diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2020-04-12 01:05:02 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-04-12 16:46:30 +0200 |
| commit | bf9c2f1cdcc718b6d2d41172f6ca005fe22cc7ff (patch) | |
| tree | 3cf6b7cd0f583c4f22afd609e5f2776c0997ee02 /fs | |
| parent | io_uring: remove obsolete @mm_fault (diff) | |
| download | linux-bf9c2f1cdcc718b6d2d41172f6ca005fe22cc7ff.tar.xz linux-bf9c2f1cdcc718b6d2d41172f6ca005fe22cc7ff.zip | |
io_uring: track mm through current->mm
As a preparation for extracting request init bits, remove self-coded mm
tracking from io_submit_sqes(), but rely on current->mm. It's more
convenient, than passing this piece of state in other functions.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/io_uring.c | 37 |
1 files changed, 16 insertions, 21 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 81532479c857..f7825d3de400 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -5812,8 +5812,7 @@ static void io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, } static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, - struct file *ring_file, int ring_fd, - struct mm_struct **mm, bool async) + struct file *ring_file, int ring_fd, bool async) { struct io_submit_state state, *statep = NULL; struct io_kiocb *link = NULL; @@ -5870,13 +5869,12 @@ fail_req: break; } - if (io_op_defs[req->opcode].needs_mm && !*mm) { + if (io_op_defs[req->opcode].needs_mm && !current->mm) { if (unlikely(!mmget_not_zero(ctx->sqo_mm))) { err = -EFAULT; goto fail_req; } use_mm(ctx->sqo_mm); - *mm = ctx->sqo_mm; } req->needs_fixed_file = async; @@ -5902,10 +5900,19 @@ fail_req: return submitted; } +static inline void io_sq_thread_drop_mm(struct io_ring_ctx *ctx) +{ + struct mm_struct *mm = current->mm; + + if (mm) { + unuse_mm(mm); + mmput(mm); + } +} + static int io_sq_thread(void *data) { struct io_ring_ctx *ctx = data; - struct mm_struct *cur_mm = NULL; const struct cred *old_cred; mm_segment_t old_fs; DEFINE_WAIT(wait); @@ -5946,11 +5953,7 @@ static int io_sq_thread(void *data) * adding ourselves to the waitqueue, as the unuse/drop * may sleep. */ - if (cur_mm) { - unuse_mm(cur_mm); - mmput(cur_mm); - cur_mm = NULL; - } + io_sq_thread_drop_mm(ctx); /* * We're polling. If we're within the defined idle @@ -6014,7 +6017,7 @@ static int io_sq_thread(void *data) } mutex_lock(&ctx->uring_lock); - ret = io_submit_sqes(ctx, to_submit, NULL, -1, &cur_mm, true); + ret = io_submit_sqes(ctx, to_submit, NULL, -1, true); mutex_unlock(&ctx->uring_lock); timeout = jiffies + ctx->sq_thread_idle; } @@ -6023,10 +6026,7 @@ static int io_sq_thread(void *data) task_work_run(); set_fs(old_fs); - if (cur_mm) { - unuse_mm(cur_mm); - mmput(cur_mm); - } + io_sq_thread_drop_mm(ctx); revert_creds(old_cred); kthread_parkme(); @@ -7507,13 +7507,8 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, wake_up(&ctx->sqo_wait); submitted = to_submit; } else if (to_submit) { - struct mm_struct *cur_mm; - mutex_lock(&ctx->uring_lock); - /* already have mm, so io_submit_sqes() won't try to grab it */ - cur_mm = ctx->sqo_mm; - submitted = io_submit_sqes(ctx, to_submit, f.file, fd, - &cur_mm, false); + submitted = io_submit_sqes(ctx, to_submit, f.file, fd, false); mutex_unlock(&ctx->uring_lock); if (submitted != to_submit) |