- struct dentry *xadir, *xafile;
- int err = 0;
+/* The following are side effects of other operations that aren't explicitly
+ * modifying extended attributes. This includes operations such as permissions
+ * or ownership changes, object deletions, etc. */
+struct reiserfs_dentry_buf {
+ struct dentry *xadir;
+ int count;
+ struct dentry *dentries[8];
+};
- xadir = open_xa_dir(inode, flags);
- if (IS_ERR(xadir)) {
- return ERR_PTR(PTR_ERR(xadir));
- } else if (xadir && !xadir->d_inode) {
- dput(xadir);
- return ERR_PTR(-ENODATA);
- }
+static int
+fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset,
+ u64 ino, unsigned int d_type)
+{
+ struct reiserfs_dentry_buf *dbuf = buf;
+ struct dentry *dentry;
+ WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex));
- xafile = lookup_one_len(name, xadir, strlen(name));
- if (IS_ERR(xafile)) {
- dput(xadir);
- return ERR_PTR(PTR_ERR(xafile));
- }
+ if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
+ return -ENOSPC;
- if (xafile->d_inode) { /* file exists */
- if (flags & XATTR_CREATE) {
- err = -EEXIST;
- dput(xafile);
- goto out;
- }
- } else if (flags & XATTR_REPLACE || flags & FL_READONLY) {
- goto out;
- } else {
- /* inode->i_sem is down, so nothing else can try to create
- * the same xattr */
- err = xadir->d_inode->i_op->create(xadir->d_inode, xafile,
- 0700 | S_IFREG, NULL);
+ if (name[0] == '.' && (name[1] == '\0' ||
+ (name[1] == '.' && name[2] == '\0')))
+ return 0;
- if (err) {
- dput(xafile);
- goto out;
- }
+ dentry = lookup_one_len(name, dbuf->xadir, namelen);
+ if (IS_ERR(dentry)) {
+ return PTR_ERR(dentry);
+ } else if (!dentry->d_inode) {
+ /* A directory entry exists, but no file? */
+ reiserfs_error(dentry->d_sb, "xattr-20003",
+ "Corrupted directory: xattr %s listed but "
+ "not found for file %s.\n",
+ dentry->d_name.name, dbuf->xadir->d_name.name);
+ dput(dentry);
+ return -EIO;
}
- out:
- dput(xadir);
- if (err)
- xafile = ERR_PTR(err);
- return xafile;
+ dbuf->dentries[dbuf->count++] = dentry;
+ return 0;
}
-/* Opens a file pointer to the attribute associated with inode */
-static struct file *open_xa_file(const struct inode *inode, const char *name,
- int flags)
+static void
+cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
{
- struct dentry *xafile;
- struct file *fp;
-
- xafile = get_xa_file_dentry(inode, name, flags);
- if (IS_ERR(xafile))
- return ERR_PTR(PTR_ERR(xafile));
- else if (!xafile->d_inode) {
- dput(xafile);
- return ERR_PTR(-ENODATA);
- }
-
- fp = dentry_open(xafile, NULL, O_RDWR);
- /* dentry_open dputs the dentry if it fails */
-
- return fp;
+ int i;
+ for (i = 0; i < buf->count; i++)
+ if (buf->dentries[i])
+ dput(buf->dentries[i]);
}
-/*
- * this is very similar to fs/reiserfs/dir.c:reiserfs_readdir, but
- * we need to drop the path before calling the filldir struct. That
- * would be a big performance hit to the non-xattr case, so I've copied
- * the whole thing for now. --clm
- *
- * the big difference is that I go backwards through the directory,
- * and don't mess with f->f_pos, but the idea is the same. Do some
- * action on each and every entry in the directory.
- *
- * we're called with i_sem held, so there are no worries about the directory
- * changing underneath us.
- */
-static int __xattr_readdir(struct file *filp, void *dirent, filldir_t filldir)
+static int reiserfs_for_each_xattr(struct inode *inode,
+ int (*action)(struct dentry *, void *),
+ void *data)
{
- struct inode *inode = filp->f_dentry->d_inode;
- struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
- INITIALIZE_PATH(path_to_entry);
- struct buffer_head *bh;
- int entry_num;
- struct item_head *ih, tmp_ih;
- int search_res;
- char *local_buf;
- loff_t next_pos;
- char small_buf[32]; /* avoid kmalloc if we can */
- struct reiserfs_de_head *deh;
- int d_reclen;
- char *d_name;
- off_t d_off;
- ino_t d_ino;
- struct reiserfs_dir_entry de;
-
- /* form key for search the next directory entry using f_pos field of
- file structure */
- next_pos = max_reiserfs_offset(inode);
-
- while (1) {
- research:
- if (next_pos <= DOT_DOT_OFFSET)
- break;
- make_cpu_key(&pos_key, inode, next_pos, TYPE_DIRENTRY, 3);
-
- search_res =
- search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
- &de);
- if (search_res == IO_ERROR) {
- // FIXME: we could just skip part of directory which could
- // not be read
- pathrelse(&path_to_entry);
- return -EIO;
- }
-
- if (search_res == NAME_NOT_FOUND)
- de.de_entry_num--;
+ struct dentry *dir;
+ int i, err = 0;
+ loff_t pos = 0;
+ struct reiserfs_dentry_buf buf = {
+ .count = 0,
+ };
- set_de_name_and_namelen(&de);
- entry_num = de.de_entry_num;
- deh = &(de.de_deh[entry_num]);
+ /* Skip out, an xattr has no xattrs associated with it */
+ if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
+ return 0;
- bh = de.de_bh;
- ih = de.de_ih;
+ reiserfs_write_unlock(inode->i_sb);
+ dir = open_xa_dir(inode, XATTR_REPLACE);
+ if (IS_ERR(dir)) {
+ err = PTR_ERR(dir);
+ reiserfs_write_lock(inode->i_sb);
+ goto out;
+ } else if (!dir->d_inode) {
+ err = 0;
+ reiserfs_write_lock(inode->i_sb);
+ goto out_dir;
+ }
- if (!is_direntry_le_ih(ih)) {
- reiserfs_warning(inode->i_sb, "not direntry %h", ih);
- break;
- }
- copy_item_head(&tmp_ih, ih);
+ mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
- /* we must have found item, that is item of this directory, */
- RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
- "vs-9000: found item %h does not match to dir we readdir %K",
- ih, &pos_key);
+ reiserfs_write_lock(inode->i_sb);
- if (deh_offset(deh) <= DOT_DOT_OFFSET) {
- break;
- }
+ buf.xadir = dir;
+ err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
+ while ((err == 0 || err == -ENOSPC) && buf.count) {
+ err = 0;
- /* look for the previous entry in the directory */
- next_pos = deh_offset(deh) - 1;
+ for (i = 0; i < buf.count && buf.dentries[i]; i++) {
+ int lerr = 0;
+ struct dentry *dentry = buf.dentries[i];
- if (!de_visible(deh))
- /* it is hidden entry */
- continue;
+ if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
+ lerr = action(dentry, data);
- d_reclen = entry_length(bh, ih, entry_num);
- d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
- d_off = deh_offset(deh);
- d_ino = deh_objectid(deh);
+ dput(dentry);
+ buf.dentries[i] = NULL;
+ err = lerr ?: err;
+ }
+ buf.count = 0;
+ if (!err)
+ err = reiserfs_readdir_dentry(dir, &buf,
+ fill_with_dentries, &pos);
+ }
+ mutex_unlock(&dir->d_inode->i_mutex);
- if (!d_name[d_reclen - 1])
- d_reclen = strlen(d_name);
+ /* Clean up after a failed readdir */
+ cleanup_dentry_buf(&buf);
- if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)) {
- /* too big to send back to VFS */
- continue;
+ if (!err) {
+ /* We start a transaction here to avoid a ABBA situation
+ * between the xattr root's i_mutex and the journal lock.
+ * This doesn't incur much additional overhead since the
+ * new transaction will just nest inside the
+ * outer transaction. */
+ int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
+ 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
+ struct reiserfs_transaction_handle th;
+ err = journal_begin(&th, inode->i_sb, blocks);
+ if (!err) {
+ int jerror;
+ reiserfs_mutex_lock_nested_safe(
+ &dir->d_parent->d_inode->i_mutex,
+ I_MUTEX_XATTR, inode->i_sb);
+ err = action(dir, data);
+ jerror = journal_end(&th, inode->i_sb, blocks);
+ mutex_unlock(&dir->d_parent->d_inode->i_mutex);
+ err = jerror ?: err;
}
+ }
+out_dir:
+ dput(dir);
+out:
+ /* -ENODATA isn't an error */
+ if (err == -ENODATA)
+ err = 0;
+ return err;
+}
- /* Ignore the .reiserfs_priv entry */
- if (reiserfs_xattrs(inode->i_sb) &&
- !old_format_only(inode->i_sb) &&
- deh_objectid(deh) ==
- le32_to_cpu(INODE_PKEY
- (REISERFS_SB(inode->i_sb)->priv_root->d_inode)->
- k_objectid))
- continue;
-
- if (d_reclen <= 32) {
- local_buf = small_buf;
- } else {
- local_buf =
- reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb);
- if (!local_buf) {
- pathrelse(&path_to_entry);
- return -ENOMEM;
- }
- if (item_moved(&tmp_ih, &path_to_entry)) {
- reiserfs_kfree(local_buf, d_reclen,
- inode->i_sb);
+static int delete_one_xattr(struct dentry *dentry, void *data)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
- /* sigh, must retry. Do this same offset again */
- next_pos = d_off;
- goto research;
- }
- }
+ /* This is the xattr dir, handle specially. */
+ if (S_ISDIR(dentry->d_inode->i_mode))
+ return xattr_rmdir(dir, dentry);
- // Note, that we copy name to user space via temporary
- // buffer (local_buf) because filldir will block if
- // user space buffer is swapped out. At that time
- // entry can move to somewhere else
- memcpy(local_buf, d_name, d_reclen);
-
- /* the filldir function might need to start transactions,
- * or do who knows what. Release the path now that we've
- * copied all the important stuff out of the deh
- */
- pathrelse(&path_to_entry);
-
- if (filldir(dirent, local_buf, d_reclen, d_off, d_ino,
- DT_UNKNOWN) < 0) {
- if (local_buf != small_buf) {
- reiserfs_kfree(local_buf, d_reclen,
- inode->i_sb);
- }
- goto end;
- }
- if (local_buf != small_buf) {
- reiserfs_kfree(local_buf, d_reclen, inode->i_sb);
- }
- } /* while */
+ return xattr_unlink(dir, dentry);
+}
- end:
- pathrelse(&path_to_entry);
- return 0;
+static int chown_one_xattr(struct dentry *dentry, void *data)
+{
+ struct iattr *attrs = data;
+ return reiserfs_setattr(dentry, attrs);
}
-/*
- * this could be done with dedicated readdir ops for the xattr files,
- * but I want to get something working asap
- * this is stolen from vfs_readdir
- *
- */
-static
-int xattr_readdir(struct file *file, filldir_t filler, void *buf)
+/* No i_mutex, but the inode is unconnected. */
+int reiserfs_delete_xattrs(struct inode *inode)
{
- struct inode *inode = file->f_dentry->d_inode;
- int res = -ENOTDIR;
- if (!file->f_op || !file->f_op->readdir)
+ int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
+ if (err)
+ reiserfs_warning(inode->i_sb, "jdm-20004",
+ "Couldn't delete all xattrs (%d)\n", err);
+ return err;
+}
+
+/* inode->i_mutex: down */
+int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
+{
+ int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
+ if (err)
+ reiserfs_warning(inode->i_sb, "jdm-20007",
+ "Couldn't chown all xattrs (%d)\n", err);
+ return err;
+}
+
+#ifdef CONFIG_REISERFS_FS_XATTR
+/* Returns a dentry corresponding to a specific extended attribute file
+ * for the inode. If flags allow, the file is created. Otherwise, a
+ * valid or negative dentry, or an error is returned. */
+static struct dentry *xattr_lookup(struct inode *inode, const char *name,
+ int flags)
+{
+ struct dentry *xadir, *xafile;
+ int err = 0;
+
+ xadir = open_xa_dir(inode, flags);
+ if (IS_ERR(xadir))
+ return ERR_CAST(xadir);
+
+ mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
+ xafile = lookup_one_len(name, xadir, strlen(name));
+ if (IS_ERR(xafile)) {
+ err = PTR_ERR(xafile);
goto out;
- down(&inode->i_sem);
-// down(&inode->i_zombie);
- res = -ENOENT;
- if (!IS_DEADDIR(inode)) {
- lock_kernel();
- res = __xattr_readdir(file, buf, filler);
- unlock_kernel();
}
-// up(&inode->i_zombie);
- up(&inode->i_sem);
- out:
- return res;
+
+ if (xafile->d_inode && (flags & XATTR_CREATE))
+ err = -EEXIST;
+
+ if (!xafile->d_inode) {
+ err = -ENODATA;
+ if (xattr_may_create(flags))
+ err = xattr_create(xadir->d_inode, xafile,
+ 0700|S_IFREG);
+ }
+
+ if (err)
+ dput(xafile);
+out:
+ mutex_unlock(&xadir->d_inode->i_mutex);
+ dput(xadir);
+ if (err)
+ return ERR_PTR(err);
+ return xafile;
}
/* Internal operations on file data */
page_cache_release(page);
}
-static struct page *reiserfs_get_page(struct inode *dir, unsigned long n)
+static struct page *reiserfs_get_page(struct inode *dir, size_t n)
{
struct address_space *mapping = dir->i_mapping;
struct page *page;
/* We can deadlock if we try to free dentries,
and an unlink/rmdir has just occured - GFP_NOFS avoids this */
- mapping->flags = (mapping->flags & ~__GFP_BITS_MASK) | GFP_NOFS;
- page = read_cache_page(mapping, n,
- (filler_t *) mapping->a_ops->readpage, NULL);
+ mapping_set_gfp_mask(mapping, GFP_NOFS);
+ page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
if (!IS_ERR(page)) {
- wait_on_page_locked(page);
kmap(page);
- if (!PageUptodate(page))
- goto fail;
-
if (PageError(page))
goto fail;
}
return csum_partial(msg, len, 0);
}
+int reiserfs_commit_write(struct file *f, struct page *page,
+ unsigned from, unsigned to);
+int reiserfs_prepare_write(struct file *f, struct page *page,
+ unsigned from, unsigned to);
+
+static void update_ctime(struct inode *inode)
+{
+ struct timespec now = current_fs_time(inode->i_sb);
+ if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink ||
+ timespec_equal(&inode->i_ctime, &now))
+ return;
+
+ inode->i_ctime = CURRENT_TIME_SEC;
+ mark_inode_dirty(inode);
+}
+
+static int lookup_and_delete_xattr(struct inode *inode, const char *name)
+{
+ int err = 0;
+ struct dentry *dentry, *xadir;
+
+ xadir = open_xa_dir(inode, XATTR_REPLACE);
+ if (IS_ERR(xadir))
+ return PTR_ERR(xadir);
+
+ mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR);
+ dentry = lookup_one_len(name, xadir, strlen(name));
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out_dput;
+ }
+
+ if (dentry->d_inode) {
+ reiserfs_write_lock(inode->i_sb);
+ err = xattr_unlink(xadir->d_inode, dentry);
+ reiserfs_write_unlock(inode->i_sb);
+ update_ctime(inode);
+ }
+
+ dput(dentry);
+out_dput:
+ mutex_unlock(&xadir->d_inode->i_mutex);
+ dput(xadir);
+ return err;
+}
+
+
/* Generic extended attribute operations that can be used by xa plugins */
/*
- * inode->i_sem: down
+ * inode->i_mutex: down
*/
int
-reiserfs_xattr_set(struct inode *inode, const char *name, const void *buffer,
- size_t buffer_size, int flags)
+reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
+ struct inode *inode, const char *name,
+ const void *buffer, size_t buffer_size, int flags)
{
int err = 0;
- struct file *fp;
+ struct dentry *dentry;
struct page *page;
char *data;
- struct address_space *mapping;
size_t file_pos = 0;
size_t buffer_pos = 0;
- struct inode *xinode;
- struct iattr newattrs;
+ size_t new_size;
__u32 xahash = 0;
- if (IS_RDONLY(inode))
- return -EROFS;
-
- if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
- return -EPERM;
-
if (get_inode_sd_version(inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
- /* Empty xattrs are ok, they're just empty files, no hash */
- if (buffer && buffer_size)
- xahash = xattr_hash(buffer, buffer_size);
+ reiserfs_write_unlock(inode->i_sb);
- open_file:
- fp = open_xa_file(inode, name, flags);
- if (IS_ERR(fp)) {
- err = PTR_ERR(fp);
- goto out;
+ if (!buffer) {
+ err = lookup_and_delete_xattr(inode, name);
+ reiserfs_write_lock(inode->i_sb);
+ return err;
}
- xinode = fp->f_dentry->d_inode;
- REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
-
- /* we need to copy it off.. */
- if (xinode->i_nlink > 1) {
- fput(fp);
- err = reiserfs_xattr_del(inode, name);
- if (err < 0)
- goto out;
- /* We just killed the old one, we're not replacing anymore */
- if (flags & XATTR_REPLACE)
- flags &= ~XATTR_REPLACE;
- goto open_file;
+ dentry = xattr_lookup(inode, name, flags);
+ if (IS_ERR(dentry)) {
+ reiserfs_write_lock(inode->i_sb);
+ return PTR_ERR(dentry);
}
- /* Resize it so we're ok to write there */
- newattrs.ia_size = buffer_size;
- newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
- down(&xinode->i_sem);
- err = notify_change(fp->f_dentry, &newattrs);
- if (err)
- goto out_filp;
+ down_write(&REISERFS_I(inode)->i_xattr_sem);
- mapping = xinode->i_mapping;
+ reiserfs_write_lock(inode->i_sb);
+
+ xahash = xattr_hash(buffer, buffer_size);
while (buffer_pos < buffer_size || buffer_pos == 0) {
size_t chunk;
size_t skip = 0;
else
chunk = buffer_size - buffer_pos;
- page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT);
+ page = reiserfs_get_page(dentry->d_inode, file_pos);
if (IS_ERR(page)) {
err = PTR_ERR(page);
- goto out_filp;
+ goto out_unlock;
}
lock_page(page);
rxh->h_hash = cpu_to_le32(xahash);
}
- err = mapping->a_ops->prepare_write(fp, page, page_offset,
- page_offset + chunk + skip);
+ err = reiserfs_prepare_write(NULL, page, page_offset,
+ page_offset + chunk + skip);
if (!err) {
if (buffer)
memcpy(data + skip, buffer + buffer_pos, chunk);
- err =
- mapping->a_ops->commit_write(fp, page, page_offset,
- page_offset + chunk +
- skip);
+ err = reiserfs_commit_write(NULL, page, page_offset,
+ page_offset + chunk +
+ skip);
}
unlock_page(page);
reiserfs_put_page(page);
break;
}
- /* We can't mark the inode dirty if it's not hashed. This is the case
- * when we're inheriting the default ACL. If we dirty it, the inode
- * gets marked dirty, but won't (ever) make it onto the dirty list until
- * it's synced explicitly to clear I_DIRTY. This is bad. */
- if (!hlist_unhashed(&inode->i_hash)) {
- inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
+ new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
+ if (!err && new_size < i_size_read(dentry->d_inode)) {
+ struct iattr newattrs = {
+ .ia_ctime = current_fs_time(inode->i_sb),
+ .ia_size = new_size,
+ .ia_valid = ATTR_SIZE | ATTR_CTIME,
+ };
+
+ reiserfs_write_unlock(inode->i_sb);
+ mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
+ down_write(&dentry->d_inode->i_alloc_sem);
+ reiserfs_write_lock(inode->i_sb);
+
+ err = reiserfs_setattr(dentry, &newattrs);
+ up_write(&dentry->d_inode->i_alloc_sem);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+ } else
+ update_ctime(inode);
+out_unlock:
+ up_write(&REISERFS_I(inode)->i_xattr_sem);
+ dput(dentry);
+ return err;
+}
+
+/* We need to start a transaction to maintain lock ordering */
+int reiserfs_xattr_set(struct inode *inode, const char *name,
+ const void *buffer, size_t buffer_size, int flags)
+{
+
+ struct reiserfs_transaction_handle th;
+ int error, error2;
+ size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
+
+ if (!(flags & XATTR_REPLACE))
+ jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
+
+ reiserfs_write_lock(inode->i_sb);
+ error = journal_begin(&th, inode->i_sb, jbegin_count);
+ if (error) {
+ reiserfs_write_unlock(inode->i_sb);
+ return error;
}
- out_filp:
- up(&xinode->i_sem);
- fput(fp);
+ error = reiserfs_xattr_set_handle(&th, inode, name,
+ buffer, buffer_size, flags);
- out:
- return err;
+ error2 = journal_end(&th, inode->i_sb, jbegin_count);
+ if (error == 0)
+ error = error2;
+ reiserfs_write_unlock(inode->i_sb);
+
+ return error;
}
/*
- * inode->i_sem: down
+ * inode->i_mutex: down
*/
int
-reiserfs_xattr_get(const struct inode *inode, const char *name, void *buffer,
+reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
size_t buffer_size)
{
ssize_t err = 0;
- struct file *fp;
+ struct dentry *dentry;
size_t isize;
size_t file_pos = 0;
size_t buffer_pos = 0;
struct page *page;
- struct inode *xinode;
__u32 hash = 0;
if (name == NULL)
if (get_inode_sd_version(inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
- fp = open_xa_file(inode, name, FL_READONLY);
- if (IS_ERR(fp)) {
- err = PTR_ERR(fp);
+ dentry = xattr_lookup(inode, name, XATTR_REPLACE);
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
goto out;
}
- xinode = fp->f_dentry->d_inode;
- isize = xinode->i_size;
- REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
+ down_read(&REISERFS_I(inode)->i_xattr_sem);
+
+ isize = i_size_read(dentry->d_inode);
/* Just return the size needed */
if (buffer == NULL) {
err = isize - sizeof(struct reiserfs_xattr_header);
- goto out_dput;
+ goto out_unlock;
}
if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
err = -ERANGE;
- goto out_dput;
+ goto out_unlock;
}
while (file_pos < isize) {
else
chunk = isize - file_pos;
- page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT);
+ page = reiserfs_get_page(dentry->d_inode, file_pos);
if (IS_ERR(page)) {
err = PTR_ERR(page);
- goto out_dput;
+ goto out_unlock;
}
lock_page(page);
if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
unlock_page(page);
reiserfs_put_page(page);
- reiserfs_warning(inode->i_sb,
+ reiserfs_warning(inode->i_sb, "jdm-20001",
"Invalid magic for xattr (%s) "
"associated with %k", name,
INODE_PKEY(inode));
err = -EIO;
- goto out_dput;
+ goto out_unlock;
}
hash = le32_to_cpu(rxh->h_hash);
}
if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
hash) {
- reiserfs_warning(inode->i_sb,
+ reiserfs_warning(inode->i_sb, "jdm-20002",
"Invalid hash for xattr (%s) associated "
"with %k", name, INODE_PKEY(inode));
err = -EIO;
}
- out_dput:
- fput(fp);
-
- out:
- return err;
-}
-
-static int
-__reiserfs_xattr_del(struct dentry *xadir, const char *name, int namelen)
-{
- struct dentry *dentry;
- struct inode *dir = xadir->d_inode;
- int err = 0;
-
- dentry = lookup_one_len(name, xadir, namelen);
- if (IS_ERR(dentry)) {
- err = PTR_ERR(dentry);
- goto out;
- } else if (!dentry->d_inode) {
- err = -ENODATA;
- goto out_file;
- }
-
- /* Skip directories.. */
- if (S_ISDIR(dentry->d_inode->i_mode))
- goto out_file;
-
- if (!is_reiserfs_priv_object(dentry->d_inode)) {
- reiserfs_warning(dir->i_sb, "OID %08x [%.*s/%.*s] doesn't have "
- "priv flag set [parent is %sset].",
- le32_to_cpu(INODE_PKEY(dentry->d_inode)->
- k_objectid), xadir->d_name.len,
- xadir->d_name.name, namelen, name,
- is_reiserfs_priv_object(xadir->
- d_inode) ? "" :
- "not ");
- dput(dentry);
- return -EIO;
- }
-
- err = dir->i_op->unlink(dir, dentry);
- if (!err)
- d_delete(dentry);
-
- out_file:
+out_unlock:
+ up_read(&REISERFS_I(inode)->i_xattr_sem);
dput(dentry);
- out:
+out:
return err;
}
-int reiserfs_xattr_del(struct inode *inode, const char *name)
-{
- struct dentry *dir;
- int err;
-
- if (IS_RDONLY(inode))
- return -EROFS;
-
- dir = open_xa_dir(inode, FL_READONLY);
- if (IS_ERR(dir)) {
- err = PTR_ERR(dir);
- goto out;
- }
-
- err = __reiserfs_xattr_del(dir, name, strlen(name));
- dput(dir);
-
- if (!err) {
- inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(inode);
- }
-
- out:
- return err;
-}
-
-/* The following are side effects of other operations that aren't explicitly
- * modifying extended attributes. This includes operations such as permissions
- * or ownership changes, object deletions, etc. */
-
-static int
-reiserfs_delete_xattrs_filler(void *buf, const char *name, int namelen,
- loff_t offset, ino_t ino, unsigned int d_type)
-{
- struct dentry *xadir = (struct dentry *)buf;
-
- return __reiserfs_xattr_del(xadir, name, namelen);
-
-}
-
-/* This is called w/ inode->i_sem downed */
-int reiserfs_delete_xattrs(struct inode *inode)
-{
- struct file *fp;
- struct dentry *dir, *root;
- int err = 0;
-
- /* Skip out, an xattr has no xattrs associated with it */
- if (is_reiserfs_priv_object(inode) ||
- get_inode_sd_version(inode) == STAT_DATA_V1 ||
- !reiserfs_xattrs(inode->i_sb)) {
- return 0;
- }
- reiserfs_read_lock_xattrs(inode->i_sb);
- dir = open_xa_dir(inode, FL_READONLY);
- reiserfs_read_unlock_xattrs(inode->i_sb);
- if (IS_ERR(dir)) {
- err = PTR_ERR(dir);
- goto out;
- } else if (!dir->d_inode) {
- dput(dir);
- return 0;
- }
-
- fp = dentry_open(dir, NULL, O_RDWR);
- if (IS_ERR(fp)) {
- err = PTR_ERR(fp);
- /* dentry_open dputs the dentry if it fails */
- goto out;
- }
-
- lock_kernel();
- err = xattr_readdir(fp, reiserfs_delete_xattrs_filler, dir);
- if (err) {
- unlock_kernel();
- goto out_dir;
- }
-
- /* Leftovers besides . and .. -- that's not good. */
- if (dir->d_inode->i_nlink <= 2) {
- root = get_xa_root(inode->i_sb);
- reiserfs_write_lock_xattrs(inode->i_sb);
- err = vfs_rmdir(root->d_inode, dir);
- reiserfs_write_unlock_xattrs(inode->i_sb);
- dput(root);
- } else {
- reiserfs_warning(inode->i_sb,
- "Couldn't remove all entries in directory");
- }
- unlock_kernel();
-
- out_dir:
- fput(fp);
-
- out:
- if (!err)
- REISERFS_I(inode)->i_flags =
- REISERFS_I(inode)->i_flags & ~i_has_xattr_dir;
- return err;
-}
-
-struct reiserfs_chown_buf {
- struct inode *inode;
- struct dentry *xadir;
- struct iattr *attrs;
-};
-
-/* XXX: If there is a better way to do this, I'd love to hear about it */
-static int
-reiserfs_chown_xattrs_filler(void *buf, const char *name, int namelen,
- loff_t offset, ino_t ino, unsigned int d_type)
-{
- struct reiserfs_chown_buf *chown_buf = (struct reiserfs_chown_buf *)buf;
- struct dentry *xafile, *xadir = chown_buf->xadir;
- struct iattr *attrs = chown_buf->attrs;
- int err = 0;
-
- xafile = lookup_one_len(name, xadir, namelen);
- if (IS_ERR(xafile))
- return PTR_ERR(xafile);
- else if (!xafile->d_inode) {
- dput(xafile);
- return -ENODATA;
- }
-
- if (!S_ISDIR(xafile->d_inode->i_mode))
- err = notify_change(xafile, attrs);
- dput(xafile);
-
- return err;
-}
+/*
+ * In order to implement different sets of xattr operations for each xattr
+ * prefix with the generic xattr API, a filesystem should create a
+ * null-terminated array of struct xattr_handler (one for each prefix) and
+ * hang a pointer to it off of the s_xattr field of the superblock.
+ *
+ * The generic_fooxattr() functions will use this list to dispatch xattr
+ * operations to the correct xattr_handler.
+ */
+#define for_each_xattr_handler(handlers, handler) \
+ for ((handler) = *(handlers)++; \
+ (handler) != NULL; \
+ (handler) = *(handlers)++)
-int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
+/* This is the implementation for the xattr plugin infrastructure */
+static inline struct xattr_handler *
+find_xattr_handler_prefix(struct xattr_handler **handlers,
+ const char *name)
{
- struct file *fp;
- struct dentry *dir;
- int err = 0;
- struct reiserfs_chown_buf buf;
- unsigned int ia_valid = attrs->ia_valid;
-
- /* Skip out, an xattr has no xattrs associated with it */
- if (is_reiserfs_priv_object(inode) ||
- get_inode_sd_version(inode) == STAT_DATA_V1 ||
- !reiserfs_xattrs(inode->i_sb)) {
- return 0;
- }
- reiserfs_read_lock_xattrs(inode->i_sb);
- dir = open_xa_dir(inode, FL_READONLY);
- reiserfs_read_unlock_xattrs(inode->i_sb);
- if (IS_ERR(dir)) {
- if (PTR_ERR(dir) != -ENODATA)
- err = PTR_ERR(dir);
- goto out;
- } else if (!dir->d_inode) {
- dput(dir);
- goto out;
- }
-
- fp = dentry_open(dir, NULL, O_RDWR);
- if (IS_ERR(fp)) {
- err = PTR_ERR(fp);
- /* dentry_open dputs the dentry if it fails */
- goto out;
- }
-
- lock_kernel();
+ struct xattr_handler *xah;
- attrs->ia_valid &= (ATTR_UID | ATTR_GID | ATTR_CTIME);
- buf.xadir = dir;
- buf.attrs = attrs;
- buf.inode = inode;
+ if (!handlers)
+ return NULL;
- err = xattr_readdir(fp, reiserfs_chown_xattrs_filler, &buf);
- if (err) {
- unlock_kernel();
- goto out_dir;
+ for_each_xattr_handler(handlers, xah) {
+ if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
+ break;
}
- err = notify_change(dir, attrs);
- unlock_kernel();
-
- out_dir:
- fput(fp);
-
- out:
- attrs->ia_valid = ia_valid;
- return err;
+ return xah;
}
-/* Actual operations that are exported to VFS-land */
/*
* Inode operation getxattr()
- * Preliminary locking: we down dentry->d_inode->i_sem
*/
ssize_t
reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
size_t size)
{
- struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name);
- int err;
+ struct xattr_handler *handler;
- if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
- get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
+ handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
+
+ if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
- reiserfs_read_lock_xattr_i(dentry->d_inode);
- reiserfs_read_lock_xattrs(dentry->d_sb);
- err = xah->get(dentry->d_inode, name, buffer, size);
- reiserfs_read_unlock_xattrs(dentry->d_sb);
- reiserfs_read_unlock_xattr_i(dentry->d_inode);
- return err;
+ return handler->get(dentry, name, buffer, size, handler->flags);
}
/*
* Inode operation setxattr()
*
- * dentry->d_inode->i_sem down
+ * dentry->d_inode->i_mutex down
*/
int
reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
size_t size, int flags)
{
- struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name);
- int err;
- int lock;
+ struct xattr_handler *handler;
- if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
- get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
- return -EOPNOTSUPP;
-
- if (IS_RDONLY(dentry->d_inode))
- return -EROFS;
+ handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
- if (IS_IMMUTABLE(dentry->d_inode) || IS_APPEND(dentry->d_inode))
- return -EROFS;
+ if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
+ return -EOPNOTSUPP;
- reiserfs_write_lock_xattr_i(dentry->d_inode);
- lock = !has_xattr_dir(dentry->d_inode);
- if (lock)
- reiserfs_write_lock_xattrs(dentry->d_sb);
- else
- reiserfs_read_lock_xattrs(dentry->d_sb);
- err = xah->set(dentry->d_inode, name, value, size, flags);
- if (lock)
- reiserfs_write_unlock_xattrs(dentry->d_sb);
- else
- reiserfs_read_unlock_xattrs(dentry->d_sb);
- reiserfs_write_unlock_xattr_i(dentry->d_inode);
- return err;
+ return handler->set(dentry, name, value, size, flags, handler->flags);
}
/*
* Inode operation removexattr()
*
- * dentry->d_inode->i_sem down
+ * dentry->d_inode->i_mutex down
*/
int reiserfs_removexattr(struct dentry *dentry, const char *name)
{
- int err;
- struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name);
+ struct xattr_handler *handler;
+ handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
- if (!xah || !reiserfs_xattrs(dentry->d_sb) ||
- get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
+ if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
- if (IS_RDONLY(dentry->d_inode))
- return -EROFS;
-
- if (IS_IMMUTABLE(dentry->d_inode) || IS_APPEND(dentry->d_inode))
- return -EPERM;
-
- reiserfs_write_lock_xattr_i(dentry->d_inode);
- reiserfs_read_lock_xattrs(dentry->d_sb);
-
- /* Deletion pre-operation */
- if (xah->del) {
- err = xah->del(dentry->d_inode, name);
- if (err)
- goto out;
- }
-
- err = reiserfs_xattr_del(dentry->d_inode, name);
-
- dentry->d_inode->i_ctime = CURRENT_TIME_SEC;
- mark_inode_dirty(dentry->d_inode);
-
- out:
- reiserfs_read_unlock_xattrs(dentry->d_sb);
- reiserfs_write_unlock_xattr_i(dentry->d_inode);
- return err;
+ return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
}
-/* This is what filldir will use:
- * r_pos will always contain the amount of space required for the entire
- * list. If r_pos becomes larger than r_size, we need more space and we
- * return an error indicating this. If r_pos is less than r_size, then we've
- * filled the buffer successfully and we return success */
-struct reiserfs_listxattr_buf {
- int r_pos;
- int r_size;
- char *r_buf;
- struct inode *r_inode;
+struct listxattr_buf {
+ size_t size;
+ size_t pos;
+ char *buf;
+ struct dentry *dentry;
};
-static int
-reiserfs_listxattr_filler(void *buf, const char *name, int namelen,
- loff_t offset, ino_t ino, unsigned int d_type)
+static int listxattr_filler(void *buf, const char *name, int namelen,
+ loff_t offset, u64 ino, unsigned int d_type)
{
- struct reiserfs_listxattr_buf *b = (struct reiserfs_listxattr_buf *)buf;
- int len = 0;
- if (name[0] != '.'
- || (namelen != 1 && (name[1] != '.' || namelen != 2))) {
- struct reiserfs_xattr_handler *xah =
- find_xattr_handler_prefix(name);
- if (!xah)
- return 0; /* Unsupported xattr name, skip it */
-
- /* We call ->list() twice because the operation isn't required to just
- * return the name back - we want to make sure we have enough space */
- len += xah->list(b->r_inode, name, namelen, NULL);
-
- if (len) {
- if (b->r_pos + len + 1 <= b->r_size) {
- char *p = b->r_buf + b->r_pos;
- p += xah->list(b->r_inode, name, namelen, p);
- *p++ = '\0';
- }
- b->r_pos += len + 1;
+ struct listxattr_buf *b = (struct listxattr_buf *)buf;
+ size_t size;
+ if (name[0] != '.' ||
+ (namelen != 1 && (name[1] != '.' || namelen != 2))) {
+ struct xattr_handler *handler;
+ handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
+ name);
+ if (!handler) /* Unsupported xattr name */
+ return 0;
+ if (b->buf) {
+ size = handler->list(b->dentry, b->buf + b->pos,
+ b->size, name, namelen,
+ handler->flags);
+ if (size > b->size)
+ return -ERANGE;
+ } else {
+ size = handler->list(b->dentry, NULL, 0, name,
+ namelen, handler->flags);
}
- }
+ b->pos += size;
+ }
return 0;
}
/*
* Inode operation listxattr()
*
- * Preliminary locking: we down dentry->d_inode->i_sem
+ * We totally ignore the generic listxattr here because it would be stupid
+ * not to. Since the xattrs are organized in a directory, we can just
+ * readdir to find them.
*/
ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
{
- struct file *fp;
struct dentry *dir;
int err = 0;
- struct reiserfs_listxattr_buf buf;
+ loff_t pos = 0;
+ struct listxattr_buf buf = {
+ .dentry = dentry,
+ .buf = buffer,
+ .size = buffer ? size : 0,
+ };
if (!dentry->d_inode)
return -EINVAL;
- if (!reiserfs_xattrs(dentry->d_sb) ||
+ if (!dentry->d_sb->s_xattr ||
get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
- reiserfs_read_lock_xattr_i(dentry->d_inode);
- reiserfs_read_lock_xattrs(dentry->d_sb);
- dir = open_xa_dir(dentry->d_inode, FL_READONLY);
- reiserfs_read_unlock_xattrs(dentry->d_sb);
+ dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE);
if (IS_ERR(dir)) {
err = PTR_ERR(dir);
if (err == -ENODATA)
- err = 0; /* Not an error if there aren't any xattrs */
- goto out;
- }
-
- fp = dentry_open(dir, NULL, O_RDWR);
- if (IS_ERR(fp)) {
- err = PTR_ERR(fp);
- /* dentry_open dputs the dentry if it fails */
+ err = 0; /* Not an error if there aren't any xattrs */
goto out;
}
- buf.r_buf = buffer;
- buf.r_size = buffer ? size : 0;
- buf.r_pos = 0;
- buf.r_inode = dentry->d_inode;
+ mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
+ err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos);
+ mutex_unlock(&dir->d_inode->i_mutex);
- REISERFS_I(dentry->d_inode)->i_flags |= i_has_xattr_dir;
-
- err = xattr_readdir(fp, reiserfs_listxattr_filler, &buf);
- if (err)
- goto out_dir;
-
- if (buf.r_pos > buf.r_size && buffer != NULL)
- err = -ERANGE;
- else
- err = buf.r_pos;
-
- out_dir:
- fput(fp);
+ if (!err)
+ err = buf.pos;
- out:
- reiserfs_read_unlock_xattr_i(dentry->d_inode);
+ dput(dir);
+out:
return err;
}
-/* This is the implementation for the xattr plugin infrastructure */
-static struct list_head xattr_handlers = LIST_HEAD_INIT(xattr_handlers);
-static DEFINE_RWLOCK(handler_lock);
-
-static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char
- *prefix)
+static int reiserfs_check_acl(struct inode *inode, int mask)
{
- struct reiserfs_xattr_handler *xah = NULL;
- struct list_head *p;
+ struct posix_acl *acl;
+ int error = -EAGAIN; /* do regular unix permission checks by default */
- read_lock(&handler_lock);
- list_for_each(p, &xattr_handlers) {
- xah = list_entry(p, struct reiserfs_xattr_handler, handlers);
- if (strncmp(xah->prefix, prefix, strlen(xah->prefix)) == 0)
- break;
- xah = NULL;
+ acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
+
+ if (acl) {
+ if (!IS_ERR(acl)) {
+ error = posix_acl_permission(inode, acl, mask);
+ posix_acl_release(acl);
+ } else if (PTR_ERR(acl) != -ENODATA)
+ error = PTR_ERR(acl);
}
- read_unlock(&handler_lock);
- return xah;
+ return error;
}
-static void __unregister_handlers(void)
+static int create_privroot(struct dentry *dentry)
{
- struct reiserfs_xattr_handler *xah;
- struct list_head *p, *tmp;
-
- list_for_each_safe(p, tmp, &xattr_handlers) {
- xah = list_entry(p, struct reiserfs_xattr_handler, handlers);
- if (xah->exit)
- xah->exit();
-
- list_del_init(p);
+ int err;
+ struct inode *inode = dentry->d_parent->d_inode;
+ WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
+
+ err = xattr_mkdir(inode, dentry, 0700);
+ if (err || !dentry->d_inode) {
+ reiserfs_warning(dentry->d_sb, "jdm-20006",
+ "xattrs/ACLs enabled and couldn't "
+ "find/create .reiserfs_priv. "
+ "Failing mount.");
+ return -EOPNOTSUPP;
}
- INIT_LIST_HEAD(&xattr_handlers);
-}
-int __init reiserfs_xattr_register_handlers(void)
-{
- int err = 0;
- struct reiserfs_xattr_handler *xah;
- struct list_head *p;
+ dentry->d_inode->i_flags |= S_PRIVATE;
+ reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
+ "storage.\n", PRIVROOT_NAME);
- write_lock(&handler_lock);
+ return 0;
+}
- /* If we're already initialized, nothing to do */
- if (!list_empty(&xattr_handlers)) {
- write_unlock(&handler_lock);
- return 0;
- }
+#else
+int __init reiserfs_xattr_register_handlers(void) { return 0; }
+void reiserfs_xattr_unregister_handlers(void) {}
+static int create_privroot(struct dentry *dentry) { return 0; }
+#endif
- /* Add the handlers */
- list_add_tail(&user_handler.handlers, &xattr_handlers);
- list_add_tail(&trusted_handler.handlers, &xattr_handlers);
+/* Actual operations that are exported to VFS-land */
+struct xattr_handler *reiserfs_xattr_handlers[] = {
+#ifdef CONFIG_REISERFS_FS_XATTR
+ &reiserfs_xattr_user_handler,
+ &reiserfs_xattr_trusted_handler,
+#endif
#ifdef CONFIG_REISERFS_FS_SECURITY
- list_add_tail(&security_handler.handlers, &xattr_handlers);
+ &reiserfs_xattr_security_handler,
#endif
#ifdef CONFIG_REISERFS_FS_POSIX_ACL
- list_add_tail(&posix_acl_access_handler.handlers, &xattr_handlers);
- list_add_tail(&posix_acl_default_handler.handlers, &xattr_handlers);
+ &reiserfs_posix_acl_access_handler,
+ &reiserfs_posix_acl_default_handler,
#endif
+ NULL
+};
- /* Run initializers, if available */
- list_for_each(p, &xattr_handlers) {
- xah = list_entry(p, struct reiserfs_xattr_handler, handlers);
- if (xah->init) {
- err = xah->init();
- if (err) {
- list_del_init(p);
- break;
- }
+static int xattr_mount_check(struct super_block *s)
+{
+ /* We need generation numbers to ensure that the oid mapping is correct
+ * v3.5 filesystems don't have them. */
+ if (old_format_only(s)) {
+ if (reiserfs_xattrs_optional(s)) {
+ /* Old format filesystem, but optional xattrs have
+ * been enabled. Error out. */
+ reiserfs_warning(s, "jdm-2005",
+ "xattrs/ACLs not supported "
+ "on pre-v3.6 format filesystems. "
+ "Failing mount.");
+ return -EOPNOTSUPP;
}
}
- /* Clean up other handlers, if any failed */
- if (err)
- __unregister_handlers();
-
- write_unlock(&handler_lock);
- return err;
+ return 0;
}
-void reiserfs_xattr_unregister_handlers(void)
+int reiserfs_permission(struct inode *inode, int mask)
{
- write_lock(&handler_lock);
- __unregister_handlers();
- write_unlock(&handler_lock);
+ /*
+ * We don't do permission checks on the internal objects.
+ * Permissions are determined by the "owning" object.
+ */
+ if (IS_PRIVATE(inode))
+ return 0;
+
+#ifdef CONFIG_REISERFS_FS_XATTR
+ /*
+ * Stat data v1 doesn't support ACLs.
+ */
+ if (get_inode_sd_version(inode) != STAT_DATA_V1)
+ return generic_permission(inode, mask, reiserfs_check_acl);
+#endif
+ return generic_permission(inode, mask, NULL);
}
-/* This will catch lookups from the fs root to .reiserfs_priv */
-static int
-xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name)
+static int xattr_hide_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root;
- if (name->len == priv_root->d_name.len &&
- name->hash == priv_root->d_name.hash &&
- !memcmp(name->name, priv_root->d_name.name, name->len)) {
- return -ENOENT;
- } else if (q1->len == name->len &&
- !memcmp(q1->name, name->name, name->len))
- return 0;
- return 1;
+ return -EPERM;
}
-static struct dentry_operations xattr_lookup_poison_ops = {
- .d_compare = xattr_lookup_poison,
+static const struct dentry_operations xattr_lookup_poison_ops = {
+ .d_revalidate = xattr_hide_revalidate,
};
+int reiserfs_lookup_privroot(struct super_block *s)
+{
+ struct dentry *dentry;
+ int err = 0;
+
+ /* If we don't have the privroot located yet - go find it */
+ reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
+ dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
+ strlen(PRIVROOT_NAME));
+ if (!IS_ERR(dentry)) {
+ REISERFS_SB(s)->priv_root = dentry;
+ dentry->d_op = &xattr_lookup_poison_ops;
+ if (dentry->d_inode)
+ dentry->d_inode->i_flags |= S_PRIVATE;
+ } else
+ err = PTR_ERR(dentry);
+ mutex_unlock(&s->s_root->d_inode->i_mutex);
+
+ return err;
+}
+
/* We need to take a copy of the mount flags since things like
* MS_RDONLY don't get set until *after* we're called.
* mount_flags != mount_options */
int reiserfs_xattr_init(struct super_block *s, int mount_flags)
{
int err = 0;
+ struct dentry *privroot = REISERFS_SB(s)->priv_root;
- /* We need generation numbers to ensure that the oid mapping is correct
- * v3.5 filesystems don't have them. */
- if (!old_format_only(s)) {
- set_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
- } else if (reiserfs_xattrs_optional(s)) {
- /* Old format filesystem, but optional xattrs have been enabled
- * at mount time. Error out. */
- reiserfs_warning(s, "xattrs/ACLs not supported on pre v3.6 "
- "format filesystem. Failing mount.");
- err = -EOPNOTSUPP;
+ err = xattr_mount_check(s);
+ if (err)
goto error;
- } else {
- /* Old format filesystem, but no optional xattrs have been enabled. This
- * means we silently disable xattrs on the filesystem. */
- clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
+
+ if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) {
+ reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s);
+ err = create_privroot(REISERFS_SB(s)->priv_root);
+ mutex_unlock(&s->s_root->d_inode->i_mutex);
}
- /* If we don't have the privroot located yet - go find it */
- if (reiserfs_xattrs(s) && !REISERFS_SB(s)->priv_root) {
- struct dentry *dentry;
- dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
- strlen(PRIVROOT_NAME));
- if (!IS_ERR(dentry)) {
- if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) {
- struct inode *inode = dentry->d_parent->d_inode;
- down(&inode->i_sem);
- err = inode->i_op->mkdir(inode, dentry, 0700);
- up(&inode->i_sem);
- if (err) {
- dput(dentry);
- dentry = NULL;
- }
-
- if (dentry && dentry->d_inode)
- reiserfs_warning(s,
- "Created %s on %s - reserved for "
- "xattr storage.",
- PRIVROOT_NAME,
- reiserfs_bdevname
- (inode->i_sb));
- } else if (!dentry->d_inode) {
- dput(dentry);
- dentry = NULL;
- }
- } else
- err = PTR_ERR(dentry);
-
- if (!err && dentry) {
- s->s_root->d_op = &xattr_lookup_poison_ops;
- reiserfs_mark_inode_private(dentry->d_inode);
- REISERFS_SB(s)->priv_root = dentry;
- } else if (!(mount_flags & MS_RDONLY)) { /* xattrs are unavailable */
- /* If we're read-only it just means that the dir hasn't been
- * created. Not an error -- just no xattrs on the fs. We'll
- * check again if we go read-write */
- reiserfs_warning(s, "xattrs/ACLs enabled and couldn't "
- "find/create .reiserfs_priv. Failing mount.");
- err = -EOPNOTSUPP;
+ if (privroot->d_inode) {
+ s->s_xattr = reiserfs_xattr_handlers;
+ reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s);
+ if (!REISERFS_SB(s)->xattr_root) {
+ struct dentry *dentry;
+ dentry = lookup_one_len(XAROOT_NAME, privroot,
+ strlen(XAROOT_NAME));
+ if (!IS_ERR(dentry))
+ REISERFS_SB(s)->xattr_root = dentry;
+ else
+ err = PTR_ERR(dentry);
}
+ mutex_unlock(&privroot->d_inode->i_mutex);
}
- error:
- /* This is only nonzero if there was an error initializing the xattr
- * directory or if there is a condition where we don't support them. */
+error:
if (err) {
- clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt));
clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt));
clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt));
}
/* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
- s->s_flags = s->s_flags & ~MS_POSIXACL;
if (reiserfs_posixacl(s))
s->s_flags |= MS_POSIXACL;
+ else
+ s->s_flags &= ~MS_POSIXACL;
return err;
}
-
-static int
-__reiserfs_permission(struct inode *inode, int mask, struct nameidata *nd,
- int need_lock)
-{
- umode_t mode = inode->i_mode;
-
- if (mask & MAY_WRITE) {
- /*
- * Nobody gets write access to a read-only fs.
- */
- if (IS_RDONLY(inode) &&
- (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
- return -EROFS;
-
- /*
- * Nobody gets write access to an immutable file.
- */
- if (IS_IMMUTABLE(inode))
- return -EACCES;
- }
-
- /* We don't do permission checks on the internal objects.
- * Permissions are determined by the "owning" object. */
- if (is_reiserfs_priv_object(inode))
- return 0;
-
- if (current->fsuid == inode->i_uid) {
- mode >>= 6;
-#ifdef CONFIG_REISERFS_FS_POSIX_ACL
- } else if (reiserfs_posixacl(inode->i_sb) &&
- get_inode_sd_version(inode) != STAT_DATA_V1) {
- struct posix_acl *acl;
-
- /* ACL can't contain additional permissions if
- the ACL_MASK entry is 0 */
- if (!(mode & S_IRWXG))
- goto check_groups;
-
- if (need_lock) {
- reiserfs_read_lock_xattr_i(inode);
- reiserfs_read_lock_xattrs(inode->i_sb);
- }
- acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS);
- if (need_lock) {
- reiserfs_read_unlock_xattrs(inode->i_sb);
- reiserfs_read_unlock_xattr_i(inode);
- }
- if (IS_ERR(acl)) {
- if (PTR_ERR(acl) == -ENODATA)
- goto check_groups;
- return PTR_ERR(acl);
- }
-
- if (acl) {
- int err = posix_acl_permission(inode, acl, mask);
- posix_acl_release(acl);
- if (err == -EACCES) {
- goto check_capabilities;
- }
- return err;
- } else {
- goto check_groups;
- }
-#endif
- } else {
- check_groups:
- if (in_group_p(inode->i_gid))
- mode >>= 3;
- }
-
- /*
- * If the DACs are ok we don't need any capability check.
- */
- if (((mode & mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == mask))
- return 0;
-
- check_capabilities:
- /*
- * Read/write DACs are always overridable.
- * Executable DACs are overridable if at least one exec bit is set.
- */
- if (!(mask & MAY_EXEC) ||
- (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
- if (capable(CAP_DAC_OVERRIDE))
- return 0;
-
- /*
- * Searching includes executable on directories, else just read.
- */
- if (mask == MAY_READ || (S_ISDIR(inode->i_mode) && !(mask & MAY_WRITE)))
- if (capable(CAP_DAC_READ_SEARCH))
- return 0;
-
- return -EACCES;
-}
-
-int reiserfs_permission(struct inode *inode, int mask, struct nameidata *nd)
-{
- return __reiserfs_permission(inode, mask, nd, 1);
-}
-
-int
-reiserfs_permission_locked(struct inode *inode, int mask, struct nameidata *nd)
-{
- return __reiserfs_permission(inode, mask, nd, 0);
-}