fsnotify: generalize iteration of marks by object type

Make some code that handles marks of object types inode and vfsmount
generic, so it can handle other object types.

Introduce fsnotify_foreach_obj_type macro to iterate marks by object type
and fsnotify_iter_{should|set}_report_type macros to set/test report_mask.

This is going to be used for adding mark of another object type
(super block mark).

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Amir Goldstein 2018-04-20 16:10:52 -07:00 committed by Jan Kara
parent d9a6f30bb8
commit 47d9c7cc45
4 changed files with 72 additions and 39 deletions

View File

@ -269,25 +269,29 @@ static struct fsnotify_mark *fsnotify_next_mark(struct fsnotify_mark *mark)
static unsigned int fsnotify_iter_select_report_types(
struct fsnotify_iter_info *iter_info)
{
struct fsnotify_mark *inode_mark = iter_info->inode_mark;
struct fsnotify_mark *vfsmount_mark = iter_info->vfsmount_mark;
int cmp;
struct fsnotify_group *max_prio_group = NULL;
struct fsnotify_mark *mark;
int type;
if (!inode_mark && !vfsmount_mark)
return 0;
if (inode_mark && vfsmount_mark) {
cmp = fsnotify_compare_groups(inode_mark->group,
vfsmount_mark->group);
} else {
cmp = inode_mark ? -1 : 1;
/* Choose max prio group among groups of all queue heads */
fsnotify_foreach_obj_type(type) {
mark = iter_info->marks[type];
if (mark &&
fsnotify_compare_groups(max_prio_group, mark->group) > 0)
max_prio_group = mark->group;
}
if (!max_prio_group)
return 0;
/* Set the report mask for marks from same group as max prio group */
iter_info->report_mask = 0;
if (cmp <= 0)
iter_info->report_mask |= FSNOTIFY_OBJ_TYPE_INODE_FL;
if (cmp >= 0)
iter_info->report_mask |= FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL;
fsnotify_foreach_obj_type(type) {
mark = iter_info->marks[type];
if (mark &&
fsnotify_compare_groups(max_prio_group, mark->group) == 0)
fsnotify_iter_set_report_type(iter_info, type);
}
return iter_info->report_mask;
}
@ -298,13 +302,13 @@ static unsigned int fsnotify_iter_select_report_types(
*/
static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)
{
if (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_INODE_FL)
iter_info->inode_mark =
fsnotify_next_mark(iter_info->inode_mark);
int type;
if (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL)
iter_info->vfsmount_mark =
fsnotify_next_mark(iter_info->vfsmount_mark);
fsnotify_foreach_obj_type(type) {
if (fsnotify_iter_should_report_type(iter_info, type))
iter_info->marks[type] =
fsnotify_next_mark(iter_info->marks[type]);
}
}
/*
@ -351,15 +355,15 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
if ((mask & FS_MODIFY) ||
(test_mask & to_tell->i_fsnotify_mask)) {
iter_info.inode_mark =
iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] =
fsnotify_first_mark(&to_tell->i_fsnotify_marks);
}
if (mnt && ((mask & FS_MODIFY) ||
(test_mask & mnt->mnt_fsnotify_mask))) {
iter_info.inode_mark =
iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] =
fsnotify_first_mark(&to_tell->i_fsnotify_marks);
iter_info.vfsmount_mark =
iter_info.marks[FSNOTIFY_OBJ_TYPE_VFSMOUNT] =
fsnotify_first_mark(&mnt->mnt_fsnotify_marks);
}

View File

@ -485,10 +485,10 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
struct fsnotify_group *group)
{
struct inotify_inode_mark *i_mark;
struct fsnotify_iter_info iter_info = {
.inode_mark = fsn_mark,
.report_mask = FSNOTIFY_OBJ_TYPE_INODE_FL,
};
struct fsnotify_iter_info iter_info = { };
fsnotify_iter_set_report_type_mark(&iter_info, FSNOTIFY_OBJ_TYPE_INODE,
fsn_mark);
/* Queue ignore event for the watch */
inotify_handle_event(group, NULL, FS_IN_IGNORED, NULL,

View File

@ -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:
for (type--; type >= 0; type--)
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]);
}
/*

View File

@ -211,23 +211,45 @@ enum fsnotify_obj_type {
#define FSNOTIFY_OBJ_ALL_TYPES_MASK ((1U << FSNOTIFY_OBJ_TYPE_COUNT) - 1)
struct fsnotify_iter_info {
struct fsnotify_mark *inode_mark;
struct fsnotify_mark *vfsmount_mark;
struct fsnotify_mark *marks[FSNOTIFY_OBJ_TYPE_COUNT];
unsigned int report_mask;
int srcu_idx;
};
static inline bool fsnotify_iter_should_report_type(
struct fsnotify_iter_info *iter_info, int type)
{
return (iter_info->report_mask & (1U << type));
}
static inline void fsnotify_iter_set_report_type(
struct fsnotify_iter_info *iter_info, int type)
{
iter_info->report_mask |= (1U << type);
}
static inline void fsnotify_iter_set_report_type_mark(
struct fsnotify_iter_info *iter_info, int type,
struct fsnotify_mark *mark)
{
iter_info->marks[type] = mark;
iter_info->report_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->report_mask & FSNOTIFY_OBJ_TYPE_##NAME##_FL) ? \
iter_info->name##_mark : NULL; \
iter_info->marks[FSNOTIFY_OBJ_TYPE_##NAME] : NULL; \
}
FSNOTIFY_ITER_FUNCS(inode, INODE)
FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT)
#define fsnotify_foreach_obj_type(type) \
for (type = 0; type < FSNOTIFY_OBJ_TYPE_COUNT; 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