io_uring: refactor file tables alloc/free

Introduce a heler io_free_file_tables() doing all the cleaning, there
are several places where it's hand coded. Also move all allocations into
io_sqe_alloc_file_tables() and rename it, so all of it is in one place.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/502a84ebf41ff119b095e59661e678eacb752bf8.1617287883.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 4700de3..663e1cf 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7054,6 +7054,16 @@ 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_rsrc_data *data, unsigned nr_files)
+{
+       unsigned i, nr_tables = DIV_ROUND_UP(nr_files, IORING_MAX_FILES_TABLE);
+
+       for (i = 0; i < nr_tables; i++)
+               kfree(data->table[i].files);
+       kfree(data->table);
+       data->table = NULL;
+}
+
 static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
 {
 #if defined(CONFIG_UNIX)
@@ -7190,14 +7200,12 @@ static struct io_rsrc_data *io_rsrc_data_alloc(struct io_ring_ctx *ctx,
 static void io_rsrc_data_free(struct io_rsrc_data *data)
 {
        percpu_ref_exit(&data->refs);
-       kfree(data->table);
        kfree(data);
 }
 
 static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
 {
        struct io_rsrc_data *data = ctx->file_data;
-       unsigned nr_tables, i;
        int ret;
 
        if (!data)
@@ -7207,9 +7215,7 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
                return ret;
 
        __io_sqe_files_unregister(ctx);
-       nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE);
-       for (i = 0; i < nr_tables; i++)
-               kfree(data->table[i].files);
+       io_free_file_tables(data, ctx->nr_user_files);
        io_rsrc_data_free(data);
        ctx->file_data = NULL;
        ctx->nr_user_files = 0;
@@ -7439,16 +7445,20 @@ static int io_sqe_files_scm(struct io_ring_ctx *ctx)
 }
 #endif
 
-static int io_sqe_alloc_file_tables(struct io_rsrc_data *file_data,
-                                   unsigned nr_tables, unsigned nr_files)
+static bool io_alloc_file_tables(struct io_rsrc_data *file_data,
+                                unsigned nr_files)
 {
-       int i;
+       unsigned i, nr_tables = DIV_ROUND_UP(nr_files, IORING_MAX_FILES_TABLE);
+
+       file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
+                                  GFP_KERNEL);
+       if (!file_data->table)
+               return false;
 
        for (i = 0; i < nr_tables; i++) {
                struct fixed_rsrc_table *table = &file_data->table[i];
-               unsigned this_files;
+               unsigned int this_files = min(nr_files, IORING_MAX_FILES_TABLE);
 
-               this_files = min(nr_files, IORING_MAX_FILES_TABLE);
                table->files = kcalloc(this_files, sizeof(struct file *),
                                        GFP_KERNEL);
                if (!table->files)
@@ -7457,13 +7467,10 @@ static int io_sqe_alloc_file_tables(struct io_rsrc_data *file_data,
        }
 
        if (i == nr_tables)
-               return 0;
+               return true;
 
-       for (i = 0; i < nr_tables; i++) {
-               struct fixed_rsrc_table *table = &file_data->table[i];
-               kfree(table->files);
-       }
-       return 1;
+       io_free_file_tables(file_data, nr_tables * IORING_MAX_FILES_TABLE);
+       return false;
 }
 
 static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
@@ -7613,9 +7620,9 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
                                 unsigned nr_args)
 {
        __s32 __user *fds = (__s32 __user *) arg;
-       unsigned nr_tables, i;
        struct file *file;
        int fd, ret;
+       unsigned i;
        struct io_rsrc_data *file_data;
 
        if (ctx->file_data)
@@ -7634,13 +7641,7 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
        ctx->file_data = file_data;
 
        ret = -ENOMEM;
-       nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);
-       file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
-                                  GFP_KERNEL);
-       if (!file_data->table)
-               goto out_free;
-
-       if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))
+       if (!io_alloc_file_tables(file_data, nr_args))
                goto out_free;
 
        for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
@@ -7685,8 +7686,7 @@ out_fput:
                if (file)
                        fput(file);
        }
-       for (i = 0; i < nr_tables; i++)
-               kfree(file_data->table[i].files);
+       io_free_file_tables(file_data, nr_args);
        ctx->nr_user_files = 0;
 out_free:
        io_rsrc_data_free(ctx->file_data);