Make some code that handles marks of object types inode and vfsmount
generic, so it can handle other object types.
Introduce foreach_obj_type macros to iterate marks by object type
with or without consulting a type mask.
This is going to be used for adding mark of another object type
(super block mark).
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
---
fs/notify/fsnotify.c | 54 ++++++++++++++++++++++++----------------
fs/notify/mark.c | 23 +++++++++++------
include/linux/fsnotify_backend.h | 38 +++++++++++++++++++++-------
3 files changed, 76 insertions(+), 39 deletions(-)
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 665f681dd913..1759121db50d 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -263,21 +263,31 @@ static struct fsnotify_mark *fsnotify_next_mark(struct fsnotify_mark *mark)
/*
* iter_info is a multi head priority queue of marks.
* fsnotify_iter_first() picks a subset of marks from queue heads, all with the
- * same priority and clears the type_mask for other marks.
+ * same group and clears the type_mask for other marks.
* Returns the type_mask of the chosen subset.
*/
static unsigned int fsnotify_iter_first(struct fsnotify_iter_info *iter_info)
{
- struct fsnotify_mark *inode_mark = iter_info->inode_mark;
- struct fsnotify_mark *vfsmount_mark = iter_info->vfsmount_mark;
-
- if (inode_mark && vfsmount_mark) {
- int cmp = fsnotify_compare_groups(inode_mark->group,
- vfsmount_mark->group);
- if (cmp > 0)
- iter_info->type_mask &= ~FSNOTIFY_OBJ_TYPE_INODE_FL;
- else if (cmp < 0)
- iter_info->type_mask &= ~FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL;
+ struct fsnotify_group *max_prio_group = NULL;
+ unsigned int type_mask = iter_info->type_mask;
+ struct fsnotify_mark *mark;
+ int type;
+
+ if (!type_mask || is_power_of_2(type_mask))
+ return type_mask;
+
+ /* Choose max prio group among groups of all queue heads */
+ fsnotify_iter_foreach_obj_type_mark(iter_info, type, mark) {
+ if (mark &&
+ fsnotify_compare_groups(max_prio_group, mark->group) > 0)
+ max_prio_group = mark->group;
+ }
+
+ /* Clear the type mask for marks with other groups */
+ fsnotify_iter_foreach_obj_type_mark(iter_info, type, mark) {
+ if (mark &&
+ fsnotify_compare_groups(max_prio_group, mark->group) != 0)
+ iter_info->type_mask &= ~(1U << type);
}
return iter_info->type_mask;
@@ -289,17 +299,17 @@ static unsigned int fsnotify_iter_first(struct fsnotify_iter_info *iter_info)
*/
static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)
{
- if (iter_info->type_mask & FSNOTIFY_OBJ_TYPE_INODE_FL)
- fsnotify_iter_set_inode_mark(iter_info,
- fsnotify_next_mark(iter_info->inode_mark));
- else if (iter_info->inode_mark)
- iter_info->type_mask |= FSNOTIFY_OBJ_TYPE_INODE_FL;
-
- if (iter_info->type_mask & FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL)
- fsnotify_iter_set_vfsmount_mark(iter_info,
- fsnotify_next_mark(iter_info->vfsmount_mark));
- else if (iter_info->vfsmount_mark)
- iter_info->type_mask |= FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL;
+ int type;
+
+ fsnotify_foreach_obj_type(type) {
+ unsigned int flag = 1U << type;
+
+ if (iter_info->type_mask & flag)
+ fsnotify_iter_set_type_mark(iter_info, type,
+ fsnotify_next_mark(iter_info->marks[type]));
+ else if (iter_info->marks[type])
+ iter_info->type_mask |= flag;
+ }
}
/*
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index ef44808b28ca..3df2d5ecf0b7 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -294,12 +294,12 @@ static void fsnotify_put_mark_wake(struct fsnotify_mark *mark)
bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info)
{
- /* This can fail if mark is being removed */
- if (!fsnotify_get_mark_safe(iter_info->inode_mark))
- return false;
- if (!fsnotify_get_mark_safe(iter_info->vfsmount_mark)) {
- fsnotify_put_mark_wake(iter_info->inode_mark);
- return false;
+ int type;
+
+ fsnotify_foreach_obj_type(type) {
+ /* This can fail if mark is being removed */
+ if (!fsnotify_get_mark_safe(iter_info->marks[type]))
+ goto fail;
}
/*
@@ -310,13 +310,20 @@ bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info)
srcu_read_unlock(&fsnotify_mark_srcu, iter_info->srcu_idx);
return true;
+
+fail:
+ while (type-- > 0)
+ fsnotify_put_mark_wake(iter_info->marks[type]);
+ return false;
}
void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info)
{
+ int type;
+
iter_info->srcu_idx = srcu_read_lock(&fsnotify_mark_srcu);
- fsnotify_put_mark_wake(iter_info->inode_mark);
- fsnotify_put_mark_wake(iter_info->vfsmount_mark);
+ fsnotify_foreach_obj_type(type)
+ fsnotify_put_mark_wake(iter_info->marks[type]);
}
/*
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 62e05b8a9bc7..2f8c4255e679 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -211,34 +211,54 @@ enum fsnotify_obj_type {
#define FSNOTIFY_OBJ_ALL_TYPES_MASK ((1U << FSNOTIFY_OBJ_TYPE_MAX) - 1)
struct fsnotify_iter_info {
- struct fsnotify_mark *inode_mark;
- struct fsnotify_mark *vfsmount_mark;
+ struct fsnotify_mark *marks[FSNOTIFY_OBJ_TYPE_MAX];
unsigned int type_mask;
int srcu_idx;
};
+static inline struct fsnotify_mark *fsnotify_iter_type_mark(
+ struct fsnotify_iter_info *iter_info, int type)
+{
+ return (iter_info->type_mask & (1U << type)) ?
+ iter_info->marks[type] : NULL;
+}
+
+static inline void fsnotify_iter_set_type_mark(
+ struct fsnotify_iter_info *iter_info,
+ int type, struct fsnotify_mark *mark)
+{
+ iter_info->marks[type] = mark;
+ if (mark)
+ iter_info->type_mask |= (1U << type);
+ else
+ iter_info->type_mask &= ~(1U << type);
+}
+
#define FSNOTIFY_ITER_FUNCS(name, NAME) \
static inline struct fsnotify_mark *fsnotify_iter_##name##_mark( \
struct fsnotify_iter_info *iter_info) \
{ \
- return (iter_info->type_mask & FSNOTIFY_OBJ_TYPE_##NAME##_FL) ? \
- iter_info->name##_mark : NULL; \
+ return fsnotify_iter_type_mark(iter_info, FSNOTIFY_OBJ_TYPE_##NAME); \
} \
\
static inline void fsnotify_iter_set_##name##_mark( \
struct fsnotify_iter_info *iter_info, \
struct fsnotify_mark *mark) \
{ \
- iter_info->name##_mark = mark; \
- if (mark) \
- iter_info->type_mask |= FSNOTIFY_OBJ_TYPE_##NAME##_FL; \
- else \
- iter_info->type_mask &= ~FSNOTIFY_OBJ_TYPE_##NAME##_FL; \
+ fsnotify_iter_set_type_mark(iter_info, FSNOTIFY_OBJ_TYPE_##NAME, mark); \
}
FSNOTIFY_ITER_FUNCS(inode, INODE)
FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT)
+#define fsnotify_foreach_obj_type(type) \
+ for (type = 0; type < FSNOTIFY_OBJ_TYPE_MAX; type++)
+
+#define fsnotify_iter_foreach_obj_type_mark(iter, type, mark) \
+ for (type = 0, mark = fsnotify_iter_type_mark(iter, type); \
+ type < FSNOTIFY_OBJ_TYPE_MAX; \
+ type++, mark = fsnotify_iter_type_mark(iter, type)) \
+
/*
* Inode / vfsmount point to this structure which tracks all marks attached to
* the inode / vfsmount. The reference to inode / vfsmount is held by this
--
2.7.4
