UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

io_uring: add basic fixed file allocator 

Applications currently always pick where they want fixed files to go.
In preparation for allowing these types of commands with multishot
support, add a basic allocator in the fixed file table.

Reviewed-by: Hao Xu <howeyxu@tencent.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2022-05-07 14:20:40 -06:00
parent d78bd8adfc
commit b70b8e3331
1 changed files with 29 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
fs/io_uring.c
View File

@ -258,6 +258,7 @@ struct io_rsrc_put {
struct io_file_table {
struct io_fixed_file *files;
unsigned long *bitmap;
unsigned int alloc_hint;
};
struct io_rsrc_node {
@ -4696,6 +4697,31 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return __io_openat_prep(req, sqe);
}
static int __maybe_unused io_file_bitmap_get(struct io_ring_ctx *ctx)
{
struct io_file_table *table = &ctx->file_table;
unsigned long nr = ctx->nr_user_files;
int ret;
if (table->alloc_hint >= nr)
table->alloc_hint = 0;
do {
ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint);
if (ret != nr) {
table->alloc_hint = ret + 1;
return ret;
}
if (!table->alloc_hint)
break;
nr = table->alloc_hint;
table->alloc_hint = 0;
} while (1);
return -ENFILE;
}
static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
{
struct open_flags op;
@ -8664,11 +8690,14 @@ static inline void io_file_bitmap_set(struct io_file_table *table, int bit)
{
WARN_ON_ONCE(test_bit(bit, table->bitmap));
__set_bit(bit, table->bitmap);
if (bit == table->alloc_hint)
table->alloc_hint++;
}
static inline void io_file_bitmap_clear(struct io_file_table *table, int bit)
{
__clear_bit(bit, table->bitmap);
table->alloc_hint = bit;
}
static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)