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Message-Id: <20210629191035.681913-5-krisman@collabora.com>
Date: Tue, 29 Jun 2021 15:10:24 -0400
From: Gabriel Krisman Bertazi <krisman@...labora.com>
To: amir73il@...il.com
Cc: djwong@...nel.org, tytso@....edu, david@...morbit.com,
jack@...e.com, dhowells@...hat.com, khazhy@...gle.com,
linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
Gabriel Krisman Bertazi <krisman@...labora.com>,
kernel@...labora.com
Subject: [PATCH v3 04/15] fanotify: Split superblock marks out to a new cache
FAN_ERROR will require an error structure to be stored per mark. But,
since FAN_ERROR doesn't apply to inode/mount marks, it should suffice to
only expose this information for superblock marks. Therefore, wrap this
kind of marks into a container and plumb it for the future.
Signed-off-by: Gabriel Krisman Bertazi <krisman@...labora.com>
---
Changes since v2:
- Move mark initialization to fanotify_alloc_mark (Amir)
Changes since v1:
- Only extend superblock marks (Amir)
---
fs/notify/fanotify/fanotify.c | 10 ++++++--
fs/notify/fanotify/fanotify.h | 13 ++++++++++
fs/notify/fanotify/fanotify_user.c | 38 ++++++++++++++++++++++++++++--
include/linux/fsnotify_backend.h | 1 +
4 files changed, 58 insertions(+), 4 deletions(-)
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 310246f8d3f1..0f760770d4c9 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -869,9 +869,15 @@ static void fanotify_freeing_mark(struct fsnotify_mark *mark,
dec_ucount(group->fanotify_data.ucounts, UCOUNT_FANOTIFY_MARKS);
}
-static void fanotify_free_mark(struct fsnotify_mark *fsn_mark)
+static void fanotify_free_mark(struct fsnotify_mark *mark)
{
- kmem_cache_free(fanotify_mark_cache, fsn_mark);
+ if (mark->flags & FSNOTIFY_MARK_FLAG_SB) {
+ struct fanotify_sb_mark *fa_mark = FANOTIFY_SB_MARK(mark);
+
+ kmem_cache_free(fanotify_sb_mark_cache, fa_mark);
+ } else {
+ kmem_cache_free(fanotify_mark_cache, mark);
+ }
}
const struct fsnotify_ops fanotify_fsnotify_ops = {
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index 4a5e555dc3d2..fd125a949187 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -6,6 +6,7 @@
#include <linux/hashtable.h>
extern struct kmem_cache *fanotify_mark_cache;
+extern struct kmem_cache *fanotify_sb_mark_cache;
extern struct kmem_cache *fanotify_fid_event_cachep;
extern struct kmem_cache *fanotify_path_event_cachep;
extern struct kmem_cache *fanotify_perm_event_cachep;
@@ -129,6 +130,18 @@ static inline void fanotify_info_copy_name(struct fanotify_info *info,
name->name);
}
+struct fanotify_sb_mark {
+ struct fsnotify_mark fsn_mark;
+};
+
+static inline
+struct fanotify_sb_mark *FANOTIFY_SB_MARK(struct fsnotify_mark *mark)
+{
+ WARN_ON(!(mark->flags & FSNOTIFY_MARK_FLAG_SB));
+
+ return container_of(mark, struct fanotify_sb_mark, fsn_mark);
+}
+
/*
* Common structure for fanotify events. Concrete structs are allocated in
* fanotify_handle_event() and freed when the information is retrieved by
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 67b18dfe0025..a42521e140e6 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -99,6 +99,7 @@ struct ctl_table fanotify_table[] = {
extern const struct fsnotify_ops fanotify_fsnotify_ops;
struct kmem_cache *fanotify_mark_cache __read_mostly;
+struct kmem_cache *fanotify_sb_mark_cache __read_mostly;
struct kmem_cache *fanotify_fid_event_cachep __read_mostly;
struct kmem_cache *fanotify_path_event_cachep __read_mostly;
struct kmem_cache *fanotify_perm_event_cachep __read_mostly;
@@ -915,6 +916,38 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
return mask & ~oldmask;
}
+static struct fsnotify_mark *fanotify_alloc_mark(struct fsnotify_group *group,
+ unsigned int type)
+{
+ struct fanotify_sb_mark *sb_mark;
+ struct fsnotify_mark *mark;
+
+ switch (type) {
+ case FSNOTIFY_OBJ_TYPE_SB:
+ sb_mark = kmem_cache_zalloc(fanotify_sb_mark_cache, GFP_KERNEL);
+ if (!sb_mark)
+ return NULL;
+ mark = &sb_mark->fsn_mark;
+ break;
+
+ case FSNOTIFY_OBJ_TYPE_INODE:
+ case FSNOTIFY_OBJ_TYPE_PARENT:
+ case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
+ mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
+ break;
+ default:
+ WARN_ON(1);
+ return NULL;
+ }
+
+ fsnotify_init_mark(mark, group);
+
+ if (type == FSNOTIFY_OBJ_TYPE_SB)
+ mark->flags |= FSNOTIFY_MARK_FLAG_SB;
+
+ return mark;
+}
+
static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
fsnotify_connp_t *connp,
unsigned int type,
@@ -933,13 +966,12 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
!inc_ucount(ucounts->ns, ucounts->uid, UCOUNT_FANOTIFY_MARKS))
return ERR_PTR(-ENOSPC);
- mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
+ mark = fanotify_alloc_mark(group, type);
if (!mark) {
ret = -ENOMEM;
goto out_dec_ucounts;
}
- fsnotify_init_mark(mark, group);
ret = fsnotify_add_mark_locked(mark, connp, type, 0, fsid);
if (ret) {
fsnotify_put_mark(mark);
@@ -1497,6 +1529,8 @@ static int __init fanotify_user_setup(void)
fanotify_mark_cache = KMEM_CACHE(fsnotify_mark,
SLAB_PANIC|SLAB_ACCOUNT);
+ fanotify_sb_mark_cache = KMEM_CACHE(fanotify_sb_mark,
+ SLAB_PANIC|SLAB_ACCOUNT);
fanotify_fid_event_cachep = KMEM_CACHE(fanotify_fid_event,
SLAB_PANIC);
fanotify_path_event_cachep = KMEM_CACHE(fanotify_path_event,
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 1ce66748a2d2..c4473b467c28 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -401,6 +401,7 @@ struct fsnotify_mark {
#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x01
#define FSNOTIFY_MARK_FLAG_ALIVE 0x02
#define FSNOTIFY_MARK_FLAG_ATTACHED 0x04
+#define FSNOTIFY_MARK_FLAG_SB 0x08
unsigned int flags; /* flags [mark->lock] */
};
--
2.32.0
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