Switch to the new kmem_cache_create_rcu() helper which allows us to use
a custom free pointer offset avoiding the need to have an external free
pointer which would grow struct file behind our backs.
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
fs/file_table.c | 6 +++---
include/linux/fs.h | 2 ++
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/fs/file_table.c b/fs/file_table.c
index 694199a1a966..83d5ac1fadc0 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -514,9 +514,9 @@ EXPORT_SYMBOL(__fput_sync);
void __init files_init(void)
{
- filp_cachep = kmem_cache_create("filp", sizeof(struct file), 0,
- SLAB_TYPESAFE_BY_RCU | SLAB_HWCACHE_ALIGN |
- SLAB_PANIC | SLAB_ACCOUNT, NULL);
+ filp_cachep = kmem_cache_create_rcu("filp", sizeof(struct file),
+ offsetof(struct file, f_freeptr),
+ SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT);
percpu_counter_init(&nr_files, 0, GFP_KERNEL);
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 61097a9cf317..5ca83e87adef 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1026,6 +1026,7 @@ static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
* @f_task_work: task work entry point
* @f_llist: work queue entrypoint
* @f_ra: file's readahead state
+ * @f_freeptr: Pointer used by SLAB_TYPESAFE_BY_RCU file cache (don't touch.)
*/
struct file {
atomic_long_t f_count;
@@ -1057,6 +1058,7 @@ struct file {
struct callback_head f_task_work;
struct llist_node f_llist;
struct file_ra_state f_ra;
+ freeptr_t f_freeptr;
};
/* --- cacheline 3 boundary (192 bytes) --- */
} __randomize_layout
--
2.45.2
