6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jens Axboe axboe@kernel.dk
commit 09ab7eff38202159271534d2f5ad45526168f2a5 upstream.
Just rely on the xarray for any kind of bgid. This simplifies things, and it really doesn't bring us much, if anything.
Cc: stable@vger.kernel.org # v6.4+ Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/io_uring_types.h | 1 io_uring/io_uring.c | 2 - io_uring/kbuf.c | 70 ++++------------------------------------- 3 files changed, 8 insertions(+), 65 deletions(-)
--- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -250,7 +250,6 @@ struct io_ring_ctx {
struct io_submit_state submit_state;
- struct io_buffer_list *io_bl; struct xarray io_bl_xa;
struct io_hash_table cancel_table_locked; --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -343,7 +343,6 @@ static __cold struct io_ring_ctx *io_rin err: kfree(ctx->cancel_table.hbs); kfree(ctx->cancel_table_locked.hbs); - kfree(ctx->io_bl); xa_destroy(&ctx->io_bl_xa); kfree(ctx); return NULL; @@ -2934,7 +2933,6 @@ static __cold void io_ring_ctx_free(stru io_wq_put_hash(ctx->hash_map); kfree(ctx->cancel_table.hbs); kfree(ctx->cancel_table_locked.hbs); - kfree(ctx->io_bl); xa_destroy(&ctx->io_bl_xa); kfree(ctx); } --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -17,8 +17,6 @@
#define IO_BUFFER_LIST_BUF_PER_PAGE (PAGE_SIZE / sizeof(struct io_uring_buf))
-#define BGID_ARRAY 64 - /* BIDs are addressed by a 16-bit field in a CQE */ #define MAX_BIDS_PER_BGID (1 << 16)
@@ -31,13 +29,9 @@ struct io_provide_buf { __u16 bid; };
-static struct io_buffer_list *__io_buffer_get_list(struct io_ring_ctx *ctx, - struct io_buffer_list *bl, - unsigned int bgid) +static inline struct io_buffer_list *__io_buffer_get_list(struct io_ring_ctx *ctx, + unsigned int bgid) { - if (bl && bgid < BGID_ARRAY) - return &bl[bgid]; - return xa_load(&ctx->io_bl_xa, bgid); }
@@ -53,7 +47,7 @@ static inline struct io_buffer_list *io_ { lockdep_assert_held(&ctx->uring_lock);
- return __io_buffer_get_list(ctx, ctx->io_bl, bgid); + return __io_buffer_get_list(ctx, bgid); }
static int io_buffer_add_list(struct io_ring_ctx *ctx, @@ -66,10 +60,6 @@ static int io_buffer_add_list(struct io_ */ bl->bgid = bgid; smp_store_release(&bl->is_ready, 1); - - if (bgid < BGID_ARRAY) - return 0; - return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL)); }
@@ -215,24 +205,6 @@ void __user *io_buffer_select(struct io_ return ret; }
-static __cold int io_init_bl_list(struct io_ring_ctx *ctx) -{ - struct io_buffer_list *bl; - int i; - - bl = kcalloc(BGID_ARRAY, sizeof(struct io_buffer_list), GFP_KERNEL); - if (!bl) - return -ENOMEM; - - for (i = 0; i < BGID_ARRAY; i++) { - INIT_LIST_HEAD(&bl[i].buf_list); - bl[i].bgid = i; - } - - smp_store_release(&ctx->io_bl, bl); - return 0; -} - /* * Mark the given mapped range as free for reuse */ @@ -305,13 +277,6 @@ void io_destroy_buffers(struct io_ring_c { struct io_buffer_list *bl; unsigned long index; - int i; - - for (i = 0; i < BGID_ARRAY; i++) { - if (!ctx->io_bl) - break; - __io_remove_buffers(ctx, &ctx->io_bl[i], -1U); - }
xa_for_each(&ctx->io_bl_xa, index, bl) { xa_erase(&ctx->io_bl_xa, bl->bgid); @@ -485,12 +450,6 @@ int io_provide_buffers(struct io_kiocb *
io_ring_submit_lock(ctx, issue_flags);
- if (unlikely(p->bgid < BGID_ARRAY && !ctx->io_bl)) { - ret = io_init_bl_list(ctx); - if (ret) - goto err; - } - bl = io_buffer_get_list(ctx, p->bgid); if (unlikely(!bl)) { bl = kzalloc(sizeof(*bl), GFP_KERNEL_ACCOUNT); @@ -503,14 +462,9 @@ int io_provide_buffers(struct io_kiocb * if (ret) { /* * Doesn't need rcu free as it was never visible, but - * let's keep it consistent throughout. Also can't - * be a lower indexed array group, as adding one - * where lookup failed cannot happen. + * let's keep it consistent throughout. */ - if (p->bgid >= BGID_ARRAY) - kfree_rcu(bl, rcu); - else - WARN_ON_ONCE(1); + kfree_rcu(bl, rcu); goto err; } } @@ -675,12 +629,6 @@ int io_register_pbuf_ring(struct io_ring if (reg.ring_entries >= 65536) return -EINVAL;
- if (unlikely(reg.bgid < BGID_ARRAY && !ctx->io_bl)) { - int ret = io_init_bl_list(ctx); - if (ret) - return ret; - } - bl = io_buffer_get_list(ctx, reg.bgid); if (bl) { /* if mapped buffer ring OR classic exists, don't allow */ @@ -730,10 +678,8 @@ int io_unregister_pbuf_ring(struct io_ri return -EINVAL;
__io_remove_buffers(ctx, bl, -1U); - if (bl->bgid >= BGID_ARRAY) { - xa_erase(&ctx->io_bl_xa, bl->bgid); - kfree_rcu(bl, rcu); - } + xa_erase(&ctx->io_bl_xa, bl->bgid); + kfree_rcu(bl, rcu); return 0; }
@@ -741,7 +687,7 @@ void *io_pbuf_get_address(struct io_ring { struct io_buffer_list *bl;
- bl = __io_buffer_get_list(ctx, smp_load_acquire(&ctx->io_bl), bgid); + bl = __io_buffer_get_list(ctx, bgid);
if (!bl || !bl->is_mmap) return NULL;