From 9e24c7df2b563618adf25b987402f1123e69abab Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Sat, 19 Mar 2022 15:01:31 +0200 Subject: [PATCH] inotify: move control flags from mask to mark flags The inotify control flags in the mark mask (e.g. FS_IN_ONE_SHOT) are not relevant to object interest mask, so move them to the mark flags. This frees up some bits in the object interest mask. Signed-off-by: Amir Goldstein --- fs/notify/fsnotify.c | 4 +-- fs/notify/inotify/inotify.h | 11 ++++++-- fs/notify/inotify/inotify_fsnotify.c | 2 +- fs/notify/inotify/inotify_user.c | 38 ++++++++++++++++++---------- include/linux/fsnotify_backend.h | 15 ++++++----- 5 files changed, 44 insertions(+), 26 deletions(-) diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 70a8516b78bc5..6eee19d15e8cd 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -253,7 +253,7 @@ static int fsnotify_handle_inode_event(struct fsnotify_group *group, if (WARN_ON_ONCE(!inode && !dir)) return 0; - if ((inode_mark->mask & FS_EXCL_UNLINK) && + if ((inode_mark->flags & FSNOTIFY_MARK_FLAG_EXCL_UNLINK) && path && d_unlinked(path->dentry)) return 0; @@ -581,7 +581,7 @@ static __init int fsnotify_init(void) { int ret; - BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 25); + BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 23); ret = init_srcu_struct(&fsnotify_mark_srcu); if (ret) diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h index 8f00151eb731f..7d5df7a215397 100644 --- a/fs/notify/inotify/inotify.h +++ b/fs/notify/inotify/inotify.h @@ -27,11 +27,18 @@ static inline struct inotify_event_info *INOTIFY_E(struct fsnotify_event *fse) * userspace. There is at least one bit (FS_EVENT_ON_CHILD) which is * used only internally to the kernel. */ -#define INOTIFY_USER_MASK (IN_ALL_EVENTS | IN_ONESHOT | IN_EXCL_UNLINK) +#define INOTIFY_USER_MASK (IN_ALL_EVENTS) static inline __u32 inotify_mark_user_mask(struct fsnotify_mark *fsn_mark) { - return fsn_mark->mask & INOTIFY_USER_MASK; + __u32 mask = fsn_mark->mask & INOTIFY_USER_MASK; + + if (fsn_mark->flags & FSNOTIFY_MARK_FLAG_EXCL_UNLINK) + mask |= IN_EXCL_UNLINK; + if (fsn_mark->flags & FSNOTIFY_MARK_FLAG_IN_ONESHOT) + mask |= IN_ONESHOT; + + return mask; } extern void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index d92d7b0adc9a2..49cfe2ae6d23d 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -122,7 +122,7 @@ int inotify_handle_inode_event(struct fsnotify_mark *inode_mark, u32 mask, fsnotify_destroy_event(group, fsn_event); } - if (inode_mark->mask & IN_ONESHOT) + if (inode_mark->flags & FSNOTIFY_MARK_FLAG_IN_ONESHOT) fsnotify_destroy_mark(inode_mark, group); return 0; diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 3ef57db0ec9d6..d8907d32a05b9 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -115,6 +115,21 @@ static inline __u32 inotify_arg_to_mask(struct inode *inode, u32 arg) return mask; } +#define INOTIFY_MARK_FLAGS \ + (FSNOTIFY_MARK_FLAG_EXCL_UNLINK | FSNOTIFY_MARK_FLAG_IN_ONESHOT) + +static inline unsigned int inotify_arg_to_flags(u32 arg) +{ + unsigned int flags = 0; + + if (arg & IN_EXCL_UNLINK) + flags |= FSNOTIFY_MARK_FLAG_EXCL_UNLINK; + if (arg & IN_ONESHOT) + flags |= FSNOTIFY_MARK_FLAG_IN_ONESHOT; + + return flags; +} + static inline u32 inotify_mask_to_arg(__u32 mask) { return mask & (IN_ALL_EVENTS | IN_ISDIR | IN_UNMOUNT | IN_IGNORED | @@ -526,13 +541,10 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, struct fsnotify_mark *fsn_mark; struct inotify_inode_mark *i_mark; __u32 old_mask, new_mask; - __u32 mask; - int add = (arg & IN_MASK_ADD); + int replace = !(arg & IN_MASK_ADD); int create = (arg & IN_MASK_CREATE); int ret; - mask = inotify_arg_to_mask(inode, arg); - fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); if (!fsn_mark) return -ENOENT; @@ -545,10 +557,12 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, spin_lock(&fsn_mark->lock); old_mask = fsn_mark->mask; - if (add) - fsn_mark->mask |= mask; - else - fsn_mark->mask = mask; + if (replace) { + fsn_mark->mask = 0; + fsn_mark->flags &= ~INOTIFY_MARK_FLAGS; + } + fsn_mark->mask |= inotify_arg_to_mask(inode, arg); + fsn_mark->flags |= inotify_arg_to_flags(arg); new_mask = fsn_mark->mask; spin_unlock(&fsn_mark->lock); @@ -579,19 +593,17 @@ static int inotify_new_watch(struct fsnotify_group *group, u32 arg) { struct inotify_inode_mark *tmp_i_mark; - __u32 mask; int ret; struct idr *idr = &group->inotify_data.idr; spinlock_t *idr_lock = &group->inotify_data.idr_lock; - mask = inotify_arg_to_mask(inode, arg); - tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); if (unlikely(!tmp_i_mark)) return -ENOMEM; fsnotify_init_mark(&tmp_i_mark->fsn_mark, group); - tmp_i_mark->fsn_mark.mask = mask; + tmp_i_mark->fsn_mark.mask = inotify_arg_to_mask(inode, arg); + tmp_i_mark->fsn_mark.flags = inotify_arg_to_flags(arg); tmp_i_mark->wd = -1; ret = inotify_add_to_idr(idr, idr_lock, tmp_i_mark); @@ -845,9 +857,7 @@ static int __init inotify_user_setup(void) BUILD_BUG_ON(IN_UNMOUNT != FS_UNMOUNT); BUILD_BUG_ON(IN_Q_OVERFLOW != FS_Q_OVERFLOW); BUILD_BUG_ON(IN_IGNORED != FS_IN_IGNORED); - BUILD_BUG_ON(IN_EXCL_UNLINK != FS_EXCL_UNLINK); BUILD_BUG_ON(IN_ISDIR != FS_ISDIR); - BUILD_BUG_ON(IN_ONESHOT != FS_IN_ONESHOT); BUILD_BUG_ON(HWEIGHT32(ALL_INOTIFY_BITS) != 22); diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 0805b74cae441..8ecdc1750e674 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -55,7 +55,6 @@ #define FS_ACCESS_PERM 0x00020000 /* access event in a permissions hook */ #define FS_OPEN_EXEC_PERM 0x00040000 /* open/exec event in a permission hook */ -#define FS_EXCL_UNLINK 0x04000000 /* do not send events if object is unlinked */ /* * Set on inode mark that cares about things that happen to its children. * Always set for dnotify and inotify. @@ -66,7 +65,6 @@ #define FS_RENAME 0x10000000 /* File was renamed */ #define FS_DN_MULTISHOT 0x20000000 /* dnotify multishot */ #define FS_ISDIR 0x40000000 /* event occurred against dir */ -#define FS_IN_ONESHOT 0x80000000 /* only send event once */ #define FS_MOVE (FS_MOVED_FROM | FS_MOVED_TO) @@ -106,8 +104,7 @@ FS_ERROR) /* Extra flags that may be reported with event or control handling of events */ -#define ALL_FSNOTIFY_FLAGS (FS_EXCL_UNLINK | FS_ISDIR | FS_IN_ONESHOT | \ - FS_DN_MULTISHOT | FS_EVENT_ON_CHILD) +#define ALL_FSNOTIFY_FLAGS (FS_ISDIR | FS_EVENT_ON_CHILD | FS_DN_MULTISHOT) #define ALL_FSNOTIFY_BITS (ALL_FSNOTIFY_EVENTS | ALL_FSNOTIFY_FLAGS) @@ -473,9 +470,13 @@ struct fsnotify_mark { struct fsnotify_mark_connector *connector; /* Events types to ignore [mark->lock, group->mark_mutex] */ __u32 ignored_mask; -#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x01 -#define FSNOTIFY_MARK_FLAG_ALIVE 0x02 -#define FSNOTIFY_MARK_FLAG_ATTACHED 0x04 + /* Internal fsnotify flags */ +#define FSNOTIFY_MARK_FLAG_ALIVE 0x0001 +#define FSNOTIFY_MARK_FLAG_ATTACHED 0x0002 + /* Backend controlled flags */ +#define FSNOTIFY_MARK_FLAG_EXCL_UNLINK 0x0010 +#define FSNOTIFY_MARK_FLAG_IN_ONESHOT 0x0020 +#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x0100 unsigned int flags; /* flags [mark->lock] */ };