From d6f7b98bc8147abd290ead82922f8d83c525fb42 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Fri, 20 Apr 2018 16:10:49 -0700 Subject: [PATCH] fsnotify: use type id to identify connector object type An fsnotify_mark_connector is referencing a single type of object (either inode or vfsmount). Instead of storing a type mask in connector->flags, store a single type id in connector->type to identify the type of object. When a connector object is detached from the object, its type is set to FSNOTIFY_OBJ_TYPE_DETACHED and this object is not going to be reused. The function fsnotify_clear_marks_by_group() is the only place where type mask was used, so use type flags instead of type id to this function. This change is going to be more convenient when adding a new object type (super block). Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara --- fs/notify/fdinfo.c | 6 +++--- fs/notify/group.c | 2 +- fs/notify/mark.c | 29 ++++++++++++++--------------- include/linux/fsnotify_backend.h | 21 ++++++++++++++------- 4 files changed, 32 insertions(+), 26 deletions(-) diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c index d478629c728b..10aac1942c9f 100644 --- a/fs/notify/fdinfo.c +++ b/fs/notify/fdinfo.c @@ -77,7 +77,7 @@ static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark) struct inotify_inode_mark *inode_mark; struct inode *inode; - if (!(mark->connector->flags & FSNOTIFY_OBJ_TYPE_INODE)) + if (mark->connector->type != FSNOTIFY_OBJ_TYPE_INODE) return; inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark); @@ -116,7 +116,7 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark) if (mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY) mflags |= FAN_MARK_IGNORED_SURV_MODIFY; - if (mark->connector->flags & FSNOTIFY_OBJ_TYPE_INODE) { + if (mark->connector->type == FSNOTIFY_OBJ_TYPE_INODE) { inode = igrab(mark->connector->inode); if (!inode) return; @@ -126,7 +126,7 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark) show_mark_fhandle(m, inode); seq_putc(m, '\n'); iput(inode); - } else if (mark->connector->flags & FSNOTIFY_OBJ_TYPE_VFSMOUNT) { + } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) { struct mount *mnt = real_mount(mark->connector->mnt); seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n", diff --git a/fs/notify/group.c b/fs/notify/group.c index b7a4b6a69efa..aa5468f23e45 100644 --- a/fs/notify/group.c +++ b/fs/notify/group.c @@ -67,7 +67,7 @@ void fsnotify_destroy_group(struct fsnotify_group *group) fsnotify_group_stop_queueing(group); /* Clear all marks for this group and queue them for destruction */ - fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_ALL_TYPES); + fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_ALL_TYPES_MASK); /* * Some marks can still be pinned when waiting for response from diff --git a/fs/notify/mark.c b/fs/notify/mark.c index e9191b416434..ef44808b28ca 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -119,9 +119,9 @@ static void __fsnotify_recalc_mask(struct fsnotify_mark_connector *conn) if (mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED) new_mask |= mark->mask; } - if (conn->flags & FSNOTIFY_OBJ_TYPE_INODE) + if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) conn->inode->i_fsnotify_mask = new_mask; - else if (conn->flags & FSNOTIFY_OBJ_TYPE_VFSMOUNT) + else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) real_mount(conn->mnt)->mnt_fsnotify_mask = new_mask; } @@ -139,7 +139,7 @@ void fsnotify_recalc_mask(struct fsnotify_mark_connector *conn) spin_lock(&conn->lock); __fsnotify_recalc_mask(conn); spin_unlock(&conn->lock); - if (conn->flags & FSNOTIFY_OBJ_TYPE_INODE) + if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) __fsnotify_update_child_dentry_flags(conn->inode); } @@ -166,18 +166,18 @@ static struct inode *fsnotify_detach_connector_from_object( { struct inode *inode = NULL; - if (conn->flags & FSNOTIFY_OBJ_TYPE_INODE) { + if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) { inode = conn->inode; rcu_assign_pointer(inode->i_fsnotify_marks, NULL); inode->i_fsnotify_mask = 0; conn->inode = NULL; - conn->flags &= ~FSNOTIFY_OBJ_TYPE_INODE; - } else if (conn->flags & FSNOTIFY_OBJ_TYPE_VFSMOUNT) { + conn->type = FSNOTIFY_OBJ_TYPE_DETACHED; + } else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) { rcu_assign_pointer(real_mount(conn->mnt)->mnt_fsnotify_marks, NULL); real_mount(conn->mnt)->mnt_fsnotify_mask = 0; conn->mnt = NULL; - conn->flags &= ~FSNOTIFY_OBJ_TYPE_VFSMOUNT; + conn->type = FSNOTIFY_OBJ_TYPE_DETACHED; } return inode; @@ -442,10 +442,10 @@ static int fsnotify_attach_connector_to_object( spin_lock_init(&conn->lock); INIT_HLIST_HEAD(&conn->list); if (inode) { - conn->flags = FSNOTIFY_OBJ_TYPE_INODE; + conn->type = FSNOTIFY_OBJ_TYPE_INODE; conn->inode = igrab(inode); } else { - conn->flags = FSNOTIFY_OBJ_TYPE_VFSMOUNT; + conn->type = FSNOTIFY_OBJ_TYPE_VFSMOUNT; conn->mnt = mnt; } /* @@ -479,8 +479,7 @@ static struct fsnotify_mark_connector *fsnotify_grab_connector( if (!conn) goto out; spin_lock(&conn->lock); - if (!(conn->flags & (FSNOTIFY_OBJ_TYPE_INODE | - FSNOTIFY_OBJ_TYPE_VFSMOUNT))) { + if (conn->type == FSNOTIFY_OBJ_TYPE_DETACHED) { spin_unlock(&conn->lock); srcu_read_unlock(&fsnotify_mark_srcu, idx); return NULL; @@ -646,16 +645,16 @@ struct fsnotify_mark *fsnotify_find_mark( return NULL; } -/* Clear any marks in a group with given type */ +/* Clear any marks in a group with given type mask */ void fsnotify_clear_marks_by_group(struct fsnotify_group *group, - unsigned int type) + unsigned int type_mask) { struct fsnotify_mark *lmark, *mark; LIST_HEAD(to_free); struct list_head *head = &to_free; /* Skip selection step if we want to clear all marks. */ - if (type == FSNOTIFY_OBJ_ALL_TYPES) { + if (type_mask == FSNOTIFY_OBJ_ALL_TYPES_MASK) { head = &group->marks_list; goto clear; } @@ -670,7 +669,7 @@ void fsnotify_clear_marks_by_group(struct fsnotify_group *group, */ mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING); list_for_each_entry_safe(mark, lmark, &group->marks_list, g_list) { - if (mark->connector->flags & type) + if ((1U << mark->connector->type) & type_mask) list_move(&mark->g_list, &to_free); } mutex_unlock(&group->mark_mutex); diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index e64c0294f50b..435c94a31c8c 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -201,6 +201,17 @@ struct fsnotify_group { #define FSNOTIFY_EVENT_PATH 1 #define FSNOTIFY_EVENT_INODE 2 +enum fsnotify_obj_type { + FSNOTIFY_OBJ_TYPE_INODE, + FSNOTIFY_OBJ_TYPE_VFSMOUNT, + FSNOTIFY_OBJ_TYPE_COUNT, + FSNOTIFY_OBJ_TYPE_DETACHED = FSNOTIFY_OBJ_TYPE_COUNT +}; + +#define FSNOTIFY_OBJ_TYPE_INODE_FL (1U << FSNOTIFY_OBJ_TYPE_INODE) +#define FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL (1U << FSNOTIFY_OBJ_TYPE_VFSMOUNT) +#define FSNOTIFY_OBJ_ALL_TYPES_MASK ((1U << FSNOTIFY_OBJ_TYPE_COUNT) - 1) + /* * Inode / vfsmount point to this structure which tracks all marks attached to * the inode / vfsmount. The reference to inode / vfsmount is held by this @@ -209,11 +220,7 @@ struct fsnotify_group { */ struct fsnotify_mark_connector { spinlock_t lock; -#define FSNOTIFY_OBJ_TYPE_INODE 0x01 -#define FSNOTIFY_OBJ_TYPE_VFSMOUNT 0x02 -#define FSNOTIFY_OBJ_ALL_TYPES (FSNOTIFY_OBJ_TYPE_INODE | \ - FSNOTIFY_OBJ_TYPE_VFSMOUNT) - unsigned int flags; /* Type of object [lock] */ + unsigned int type; /* Type of object [lock] */ union { /* Object pointer [lock] */ struct inode *inode; struct vfsmount *mnt; @@ -369,12 +376,12 @@ extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group, unsigned /* run all the marks in a group, and clear all of the vfsmount marks */ static inline void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group) { - fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_VFSMOUNT); + fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL); } /* run all the marks in a group, and clear all of the inode marks */ static inline void fsnotify_clear_inode_marks_by_group(struct fsnotify_group *group) { - fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_INODE); + fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_INODE_FL); } extern void fsnotify_get_mark(struct fsnotify_mark *mark); extern void fsnotify_put_mark(struct fsnotify_mark *mark); -- 2.25.1