From fdebe2bd70047e057827cba85ba31b2545e31900 Mon Sep 17 00:00:00 2001 From: Yan Date: Mon, 14 Jan 2008 13:26:08 -0500 Subject: [PATCH] Btrfs: Add readonly inode flag This patch adds readonly inode flag support. A file with this flag can't be modified, but can be deleted. Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 6 +++--- fs/btrfs/inode.c | 16 ++++++++++++---- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 0c0edacbc14c..245952cf7650 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -451,9 +451,9 @@ struct btrfs_root { /* * Inode flags */ -#define BTRFS_INODE_NODATASUM 0x1 -#define BTRFS_INODE_NODATACOW 0x2 - +#define BTRFS_INODE_NODATASUM (1 << 0) +#define BTRFS_INODE_NODATACOW (1 << 1) +#define BTRFS_INODE_READONLY (1 << 2) #define btrfs_clear_flag(inode, flag) (BTRFS_I(inode)->flags &= \ ~BTRFS_INODE_##flag) #define btrfs_set_flag(inode, flag) (BTRFS_I(inode)->flags |= \ diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index fba0478a95f4..fd0e0d80333b 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2850,6 +2850,13 @@ out_fail: btrfs_throttle(root); return err; } +static int btrfs_permission(struct inode *inode, int mask, + struct nameidata *nd) +{ + if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE)) + return -EACCES; + return generic_permission(inode, mask, NULL); +} static struct inode_operations btrfs_dir_inode_operations = { .lookup = btrfs_lookup, @@ -2866,12 +2873,12 @@ static struct inode_operations btrfs_dir_inode_operations = { .getxattr = generic_getxattr, .listxattr = btrfs_listxattr, .removexattr = generic_removexattr, + .permission = btrfs_permission, }; - static struct inode_operations btrfs_dir_ro_inode_operations = { .lookup = btrfs_lookup, + .permission = btrfs_permission, }; - static struct file_operations btrfs_dir_file_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, @@ -2916,15 +2923,16 @@ static struct inode_operations btrfs_file_inode_operations = { .getxattr = generic_getxattr, .listxattr = btrfs_listxattr, .removexattr = generic_removexattr, + .permission = btrfs_permission, }; - static struct inode_operations btrfs_special_inode_operations = { .getattr = btrfs_getattr, .setattr = btrfs_setattr, + .permission = btrfs_permission, }; - static struct inode_operations btrfs_symlink_inode_operations = { .readlink = generic_readlink, .follow_link = page_follow_link_light, .put_link = page_put_link, + .permission = btrfs_permission, }; -- 2.39.2