[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/reiserfs/xattr.c b/ap/os/linux/linux-3.4.x/fs/reiserfs/xattr.c
new file mode 100644
index 0000000..048d990
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/reiserfs/xattr.c
@@ -0,0 +1,1021 @@
+/*
+ * linux/fs/reiserfs/xattr.c
+ *
+ * Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com>
+ *
+ */
+
+/*
+ * In order to implement EA/ACLs in a clean, backwards compatible manner,
+ * they are implemented as files in a "private" directory.
+ * Each EA is in it's own file, with the directory layout like so (/ is assumed
+ * to be relative to fs root). Inside the /.reiserfs_priv/xattrs directory,
+ * directories named using the capital-hex form of the objectid and
+ * generation number are used. Inside each directory are individual files
+ * named with the name of the extended attribute.
+ *
+ * So, for objectid 12648430, we could have:
+ * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_access
+ * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_default
+ * /.reiserfs_priv/xattrs/C0FFEE.0/user.Content-Type
+ * .. or similar.
+ *
+ * The file contents are the text of the EA. The size is known based on the
+ * stat data describing the file.
+ *
+ * In the case of system.posix_acl_access and system.posix_acl_default, since
+ * 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 "reiserfs.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 "xattr.h"
+#include "acl.h"
+#include <asm/uaccess.h>
+#include <net/checksum.h>
+#include <linux/stat.h>
+#include <linux/quotaops.h>
+#include <linux/security.h>
+
+#define PRIVROOT_NAME ".reiserfs_priv"
+#define XAROOT_NAME "xattrs"
+
+
+/* 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)
+{
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
+ return dir->i_op->create(dir, dentry, mode, NULL);
+}
+#endif
+
+static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+ BUG_ON(!mutex_is_locked(&dir->i_mutex));
+ return dir->i_op->mkdir(dir, dentry, mode);
+}
+
+/* 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)
+{
+ 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);
+ error = dir->i_op->unlink(dir, dentry);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+
+ if (!error)
+ d_delete(dentry);
+ return error;
+}
+
+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);
+ 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);
+
+ return error;
+}
+
+#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
+
+static struct dentry *open_xa_root(struct super_block *sb, int flags)
+{
+ 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);
+
+ 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);
+ }
+ }
+
+ mutex_unlock(&privroot->d_inode->i_mutex);
+ return xaroot;
+}
+
+static struct dentry *open_xa_dir(const struct inode *inode, int flags)
+{
+ struct dentry *xaroot, *xadir;
+ char namebuf[17];
+
+ xaroot = open_xa_root(inode->i_sb, flags);
+ if (IS_ERR(xaroot))
+ return xaroot;
+
+ snprintf(namebuf, sizeof(namebuf), "%X.%X",
+ le32_to_cpu(INODE_PKEY(inode)->k_objectid),
+ inode->i_generation);
+
+ 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);
+ xadir = ERR_PTR(err);
+ }
+ }
+
+ mutex_unlock(&xaroot->d_inode->i_mutex);
+ dput(xaroot);
+ return xadir;
+}
+
+/* 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];
+};
+
+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));
+
+ if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
+ return -ENOSPC;
+
+ if (name[0] == '.' && (namelen < 2 ||
+ (namelen == 2 && name[1] == '.')))
+ return 0;
+
+ 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;
+ }
+
+ dbuf->dentries[dbuf->count++] = dentry;
+ return 0;
+}
+
+static void
+cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
+{
+ int i;
+ for (i = 0; i < buf->count; i++)
+ if (buf->dentries[i])
+ dput(buf->dentries[i]);
+}
+
+static int reiserfs_for_each_xattr(struct inode *inode,
+ int (*action)(struct dentry *, void *),
+ void *data)
+{
+ struct dentry *dir;
+ int i, err = 0;
+ loff_t pos = 0;
+ struct reiserfs_dentry_buf buf = {
+ .count = 0,
+ };
+
+ /* Skip out, an xattr has no xattrs associated with it */
+ if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
+ return 0;
+
+ 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;
+ }
+
+ mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR);
+
+ reiserfs_write_lock(inode->i_sb);
+
+ buf.xadir = dir;
+ err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos);
+ while ((err == 0 || err == -ENOSPC) && buf.count) {
+ err = 0;
+
+ for (i = 0; i < buf.count && buf.dentries[i]; i++) {
+ int lerr = 0;
+ struct dentry *dentry = buf.dentries[i];
+
+ if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode))
+ lerr = action(dentry, data);
+
+ 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);
+
+ /* Clean up after a failed readdir */
+ cleanup_dentry_buf(&buf);
+
+ 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;
+}
+
+static int delete_one_xattr(struct dentry *dentry, void *data)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
+
+ /* This is the xattr dir, handle specially. */
+ if (S_ISDIR(dentry->d_inode->i_mode))
+ return xattr_rmdir(dir, dentry);
+
+ return xattr_unlink(dir, dentry);
+}
+
+static int chown_one_xattr(struct dentry *dentry, void *data)
+{
+ struct iattr *attrs = data;
+ return reiserfs_setattr(dentry, attrs);
+}
+
+/* No i_mutex, but the inode is unconnected. */
+int reiserfs_delete_xattrs(struct inode *inode)
+{
+ 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;
+ }
+
+ 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 */
+static inline void reiserfs_put_page(struct page *page)
+{
+ kunmap(page);
+ page_cache_release(page);
+}
+
+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 occurred - GFP_NOFS avoids this */
+ mapping_set_gfp_mask(mapping, GFP_NOFS);
+ page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL);
+ if (!IS_ERR(page)) {
+ kmap(page);
+ if (PageError(page))
+ goto fail;
+ }
+ return page;
+
+ fail:
+ reiserfs_put_page(page);
+ return ERR_PTR(-EIO);
+}
+
+static inline __u32 xattr_hash(const char *msg, int len)
+{
+ return csum_partial(msg, len, 0);
+}
+
+int reiserfs_commit_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 (inode_unhashed(inode) || !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_mutex: down
+ */
+int
+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 dentry *dentry;
+ struct page *page;
+ char *data;
+ size_t file_pos = 0;
+ size_t buffer_pos = 0;
+ size_t new_size;
+ __u32 xahash = 0;
+
+ if (get_inode_sd_version(inode) == STAT_DATA_V1)
+ return -EOPNOTSUPP;
+
+ reiserfs_write_unlock(inode->i_sb);
+
+ if (!buffer) {
+ err = lookup_and_delete_xattr(inode, name);
+ reiserfs_write_lock(inode->i_sb);
+ return err;
+ }
+
+ dentry = xattr_lookup(inode, name, flags);
+ if (IS_ERR(dentry)) {
+ reiserfs_write_lock(inode->i_sb);
+ return PTR_ERR(dentry);
+ }
+
+ down_write(&REISERFS_I(inode)->i_xattr_sem);
+
+ 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;
+ size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
+ if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
+ chunk = PAGE_CACHE_SIZE;
+ else
+ chunk = buffer_size - buffer_pos;
+
+ page = reiserfs_get_page(dentry->d_inode, file_pos);
+ if (IS_ERR(page)) {
+ err = PTR_ERR(page);
+ goto out_unlock;
+ }
+
+ lock_page(page);
+ data = page_address(page);
+
+ if (file_pos == 0) {
+ struct reiserfs_xattr_header *rxh;
+ skip = file_pos = sizeof(struct reiserfs_xattr_header);
+ if (chunk + skip > PAGE_CACHE_SIZE)
+ chunk = PAGE_CACHE_SIZE - skip;
+ rxh = (struct reiserfs_xattr_header *)data;
+ rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
+ rxh->h_hash = cpu_to_le32(xahash);
+ }
+
+ err = __reiserfs_write_begin(page, page_offset, chunk + skip);
+ if (!err) {
+ if (buffer)
+ memcpy(data + skip, buffer + buffer_pos, chunk);
+ err = reiserfs_commit_write(NULL, page, page_offset,
+ page_offset + chunk +
+ skip);
+ }
+ unlock_page(page);
+ reiserfs_put_page(page);
+ buffer_pos += chunk;
+ file_pos += chunk;
+ skip = 0;
+ if (err || buffer_size == 0 || !buffer)
+ break;
+ }
+
+ 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);
+ inode_dio_wait(dentry->d_inode);
+ reiserfs_write_lock(inode->i_sb);
+
+ err = reiserfs_setattr(dentry, &newattrs);
+ 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;
+ }
+
+ error = reiserfs_xattr_set_handle(&th, inode, name,
+ buffer, buffer_size, flags);
+
+ error2 = journal_end(&th, inode->i_sb, jbegin_count);
+ if (error == 0)
+ error = error2;
+ reiserfs_write_unlock(inode->i_sb);
+
+ return error;
+}
+
+/*
+ * inode->i_mutex: down
+ */
+int
+reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
+ size_t buffer_size)
+{
+ ssize_t err = 0;
+ struct dentry *dentry;
+ size_t isize;
+ size_t file_pos = 0;
+ size_t buffer_pos = 0;
+ struct page *page;
+ __u32 hash = 0;
+
+ if (name == NULL)
+ return -EINVAL;
+
+ /* We can't have xattrs attached to v1 items since they don't have
+ * generation numbers */
+ if (get_inode_sd_version(inode) == STAT_DATA_V1)
+ return -EOPNOTSUPP;
+
+ dentry = xattr_lookup(inode, name, XATTR_REPLACE);
+ if (IS_ERR(dentry)) {
+ err = PTR_ERR(dentry);
+ goto out;
+ }
+
+ 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_unlock;
+ }
+
+ if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
+ err = -ERANGE;
+ goto out_unlock;
+ }
+
+ while (file_pos < isize) {
+ size_t chunk;
+ char *data;
+ size_t skip = 0;
+ if (isize - file_pos > PAGE_CACHE_SIZE)
+ chunk = PAGE_CACHE_SIZE;
+ else
+ chunk = isize - file_pos;
+
+ page = reiserfs_get_page(dentry->d_inode, file_pos);
+ if (IS_ERR(page)) {
+ err = PTR_ERR(page);
+ goto out_unlock;
+ }
+
+ lock_page(page);
+ data = page_address(page);
+ if (file_pos == 0) {
+ struct reiserfs_xattr_header *rxh =
+ (struct reiserfs_xattr_header *)data;
+ skip = file_pos = sizeof(struct reiserfs_xattr_header);
+ chunk -= skip;
+ /* Magic doesn't match up.. */
+ if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
+ unlock_page(page);
+ reiserfs_put_page(page);
+ reiserfs_warning(inode->i_sb, "jdm-20001",
+ "Invalid magic for xattr (%s) "
+ "associated with %k", name,
+ INODE_PKEY(inode));
+ err = -EIO;
+ goto out_unlock;
+ }
+ hash = le32_to_cpu(rxh->h_hash);
+ }
+ memcpy(buffer + buffer_pos, data + skip, chunk);
+ unlock_page(page);
+ reiserfs_put_page(page);
+ file_pos += chunk;
+ buffer_pos += chunk;
+ skip = 0;
+ }
+ err = isize - sizeof(struct reiserfs_xattr_header);
+
+ if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
+ hash) {
+ reiserfs_warning(inode->i_sb, "jdm-20002",
+ "Invalid hash for xattr (%s) associated "
+ "with %k", name, INODE_PKEY(inode));
+ err = -EIO;
+ }
+
+out_unlock:
+ up_read(&REISERFS_I(inode)->i_xattr_sem);
+ dput(dentry);
+
+out:
+ 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)++)
+
+/* This is the implementation for the xattr plugin infrastructure */
+static inline const struct xattr_handler *
+find_xattr_handler_prefix(const struct xattr_handler **handlers,
+ const char *name)
+{
+ const struct xattr_handler *xah;
+
+ if (!handlers)
+ return NULL;
+
+ for_each_xattr_handler(handlers, xah) {
+ if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0)
+ break;
+ }
+
+ return xah;
+}
+
+
+/*
+ * Inode operation getxattr()
+ */
+ssize_t
+reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
+ size_t size)
+{
+ const struct xattr_handler *handler;
+
+ 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;
+
+ return handler->get(dentry, name, buffer, size, handler->flags);
+}
+
+/*
+ * Inode operation setxattr()
+ *
+ * dentry->d_inode->i_mutex down
+ */
+int
+reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+ size_t size, int flags)
+{
+ const struct xattr_handler *handler;
+
+ 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;
+
+ return handler->set(dentry, name, value, size, flags, handler->flags);
+}
+
+/*
+ * Inode operation removexattr()
+ *
+ * dentry->d_inode->i_mutex down
+ */
+int reiserfs_removexattr(struct dentry *dentry, const char *name)
+{
+ const struct xattr_handler *handler;
+ 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;
+
+ return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
+}
+
+struct listxattr_buf {
+ size_t size;
+ size_t pos;
+ char *buf;
+ struct dentry *dentry;
+};
+
+static int listxattr_filler(void *buf, const char *name, int namelen,
+ loff_t offset, u64 ino, unsigned int d_type)
+{
+ struct listxattr_buf *b = (struct listxattr_buf *)buf;
+ size_t size;
+ if (name[0] != '.' ||
+ (namelen != 1 && (name[1] != '.' || namelen != 2))) {
+ const 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()
+ *
+ * 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 dentry *dir;
+ int err = 0;
+ loff_t pos = 0;
+ struct listxattr_buf buf = {
+ .dentry = dentry,
+ .buf = buffer,
+ .size = buffer ? size : 0,
+ };
+
+ if (!dentry->d_inode)
+ return -EINVAL;
+
+ if (!dentry->d_sb->s_xattr ||
+ get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
+ return -EOPNOTSUPP;
+
+ 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;
+ }
+
+ 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);
+
+ if (!err)
+ err = buf.pos;
+
+ dput(dir);
+out:
+ return err;
+}
+
+static int create_privroot(struct dentry *dentry)
+{
+ 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;
+ }
+
+ dentry->d_inode->i_flags |= S_PRIVATE;
+ reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
+ "storage.\n", PRIVROOT_NAME);
+
+ 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
+
+/* Actual operations that are exported to VFS-land */
+const 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
+ &reiserfs_xattr_security_handler,
+#endif
+#ifdef CONFIG_REISERFS_FS_POSIX_ACL
+ &reiserfs_posix_acl_access_handler,
+ &reiserfs_posix_acl_default_handler,
+#endif
+ NULL
+};
+
+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;
+ }
+ }
+
+ return 0;
+}
+
+int reiserfs_permission(struct inode *inode, int mask)
+{
+ /*
+ * We don't do permission checks on the internal objects.
+ * Permissions are determined by the "owning" object.
+ */
+ if (IS_PRIVATE(inode))
+ return 0;
+
+ return generic_permission(inode, mask);
+}
+
+static int xattr_hide_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+ return -EPERM;
+}
+
+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;
+ d_set_d_op(dentry, &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;
+
+ err = xattr_mount_check(s);
+ if (err)
+ goto error;
+
+ 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 (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:
+ if (err) {
+ 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. */
+ if (reiserfs_posixacl(s))
+ s->s_flags |= MS_POSIXACL;
+ else
+ s->s_flags &= ~MS_POSIXACL;
+
+ return err;
+}