[PATCH 16/18] gfs2: use generic posix ACL infrastructure

Christoph Hellwig
2013-12-01T12:07:14Z

[-- Attachment #1: 0016-gfs2-use-generic-posix-ACL-infrastructure.patch --]
[-- Type: text/plain, Size: 10351 bytes --]

This contains some major refactoring for the create path so that
inodes are created with the right mode to start with instead of
fixing it up later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/gfs2/acl.c | 229 +++++++------------------------------------------------
fs/gfs2/acl.h | 4 +-
fs/gfs2/inode.c | 33 ++++++--
fs/gfs2/xattr.c | 4 +-
4 files changed, 61 insertions(+), 209 deletions(-)

diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index e82e4ac..e6c7a2c 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -80,7 +80,7 @@ static int gfs2_set_mode(struct inode *inode, umode_t mode)
return error;
}

-static int gfs2_acl_set(struct inode *inode, int type, struct posix_acl *acl)
+int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
int error;
int len;
@@ -88,219 +88,48 @@ static int gfs2_acl_set(struct inode *inode, int type, struct posix_acl *acl)
const char *name = gfs2_acl_name(type);

BUG_ON(name == NULL);
- len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
- if (len == 0)
- return 0;
- data = kmalloc(len, GFP_NOFS);
- if (data == NULL)
- return -ENOMEM;
- error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
- if (error < 0)
- goto out;
- error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
- if (!error)
- set_cached_acl(inode, type, acl);
-out:
- kfree(data);
- return error;
-}
-
-int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode)
-{
- struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
- struct posix_acl *acl;
- umode_t mode = inode->i_mode;
- int error = 0;
-
- if (!sdp->sd_args.ar_posix_acl)
- return 0;
- if (S_ISLNK(inode->i_mode))
- return 0;
-
- acl = gfs2_get_acl(&dip->i_inode, ACL_TYPE_DEFAULT);
- if (IS_ERR(acl))
- return PTR_ERR(acl);
- if (!acl) {
- mode &= ~current_umask();
- return gfs2_set_mode(inode, mode);
- }
-
- if (S_ISDIR(inode->i_mode)) {
- error = gfs2_acl_set(inode, ACL_TYPE_DEFAULT, acl);
- if (error)
- goto out;
- }
-
- error = __posix_acl_create(&acl, GFP_NOFS, &mode);
- if (error < 0)
- return error;
-
- if (error == 0)
- goto munge;
-
- error = gfs2_acl_set(inode, ACL_TYPE_ACCESS, acl);
- if (error)
- goto out;
-munge:
- error = gfs2_set_mode(inode, mode);
-out:
- posix_acl_release(acl);
- return error;
-}
-
-int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr)
-{
- struct inode *inode = &ip->i_inode;
- struct posix_acl *acl;
- char *data;
- unsigned int len;
- int error;
-
- acl = gfs2_get_acl(&ip->i_inode, ACL_TYPE_ACCESS);
- if (IS_ERR(acl))
- return PTR_ERR(acl);
- if (!acl)
- return gfs2_setattr_simple(inode, attr);
-
- error = __posix_acl_chmod(&acl, GFP_NOFS, attr->ia_mode);
- if (error)
- return error;
-
- len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
- data = kmalloc(len, GFP_NOFS);
- error = -ENOMEM;
- if (data == NULL)
- goto out;
- posix_acl_to_xattr(&init_user_ns, acl, data, len);
- error = gfs2_xattr_acl_chmod(ip, attr, data);
- kfree(data);
- set_cached_acl(&ip->i_inode, ACL_TYPE_ACCESS, acl);
-
-out:
- posix_acl_release(acl);
- return error;
-}
-
-static int gfs2_acl_type(const char *name)
-{
- if (strcmp(name, GFS2_POSIX_ACL_ACCESS) == 0)
- return ACL_TYPE_ACCESS;
- if (strcmp(name, GFS2_POSIX_ACL_DEFAULT) == 0)
- return ACL_TYPE_DEFAULT;
- return -EINVAL;
-}
-
-static int gfs2_xattr_system_get(struct dentry *dentry, const char *name,
- void *buffer, size_t size, int xtype)
-{
- struct inode *inode = dentry->d_inode;
- struct gfs2_sbd *sdp = GFS2_SB(inode);
- struct posix_acl *acl;
- int type;
- int error;
-
- if (!sdp->sd_args.ar_posix_acl)
- return -EOPNOTSUPP;
-
- type = gfs2_acl_type(name);
- if (type < 0)
- return type;
-
- acl = gfs2_get_acl(inode, type);
- if (IS_ERR(acl))
- return PTR_ERR(acl);
- if (acl == NULL)
- return -ENODATA;
-
- error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
- posix_acl_release(acl);
-
- return error;
-}
-
-static int gfs2_xattr_system_set(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags,
- int xtype)
-{
- struct inode *inode = dentry->d_inode;
- struct gfs2_sbd *sdp = GFS2_SB(inode);
- struct posix_acl *acl = NULL;
- int error = 0, type;
-
- if (!sdp->sd_args.ar_posix_acl)
- return -EOPNOTSUPP;
-
- type = gfs2_acl_type(name);
- if (type < 0)
- return type;
- if (flags & XATTR_CREATE)
- return -EINVAL;
- if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
- return value ? -EACCES : 0;
- if (!uid_eq(current_fsuid(), inode->i_uid) && !capable(CAP_FOWNER))
- return -EPERM;
- if (S_ISLNK(inode->i_mode))
- return -EOPNOTSUPP;
-
- if (!value)
- goto set_acl;

- acl = posix_acl_from_xattr(&init_user_ns, value, size);
- if (!acl) {
- /*
- * acl_set_file(3) may request that we set default ACLs with
- * zero length -- defend (gracefully) against that here.
- */
- goto out;
- }
- if (IS_ERR(acl)) {
- error = PTR_ERR(acl);
- goto out;
- }
-
- error = posix_acl_valid(acl);
- if (error)
- goto out_release;
-
- error = -EINVAL;
if (acl->a_count > GFS2_ACL_MAX_ENTRIES)
- goto out_release;
+ return -EINVAL;

if (type == ACL_TYPE_ACCESS) {
umode_t mode = inode->i_mode;
+
error = posix_acl_equiv_mode(acl, &mode);
+ if (error < 0)

- if (error <= 0) {
- posix_acl_release(acl);
+ if (error == 0)
acl = NULL;

- if (error < 0)
- return error;
- }
-
error = gfs2_set_mode(inode, mode);
if (error)
- goto out_release;
+ return error;
}

-set_acl:
- error = __gfs2_xattr_set(inode, name, value, size, 0, GFS2_EATYPE_SYS);
- if (!error) {
- if (acl)
- set_cached_acl(inode, type, acl);
- else
- forget_cached_acl(inode, type);
+ if (acl) {
+ len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
+ if (len == 0)
+ return 0;
+ data = kmalloc(len, GFP_NOFS);
+ if (data == NULL)
+ return -ENOMEM;
+ error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
+ if (error < 0)
+ goto out;
+ } else {
+ data = NULL;
+ len = 0;
}
-out_release:
- posix_acl_release(acl);
+
+ error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
+ if (error)
+ goto out;
+
+ if (acl)
+ set_cached_acl(inode, type, acl);
+ else
+ forget_cached_acl(inode, type);
out:
+ kfree(data);
return error;
}
-
-const struct xattr_handler gfs2_xattr_system_handler = {
- .prefix = XATTR_SYSTEM_PREFIX,
- .flags = GFS2_EATYPE_SYS,
- .get = gfs2_xattr_system_get,
- .set = gfs2_xattr_system_set,
-};
-
diff --git a/fs/gfs2/acl.h b/fs/gfs2/acl.h
index 0da38dc..301260c 100644
--- a/fs/gfs2/acl.h
+++ b/fs/gfs2/acl.h
@@ -17,8 +17,6 @@
#define GFS2_ACL_MAX_ENTRIES 25

extern struct posix_acl *gfs2_get_acl(struct inode *inode, int type);
-extern int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode);
-extern int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr);
-extern const struct xattr_handler gfs2_xattr_system_handler;
+extern int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type);

#endif /* __ACL_DOT_H__ */
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 7119504..92b4ec0 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -552,6 +552,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
unsigned int size, int excl, int *opened)
{
const struct qstr *name = &dentry->d_name;
+ struct posix_acl *default_acl, *acl;
struct gfs2_holder ghs[2];
struct inode *inode = NULL;
struct gfs2_inode *dip = GFS2_I(dir), *ip;
@@ -611,10 +612,14 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
if (!inode)
goto fail_gunlock;

+ error = posix_acl_create(dir, &mode, &default_acl, &acl);
+ if (error)
+ goto fail_free_vfs_inode;
+
ip = GFS2_I(inode);
error = gfs2_rs_alloc(ip);
if (error)
- goto fail_free_inode;
+ goto fail_free_acls;

inode->i_mode = mode;
set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
@@ -682,7 +687,16 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
gfs2_set_iop(inode);
insert_inode_hash(inode);

- error = gfs2_acl_create(dip, inode);
+ if (default_acl) {
+ error = gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
+ posix_acl_release(default_acl);
+ }
+ if (acl) {
+ if (!error)
+ error = gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
+ posix_acl_release(acl);
+ }
+
if (error)
goto fail_gunlock3;

@@ -716,6 +730,12 @@ fail_free_inode:
if (ip->i_gl)
gfs2_glock_put(ip->i_gl);
gfs2_rs_delete(ip, NULL);
+fail_free_acls:
+ if (default_acl)
+ posix_acl_release(default_acl);
+ if (acl)
+ posix_acl_release(acl);
+fail_free_vfs_inode:
free_inode_nonrcu(inode);
inode = NULL;
fail_gunlock:
@@ -1678,10 +1698,11 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
error = gfs2_setattr_size(inode, attr->ia_size);
else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
error = setattr_chown(inode, attr);
- else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
- error = gfs2_acl_chmod(ip, attr);
- else
+ else {
error = gfs2_setattr_simple(inode, attr);
+ if (!error && attr->ia_valid & ATTR_MODE)
+ error = posix_acl_chmod(inode);
+ }

out:
if (!error)
@@ -1841,6 +1862,7 @@ const struct inode_operations gfs2_file_iops = {
.removexattr = gfs2_removexattr,
.fiemap = gfs2_fiemap,
.get_acl = gfs2_get_acl,
+ .set_acl = gfs2_set_acl,
};

const struct inode_operations gfs2_dir_iops = {
@@ -1862,6 +1884,7 @@ const struct inode_operations gfs2_dir_iops = {
.removexattr = gfs2_removexattr,
.fiemap = gfs2_fiemap,
.get_acl = gfs2_get_acl,
+ .set_acl = gfs2_set_acl,
.atomic_open = gfs2_atomic_open,
};

diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 8c6a6f6..0b81f78 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -13,6 +13,7 @@
#include <linux/buffer_head.h>
#include <linux/xattr.h>
#include <linux/gfs2_ondisk.h>
+#include <linux/posix_acl_xattr.h>
#include <asm/uaccess.h>

#include "gfs2.h"
@@ -1500,7 +1501,8 @@ static const struct xattr_handler gfs2_xattr_security_handler = {
const struct xattr_handler *gfs2_xattr_handlers[] = {
&gfs2_xattr_user_handler,
&gfs2_xattr_security_handler,
- &gfs2_xattr_system_handler,
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
NULL,
};

--
1.7.10.4