From cccf0ee834559ae0b327b40290e14f6a2a017177 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 27 Jan 2020 16:34:48 -0700 Subject: io_uring/io-wq: don't use static creds/mm assignments We currently setup the io_wq with a static set of mm and creds. Even for a single-use io-wq per io_uring, this is suboptimal as we have may have multiple enters of the ring. For sharing the io-wq backend, it doesn't work at all. Switch to passing in the creds and mm when the work item is setup. This means that async work is no longer deferred to the io_uring mm and creds, it is done with the current mm and creds. Flag this behavior with IORING_FEAT_CUR_PERSONALITY, so applications know they can rely on the current personality (mm and creds) being the same for direct issue and async issue. Reviewed-by: Stefan Metzmacher Signed-off-by: Jens Axboe --- fs/io-wq.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'fs/io-wq.h') diff --git a/fs/io-wq.h b/fs/io-wq.h index 1cd039af8813..167316ad447e 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -7,7 +7,6 @@ enum { IO_WQ_WORK_CANCEL = 1, IO_WQ_WORK_HAS_MM = 2, IO_WQ_WORK_HASHED = 4, - IO_WQ_WORK_NEEDS_USER = 8, IO_WQ_WORK_NEEDS_FILES = 16, IO_WQ_WORK_UNBOUND = 32, IO_WQ_WORK_INTERNAL = 64, @@ -74,6 +73,8 @@ struct io_wq_work { }; void (*func)(struct io_wq_work **); struct files_struct *files; + struct mm_struct *mm; + const struct cred *creds; unsigned flags; }; @@ -83,15 +84,15 @@ struct io_wq_work { (work)->func = _func; \ (work)->flags = 0; \ (work)->files = NULL; \ + (work)->mm = NULL; \ + (work)->creds = NULL; \ } while (0) \ typedef void (get_work_fn)(struct io_wq_work *); typedef void (put_work_fn)(struct io_wq_work *); struct io_wq_data { - struct mm_struct *mm; struct user_struct *user; - const struct cred *creds; get_work_fn *get_work; put_work_fn *put_work; -- cgit