diff options
Diffstat (limited to 'fs/xfs/xfs_inode.c')
| -rw-r--r-- | fs/xfs/xfs_inode.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index d6635d219527..e8845287debd 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -925,6 +925,81 @@ xfs_bumplink( xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); } +#ifdef CONFIG_XFS_LIVE_HOOKS +/* + * Use a static key here to reduce the overhead of directory live update hooks. + * If the compiler supports jump labels, the static branch will be replaced by + * a nop sled when there are no hook users. Online fsck is currently the only + * caller, so this is a reasonable tradeoff. + * + * Note: Patching the kernel code requires taking the cpu hotplug lock. Other + * parts of the kernel allocate memory with that lock held, which means that + * XFS callers cannot hold any locks that might be used by memory reclaim or + * writeback when calling the static_branch_{inc,dec} functions. + */ +DEFINE_STATIC_XFS_HOOK_SWITCH(xfs_dir_hooks_switch); + +void +xfs_dir_hook_disable(void) +{ + xfs_hooks_switch_off(&xfs_dir_hooks_switch); +} + +void +xfs_dir_hook_enable(void) +{ + xfs_hooks_switch_on(&xfs_dir_hooks_switch); +} + +/* Call hooks for a directory update relating to a child dirent update. */ +inline void +xfs_dir_update_hook( + struct xfs_inode *dp, + struct xfs_inode *ip, + int delta, + const struct xfs_name *name) +{ + if (xfs_hooks_switched_on(&xfs_dir_hooks_switch)) { + struct xfs_dir_update_params p = { + .dp = dp, + .ip = ip, + .delta = delta, + .name = name, + }; + struct xfs_mount *mp = ip->i_mount; + + xfs_hooks_call(&mp->m_dir_update_hooks, 0, &p); + } +} + +/* Call the specified function during a directory update. */ +int +xfs_dir_hook_add( + struct xfs_mount *mp, + struct xfs_dir_hook *hook) +{ + return xfs_hooks_add(&mp->m_dir_update_hooks, &hook->dirent_hook); +} + +/* Stop calling the specified function during a directory update. */ +void +xfs_dir_hook_del( + struct xfs_mount *mp, + struct xfs_dir_hook *hook) +{ + xfs_hooks_del(&mp->m_dir_update_hooks, &hook->dirent_hook); +} + +/* Configure directory update hook functions. */ +void +xfs_dir_hook_setup( + struct xfs_dir_hook *hook, + notifier_fn_t mod_fn) +{ + xfs_hook_setup(&hook->dirent_hook, mod_fn); +} +#endif /* CONFIG_XFS_LIVE_HOOKS */ + int xfs_create( struct mnt_idmap *idmap, @@ -1036,6 +1111,12 @@ xfs_create( } /* + * Create ip with a reference from dp, and add '.' and '..' references + * if it's a directory. + */ + xfs_dir_update_hook(dp, ip, 1, name); + + /* * If this is a synchronous mount, make sure that the * create transaction goes to disk before returning to * the user. @@ -1249,6 +1330,7 @@ xfs_link( xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE); xfs_bumplink(tp, sip); + xfs_dir_update_hook(tdp, sip, 1, target_name); /* * If this is a synchronous mount, make sure that the @@ -2563,6 +2645,12 @@ xfs_remove( } /* + * Drop the link from dp to ip, and if ip was a directory, remove the + * '.' and '..' references since we freed the directory. + */ + xfs_dir_update_hook(dp, ip, -1, name); + + /* * If this is a synchronous mount, make sure that the * remove transaction goes to disk before returning to * the user. @@ -2752,6 +2840,20 @@ xfs_cross_rename( } xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE); + + /* + * Inform our hook clients that we've finished an exchange operation as + * follows: removed the source and target files from their directories; + * added the target to the source directory; and added the source to + * the target directory. All inodes are locked, so it's ok to model a + * rename this way so long as we say we deleted entries before we add + * new ones. + */ + xfs_dir_update_hook(dp1, ip1, -1, name1); + xfs_dir_update_hook(dp2, ip2, -1, name2); + xfs_dir_update_hook(dp1, ip2, 1, name1); + xfs_dir_update_hook(dp2, ip1, 1, name2); + return xfs_finish_rename(tp); out_trans_abort: @@ -3135,6 +3237,21 @@ retry: if (new_parent) xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE); + /* + * Inform our hook clients that we've finished a rename operation as + * follows: removed the source and target files from their directories; + * that we've added the source to the target directory; and finally + * that we've added the whiteout, if there was one. All inodes are + * locked, so it's ok to model a rename this way so long as we say we + * deleted entries before we add new ones. + */ + if (target_ip) + xfs_dir_update_hook(target_dp, target_ip, -1, target_name); + xfs_dir_update_hook(src_dp, src_ip, -1, src_name); + xfs_dir_update_hook(target_dp, src_ip, 1, target_name); + if (wip) + xfs_dir_update_hook(src_dp, wip, 1, src_name); + error = xfs_finish_rename(tp); if (wip) xfs_irele(wip); |