[PATCH 15/18] jfs: use generic posix ACL infrastructure

Christoph Hellwig
2013-12-01T12:07:13Z

[-- Attachment #1: 0015-jfs-use-generic-posix-ACL-infrastructure.patch --]
[-- Type: text/plain, Size: 11751 bytes --]

Copy the scheme I introduced to btrfs many years ago to only use the
xattr handler for ACLs, but pass plain attrs straight through.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/jfs/acl.c | 105 ++++++++++++++++++++------------------------------
fs/jfs/file.c | 4 +-
fs/jfs/jfs_acl.h | 7 +---
fs/jfs/jfs_xattr.h | 2 +
fs/jfs/namei.c | 1 +
fs/jfs/super.c | 2 +
fs/jfs/xattr.c | 108 ++++++++++++++++++----------------------------------
7 files changed, 89 insertions(+), 140 deletions(-)

diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 28d529a..e973b85 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -72,7 +72,7 @@ struct posix_acl *jfs_get_acl(struct inode *inode, int type)
return acl;
}

-static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
+static int __jfs_set_acl(tid_t tid, struct inode *inode, int type,
struct posix_acl *acl)
{
char *ea_name;
@@ -80,21 +80,22 @@ static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
int size = 0;
char *value = NULL;

- if (S_ISLNK(inode->i_mode))
- return -EOPNOTSUPP;
-
- switch(type) {
- case ACL_TYPE_ACCESS:
- ea_name = POSIX_ACL_XATTR_ACCESS;
- break;
- case ACL_TYPE_DEFAULT:
- ea_name = POSIX_ACL_XATTR_DEFAULT;
- if (!S_ISDIR(inode->i_mode))
- return acl ? -EACCES : 0;
- break;
- default:
- return -EINVAL;
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ ea_name = POSIX_ACL_XATTR_ACCESS;
+ rc = posix_acl_equiv_mode(acl, &inode->i_mode);
+ if (rc < 0)
+ return rc;
+ if (rc == 0)
+ acl = NULL;
+ break;
+ case ACL_TYPE_DEFAULT:
+ ea_name = POSIX_ACL_XATTR_DEFAULT;
+ break;
+ default:
+ return -EINVAL;
}
+
if (acl) {
size = posix_acl_xattr_size(acl->a_count);
value = kmalloc(size, GFP_KERNEL);
@@ -114,65 +115,43 @@ out:
return rc;
}

+int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+{
+ int rc;
+ tid_t tid;
+
+ tid = txBegin(inode->i_sb, 0);
+ mutex_lock(&JFS_IP(inode)->commit_mutex);
+ rc = __jfs_set_acl(tid, inode, type, acl);
+ if (!rc)
+ rc = txCommit(tid, 1, &inode, 0);
+ txEnd(tid);
+ mutex_unlock(&JFS_IP(inode)->commit_mutex);
+ return rc;
+}
+
int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
{
- struct posix_acl *acl = NULL;
+ struct posix_acl *default_acl, *acl;
int rc = 0;

- if (S_ISLNK(inode->i_mode))
- return 0;
+ rc = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
+ if (rc)
+ return rc;

- acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT);
- if (IS_ERR(acl))
- return PTR_ERR(acl);
+ if (default_acl) {
+ rc = __jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, default_acl);
+ posix_acl_release(default_acl);
+ }

if (acl) {
- if (S_ISDIR(inode->i_mode)) {
- rc = jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, acl);
- if (rc)
- goto cleanup;
- }
- rc = __posix_acl_create(&acl, GFP_KERNEL, &inode->i_mode);
- if (rc < 0)
- goto cleanup; /* posix_acl_release(NULL) is no-op */
- if (rc > 0)
- rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
-cleanup:
+ if (!rc)
+ rc = __jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
posix_acl_release(acl);
- } else
- inode->i_mode &= ~current_umask();
+ }

JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
inode->i_mode;

return rc;
}
-
-int jfs_acl_chmod(struct inode *inode)
-{
- struct posix_acl *acl;
- int rc;
- tid_t tid;
-
- if (S_ISLNK(inode->i_mode))
- return -EOPNOTSUPP;
-
- acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
- if (IS_ERR(acl) || !acl)
- return PTR_ERR(acl);
-
- rc = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
- if (rc)
- return rc;
-
- tid = txBegin(inode->i_sb, 0);
- mutex_lock(&JFS_IP(inode)->commit_mutex);
- rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, acl);
- if (!rc)
- rc = txCommit(tid, 1, &inode, 0);
- txEnd(tid);
- mutex_unlock(&JFS_IP(inode)->commit_mutex);
-
- posix_acl_release(acl);
- return rc;
-}
diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index dd7442c..145a17e 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
@@ -19,6 +19,7 @@

#include <linux/mm.h>
#include <linux/fs.h>
+#include <linux/posix_acl.h>
#include <linux/quotaops.h>
#include "jfs_incore.h"
#include "jfs_inode.h"
@@ -131,7 +132,7 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
mark_inode_dirty(inode);

if (iattr->ia_valid & ATTR_MODE)
- rc = jfs_acl_chmod(inode);
+ rc = posix_acl_chmod(inode);
return rc;
}

@@ -143,6 +144,7 @@ const struct inode_operations jfs_file_inode_operations = {
.setattr = jfs_setattr,
#ifdef CONFIG_JFS_POSIX_ACL
.get_acl = jfs_get_acl,
+ .set_acl = jfs_set_acl,
#endif
};

diff --git a/fs/jfs/jfs_acl.h b/fs/jfs/jfs_acl.h
index ad84fe5..489f993 100644
--- a/fs/jfs/jfs_acl.h
+++ b/fs/jfs/jfs_acl.h
@@ -21,8 +21,8 @@
#ifdef CONFIG_JFS_POSIX_ACL

struct posix_acl *jfs_get_acl(struct inode *inode, int type);
+int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
int jfs_init_acl(tid_t, struct inode *, struct inode *);
-int jfs_acl_chmod(struct inode *inode);

#else

@@ -32,10 +32,5 @@ static inline int jfs_init_acl(tid_t tid, struct inode *inode,
return 0;
}

-static inline int jfs_acl_chmod(struct inode *inode)
-{
- return 0;
-}
-
#endif
#endif /* _H_JFS_ACL */
diff --git a/fs/jfs/jfs_xattr.h b/fs/jfs/jfs_xattr.h
index e9e100f..e8d717d 100644
--- a/fs/jfs/jfs_xattr.h
+++ b/fs/jfs/jfs_xattr.h
@@ -61,6 +61,8 @@ extern ssize_t jfs_getxattr(struct dentry *, const char *, void *, size_t);
extern ssize_t jfs_listxattr(struct dentry *, char *, size_t);
extern int jfs_removexattr(struct dentry *, const char *);

+extern const struct xattr_handler *jfs_xattr_handlers[];
+
#ifdef CONFIG_JFS_SECURITY
extern int jfs_init_security(tid_t, struct inode *, struct inode *,
const struct qstr *);
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index aa8a337..d59c7de 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -1524,6 +1524,7 @@ const struct inode_operations jfs_dir_inode_operations = {
.setattr = jfs_setattr,
#ifdef CONFIG_JFS_POSIX_ACL
.get_acl = jfs_get_acl,
+ .set_acl = jfs_set_acl,
#endif
};

diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 6669aa2..e2b7483 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -44,6 +44,7 @@
#include "jfs_imap.h"
#include "jfs_acl.h"
#include "jfs_debug.h"
+#include "jfs_xattr.h"

MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
@@ -522,6 +523,7 @@ static int jfs_fill_super(struct super_block *sb, void *data, int silent)
*/
sb->s_op = &jfs_super_operations;
sb->s_export_op = &jfs_export_operations;
+ sb->s_xattr = jfs_xattr_handlers;
#ifdef CONFIG_QUOTA
sb->dq_op = &dquot_operations;
sb->s_qcop = &dquot_quotactl_ops;
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index d3472f4..5324e4e 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -666,81 +666,12 @@ static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
}

/*
- * can_set_system_xattr
- *
- * This code is specific to the system.* namespace. It contains policy
- * which doesn't belong in the main xattr codepath.
- */
-static int can_set_system_xattr(struct inode *inode, const char *name,
- const void *value, size_t value_len)
-{
-#ifdef CONFIG_JFS_POSIX_ACL
- struct posix_acl *acl;
- int rc;
-
- if (!inode_owner_or_capable(inode))
- return -EPERM;
-
- /*
- * POSIX_ACL_XATTR_ACCESS is tied to i_mode
- */
- if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0) {
- acl = posix_acl_from_xattr(&init_user_ns, value, value_len);
- if (IS_ERR(acl)) {
- rc = PTR_ERR(acl);
- printk(KERN_ERR "posix_acl_from_xattr returned %d\n",
- rc);
- return rc;
- }
- if (acl) {
- rc = posix_acl_equiv_mode(acl, &inode->i_mode);
- posix_acl_release(acl);
- if (rc < 0) {
- printk(KERN_ERR
- "posix_acl_equiv_mode returned %d\n",
- rc);
- return rc;
- }
- mark_inode_dirty(inode);
- }
- /*
- * We're changing the ACL. Get rid of the cached one
- */
- forget_cached_acl(inode, ACL_TYPE_ACCESS);
-
- return 0;
- } else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0) {
- acl = posix_acl_from_xattr(&init_user_ns, value, value_len);
- if (IS_ERR(acl)) {
- rc = PTR_ERR(acl);
- printk(KERN_ERR "posix_acl_from_xattr returned %d\n",
- rc);
- return rc;
- }
- posix_acl_release(acl);
-
- /*
- * We're changing the default ACL. Get rid of the cached one
- */
- forget_cached_acl(inode, ACL_TYPE_DEFAULT);
-
- return 0;
- }
-#endif /* CONFIG_JFS_POSIX_ACL */
- return -EOPNOTSUPP;
-}
-
-/*
* Most of the permission checking is done by xattr_permission in the vfs.
- * The local file system is responsible for handling the system.* namespace.
* We also need to verify that this is a namespace that we recognize.
*/
static int can_set_xattr(struct inode *inode, const char *name,
const void *value, size_t value_len)
{
- if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
- return can_set_system_xattr(inode, name, value, value_len);
-
if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) {
/*
* This makes sure that we aren't trying to set an
@@ -748,7 +679,7 @@ static int can_set_xattr(struct inode *inode, const char *name,
* with "os2."
*/
if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN))
- return -EOPNOTSUPP;
+ return -EOPNOTSUPP;
return 0;
}

@@ -913,6 +844,14 @@ int jfs_setxattr(struct dentry *dentry, const char *name, const void *value,
if ((rc = can_set_xattr(inode, name, value, value_len)))
return rc;

+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_setxattr(dentry, name, value, value_len, flags);
+
if (value == NULL) { /* empty EA, do not remove */
value = "";
value_len = 0;
@@ -986,6 +925,14 @@ ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data,
{
int err;

+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_getxattr(dentry, name, data, buf_size);
+
if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
/*
* skip past "os2." prefix
@@ -1077,6 +1024,14 @@ int jfs_removexattr(struct dentry *dentry, const char *name)
if ((rc = can_set_xattr(inode, name, NULL, 0)))
return rc;

+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_removexattr(dentry, name);
+
tid = txBegin(inode->i_sb, 0);
mutex_lock(&ji->commit_mutex);
rc = __jfs_setxattr(tid, dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
@@ -1088,6 +1043,19 @@ int jfs_removexattr(struct dentry *dentry, const char *name)
return rc;
}

+/*
+ * List of handlers for synthetic system.* attributes. All real ondisk
+ * attributes are handled directly.
+ */
+const struct xattr_handler *jfs_xattr_handlers[] = {
+#ifdef JFS_POSIX_ACL
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+#endif
+ NULL,
+};
+
+
#ifdef CONFIG_JFS_SECURITY
static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
void *fs_info)
--
1.7.10.4