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Diffstat (limited to 'io_uring/kbuf.c')
-rw-r--r--io_uring/kbuf.c55
1 files changed, 23 insertions, 32 deletions
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index 18df5a9d2f5e..693c26da4ee1 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -81,15 +81,6 @@ bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
struct io_buffer_list *bl;
struct io_buffer *buf;
- /*
- * For legacy provided buffer mode, don't recycle if we already did
- * IO to this buffer. For ring-mapped provided buffer mode, we should
- * increment ring->head to explicitly monopolize the buffer to avoid
- * multiple use.
- */
- if (req->flags & REQ_F_PARTIAL_IO)
- return false;
-
io_ring_submit_lock(ctx, issue_flags);
buf = req->kbuf;
@@ -102,10 +93,8 @@ bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
return true;
}
-unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)
+void __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)
{
- unsigned int cflags;
-
/*
* We can add this buffer back to two lists:
*
@@ -118,21 +107,17 @@ unsigned int __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)
* We migrate buffers from the comp_list to the issue cache list
* when we need one.
*/
- if (req->flags & REQ_F_BUFFER_RING) {
- /* no buffers to recycle for this case */
- cflags = __io_put_kbuf_list(req, NULL);
- } else if (issue_flags & IO_URING_F_UNLOCKED) {
+ if (issue_flags & IO_URING_F_UNLOCKED) {
struct io_ring_ctx *ctx = req->ctx;
spin_lock(&ctx->completion_lock);
- cflags = __io_put_kbuf_list(req, &ctx->io_buffers_comp);
+ __io_put_kbuf_list(req, &ctx->io_buffers_comp);
spin_unlock(&ctx->completion_lock);
} else {
lockdep_assert_held(&req->ctx->uring_lock);
- cflags = __io_put_kbuf_list(req, &req->ctx->io_buffers_cache);
+ __io_put_kbuf_list(req, &req->ctx->io_buffers_cache);
}
- return cflags;
}
static void __user *io_provided_buffer_select(struct io_kiocb *req, size_t *len,
@@ -145,6 +130,8 @@ static void __user *io_provided_buffer_select(struct io_kiocb *req, size_t *len,
list_del(&kbuf->list);
if (*len == 0 || *len > kbuf->len)
*len = kbuf->len;
+ if (list_empty(&bl->buf_list))
+ req->flags |= REQ_F_BL_EMPTY;
req->flags |= REQ_F_BUFFER_SELECTED;
req->kbuf = kbuf;
req->buf_index = kbuf->bid;
@@ -158,12 +145,16 @@ static void __user *io_ring_buffer_select(struct io_kiocb *req, size_t *len,
unsigned int issue_flags)
{
struct io_uring_buf_ring *br = bl->buf_ring;
+ __u16 tail, head = bl->head;
struct io_uring_buf *buf;
- __u16 head = bl->head;
- if (unlikely(smp_load_acquire(&br->tail) == head))
+ tail = smp_load_acquire(&br->tail);
+ if (unlikely(tail == head))
return NULL;
+ if (head + 1 == tail)
+ req->flags |= REQ_F_BL_EMPTY;
+
head &= bl->mask;
/* mmaped buffers are always contig */
if (bl->is_mmap || head < IO_BUFFER_LIST_BUF_PER_PAGE) {
@@ -180,7 +171,7 @@ static void __user *io_ring_buffer_select(struct io_kiocb *req, size_t *len,
req->buf_list = bl;
req->buf_index = buf->bid;
- if (issue_flags & IO_URING_F_UNLOCKED || !file_can_poll(req->file)) {
+ if (issue_flags & IO_URING_F_UNLOCKED || !io_file_can_poll(req)) {
/*
* If we came in unlocked, we have no choice but to consume the
* buffer here, otherwise nothing ensures that the buffer won't
@@ -208,7 +199,7 @@ void __user *io_buffer_select(struct io_kiocb *req, size_t *len,
bl = io_buffer_get_list(ctx, req->buf_index);
if (likely(bl)) {
- if (bl->is_mapped)
+ if (bl->is_buf_ring)
ret = io_ring_buffer_select(req, len, bl, issue_flags);
else
ret = io_provided_buffer_select(req, len, bl);
@@ -262,7 +253,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx,
if (!nbufs)
return 0;
- if (bl->is_mapped) {
+ if (bl->is_buf_ring) {
i = bl->buf_ring->tail - bl->head;
if (bl->is_mmap) {
/*
@@ -283,7 +274,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx,
}
/* make sure it's seen as empty */
INIT_LIST_HEAD(&bl->buf_list);
- bl->is_mapped = 0;
+ bl->is_buf_ring = 0;
return i;
}
@@ -370,7 +361,7 @@ int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
if (bl) {
ret = -EINVAL;
/* can't use provide/remove buffers command on mapped buffers */
- if (!bl->is_mapped)
+ if (!bl->is_buf_ring)
ret = __io_remove_buffers(ctx, bl, p->nbufs);
}
io_ring_submit_unlock(ctx, issue_flags);
@@ -528,7 +519,7 @@ int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
}
}
/* can't add buffers via this command for a mapped buffer ring */
- if (bl->is_mapped) {
+ if (bl->is_buf_ring) {
ret = -EINVAL;
goto err;
}
@@ -584,7 +575,7 @@ static int io_pin_pbuf_ring(struct io_uring_buf_reg *reg,
bl->buf_pages = pages;
bl->buf_nr_pages = nr_pages;
bl->buf_ring = br;
- bl->is_mapped = 1;
+ bl->is_buf_ring = 1;
bl->is_mmap = 0;
return 0;
error_unpin:
@@ -651,7 +642,7 @@ static int io_alloc_pbuf_ring(struct io_ring_ctx *ctx,
}
ibf->inuse = 1;
bl->buf_ring = ibf->mem;
- bl->is_mapped = 1;
+ bl->is_buf_ring = 1;
bl->is_mmap = 1;
return 0;
}
@@ -697,7 +688,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
bl = io_buffer_get_list(ctx, reg.bgid);
if (bl) {
/* if mapped buffer ring OR classic exists, don't allow */
- if (bl->is_mapped || !list_empty(&bl->buf_list))
+ if (bl->is_buf_ring || !list_empty(&bl->buf_list))
return -EEXIST;
} else {
free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL);
@@ -739,7 +730,7 @@ int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
bl = io_buffer_get_list(ctx, reg.bgid);
if (!bl)
return -ENOENT;
- if (!bl->is_mapped)
+ if (!bl->is_buf_ring)
return -EINVAL;
__io_remove_buffers(ctx, bl, -1U);
@@ -766,7 +757,7 @@ int io_register_pbuf_status(struct io_ring_ctx *ctx, void __user *arg)
bl = io_buffer_get_list(ctx, buf_status.buf_group);
if (!bl)
return -ENOENT;
- if (!bl->is_mapped)
+ if (!bl->is_buf_ring)
return -EINVAL;
buf_status.head = bl->head;
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-01 11:19:08 +0000