gfs2: use generic posix ACL infrastructure

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>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/gfs2/acl.c

@@ -49,10 +49,6 @@ struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
 	if (!ip->i_eattr)
 		return NULL;
 
-	acl = get_cached_acl(&ip->i_inode, type);
-	if (acl != ACL_NOT_CACHED)
-		return acl;
-
 	name = gfs2_acl_name(type);
 	if (name == NULL)
 		return ERR_PTR(-EINVAL);
@@ -80,7 +76,7 @@ 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 +84,49 @@ 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)
+			return error;
 
-		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,
-};
-

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__ */

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, inode->i_mode);
+	}
 
 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,
 };
 
@@ -1877,6 +1900,5 @@ const struct inode_operations gfs2_symlink_iops = {
 	.listxattr = gfs2_listxattr,
 	.removexattr = gfs2_removexattr,
 	.fiemap = gfs2_fiemap,
-	.get_acl = gfs2_get_acl,
 };
 

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,
 };