diff options
author | Jens Axboe <axboe@kernel.dk> | 2022-03-31 19:27:52 -0600 |
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committer | Jens Axboe <axboe@kernel.dk> | 2022-05-09 06:35:33 -0600 |
commit | ebdeb7c01d025cb059f05dc26b9dc914e46dd43f (patch) | |
tree | 277d08ae7ef441660c3287eba92195b05becea9d /fs/io_uring.c | |
parent | b5ba65df47cabcba6fe7a03f8f57513e9f78f72f (diff) | |
download | lwn-ebdeb7c01d025cb059f05dc26b9dc914e46dd43f.tar.gz lwn-ebdeb7c01d025cb059f05dc26b9dc914e46dd43f.zip |
io_uring: add support for 128-byte SQEs
Normal SQEs are 64-bytes in length, which is fine for all the commands
we support. However, in preparation for supporting passthrough IO,
provide an option for setting up a ring with 128-byte SQEs.
We continue to use the same type for io_uring_sqe, it's marked and
commented with a zero sized array pad at the end. This provides up
to 80 bytes of data for a passthrough command - 64 bytes for the
extra added data, and 16 bytes available at the end of the existing
SQE.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
-rw-r--r-- | fs/io_uring.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 53e54fc05488..106a0db56ddb 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -8519,8 +8519,12 @@ static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx) * though the application is the one updating it. */ head = READ_ONCE(ctx->sq_array[sq_idx]); - if (likely(head < ctx->sq_entries)) + if (likely(head < ctx->sq_entries)) { + /* double index for 128-byte SQEs, twice as long */ + if (ctx->flags & IORING_SETUP_SQE128) + head <<= 1; return &ctx->sq_sqes[head]; + } /* drop invalid entries */ ctx->cq_extra--; @@ -11689,7 +11693,10 @@ static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx, rings->sq_ring_entries = p->sq_entries; rings->cq_ring_entries = p->cq_entries; - size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); + if (p->flags & IORING_SETUP_SQE128) + size = array_size(2 * sizeof(struct io_uring_sqe), p->sq_entries); + else + size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); if (size == SIZE_MAX) { io_mem_free(ctx->rings); ctx->rings = NULL; @@ -11933,7 +11940,8 @@ static long io_uring_setup(u32 entries, struct io_uring_params __user *params) IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE | IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ | IORING_SETUP_R_DISABLED | IORING_SETUP_SUBMIT_ALL | - IORING_SETUP_COOP_TASKRUN | IORING_SETUP_TASKRUN_FLAG)) + IORING_SETUP_COOP_TASKRUN | IORING_SETUP_TASKRUN_FLAG | + IORING_SETUP_SQE128)) return -EINVAL; return io_uring_create(entries, &p, params); |