io_uring: add helpers for 2 level table alloc
Some parts like fixed file table use 2 level tables, factor out helpers
for allocating/deallocating them as more users are to come.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1709212359cd82eb416d395f86fc78431ccfc0aa.1623634181.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 55e449d..0fbf194 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7059,14 +7059,36 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
}
-static void io_free_file_tables(struct io_file_table *table, unsigned nr_files)
+static void io_free_page_table(void **table, size_t size)
{
- unsigned i, nr_tables = DIV_ROUND_UP(nr_files, IORING_MAX_FILES_TABLE);
+ unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
for (i = 0; i < nr_tables; i++)
- kfree(table->files[i]);
- kfree(table->files);
- table->files = NULL;
+ kfree(table[i]);
+ kfree(table);
+}
+
+static void **io_alloc_page_table(size_t size)
+{
+ unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
+ size_t init_size = size;
+ void **table;
+
+ table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL);
+ if (!table)
+ return NULL;
+
+ for (i = 0; i < nr_tables; i++) {
+ unsigned int this_size = min(size, PAGE_SIZE);
+
+ table[i] = kzalloc(this_size, GFP_KERNEL);
+ if (!table[i]) {
+ io_free_page_table(table, init_size);
+ return NULL;
+ }
+ size -= this_size;
+ }
+ return table;
}
static inline void io_rsrc_ref_lock(struct io_ring_ctx *ctx)
@@ -7195,6 +7217,22 @@ static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
return 0;
}
+static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
+{
+ size_t size = nr_files * sizeof(struct io_fixed_file);
+
+ table->files = (struct io_fixed_file **)io_alloc_page_table(size);
+ return !!table->files;
+}
+
+static void io_free_file_tables(struct io_file_table *table, unsigned nr_files)
+{
+ size_t size = nr_files * sizeof(struct io_fixed_file);
+
+ io_free_page_table((void **)table->files, size);
+ table->files = NULL;
+}
+
static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
{
#if defined(CONFIG_UNIX)
@@ -7456,31 +7494,6 @@ static int io_sqe_files_scm(struct io_ring_ctx *ctx)
}
#endif
-static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
-{
- unsigned i, nr_tables = DIV_ROUND_UP(nr_files, IORING_MAX_FILES_TABLE);
-
- table->files = kcalloc(nr_tables, sizeof(*table->files), GFP_KERNEL);
- if (!table->files)
- return false;
-
- for (i = 0; i < nr_tables; i++) {
- unsigned int this_files = min(nr_files, IORING_MAX_FILES_TABLE);
-
- table->files[i] = kcalloc(this_files, sizeof(*table->files[i]),
- GFP_KERNEL);
- if (!table->files[i])
- break;
- nr_files -= this_files;
- }
-
- if (i == nr_tables)
- return true;
-
- io_free_file_tables(table, nr_tables * IORING_MAX_FILES_TABLE);
- return false;
-}
-
static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
{
struct file *file = prsrc->file;
