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-rw-r--r--block/blk-map.c68
1 files changed, 39 insertions, 29 deletions
diff --git a/block/blk-map.c b/block/blk-map.c
index af37e4ae62f..4849fa36161 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -41,10 +41,10 @@ static int __blk_rq_unmap_user(struct bio *bio)
}
static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
- void __user *ubuf, unsigned int len)
+ struct rq_map_data *map_data, void __user *ubuf,
+ unsigned int len, int null_mapped, gfp_t gfp_mask)
{
unsigned long uaddr;
- unsigned int alignment;
struct bio *bio, *orig_bio;
int reading, ret;
@@ -55,15 +55,17 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
* direct dma. else, set up kernel bounce buffers
*/
uaddr = (unsigned long) ubuf;
- alignment = queue_dma_alignment(q) | q->dma_pad_mask;
- if (!(uaddr & alignment) && !(len & alignment))
- bio = bio_map_user(q, NULL, uaddr, len, reading);
+ if (blk_rq_aligned(q, ubuf, len) && !map_data)
+ bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);
else
- bio = bio_copy_user(q, uaddr, len, reading);
+ bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
if (IS_ERR(bio))
return PTR_ERR(bio);
+ if (null_mapped)
+ bio->bi_flags |= (1 << BIO_NULL_MAPPED);
+
orig_bio = bio;
blk_queue_bounce(q, &bio);
@@ -85,17 +87,19 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
}
/**
- * blk_rq_map_user - map user data to a request, for REQ_BLOCK_PC usage
+ * blk_rq_map_user - map user data to a request, for REQ_TYPE_BLOCK_PC usage
* @q: request queue where request should be inserted
* @rq: request structure to fill
+ * @map_data: pointer to the rq_map_data holding pages (if necessary)
* @ubuf: the user buffer
* @len: length of user data
+ * @gfp_mask: memory allocation flags
*
* Description:
- * Data will be mapped directly for zero copy io, if possible. Otherwise
+ * Data will be mapped directly for zero copy I/O, if possible. Otherwise
* a kernel bounce buffer is used.
*
- * A matching blk_rq_unmap_user() must be issued at the end of io, while
+ * A matching blk_rq_unmap_user() must be issued at the end of I/O, while
* still in process context.
*
* Note: The mapped bio may need to be bounced through blk_queue_bounce()
@@ -105,16 +109,22 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
* unmapping.
*/
int blk_rq_map_user(struct request_queue *q, struct request *rq,
- void __user *ubuf, unsigned long len)
+ struct rq_map_data *map_data, void __user *ubuf,
+ unsigned long len, gfp_t gfp_mask)
{
unsigned long bytes_read = 0;
struct bio *bio = NULL;
- int ret;
+ int ret, null_mapped = 0;
if (len > (q->max_hw_sectors << 9))
return -EINVAL;
- if (!len || !ubuf)
+ if (!len)
return -EINVAL;
+ if (!ubuf) {
+ if (!map_data || rq_data_dir(rq) != READ)
+ return -EINVAL;
+ null_mapped = 1;
+ }
while (bytes_read != len) {
unsigned long map_len, end, start;
@@ -132,7 +142,8 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
if (end - start > BIO_MAX_PAGES)
map_len -= PAGE_SIZE;
- ret = __blk_rq_map_user(q, rq, ubuf, map_len);
+ ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,
+ null_mapped, gfp_mask);
if (ret < 0)
goto unmap_rq;
if (!bio)
@@ -154,18 +165,20 @@ unmap_rq:
EXPORT_SYMBOL(blk_rq_map_user);
/**
- * blk_rq_map_user_iov - map user data to a request, for REQ_BLOCK_PC usage
+ * blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_BLOCK_PC usage
* @q: request queue where request should be inserted
* @rq: request to map data to
+ * @map_data: pointer to the rq_map_data holding pages (if necessary)
* @iov: pointer to the iovec
* @iov_count: number of elements in the iovec
* @len: I/O byte count
+ * @gfp_mask: memory allocation flags
*
* Description:
- * Data will be mapped directly for zero copy io, if possible. Otherwise
+ * Data will be mapped directly for zero copy I/O, if possible. Otherwise
* a kernel bounce buffer is used.
*
- * A matching blk_rq_unmap_user() must be issued at the end of io, while
+ * A matching blk_rq_unmap_user() must be issued at the end of I/O, while
* still in process context.
*
* Note: The mapped bio may need to be bounced through blk_queue_bounce()
@@ -175,7 +188,8 @@ EXPORT_SYMBOL(blk_rq_map_user);
* unmapping.
*/
int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
- struct sg_iovec *iov, int iov_count, unsigned int len)
+ struct rq_map_data *map_data, struct sg_iovec *iov,
+ int iov_count, unsigned int len, gfp_t gfp_mask)
{
struct bio *bio;
int i, read = rq_data_dir(rq) == READ;
@@ -193,10 +207,11 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
}
}
- if (unaligned || (q->dma_pad_mask & len))
- bio = bio_copy_user_iov(q, iov, iov_count, read);
+ if (unaligned || (q->dma_pad_mask & len) || map_data)
+ bio = bio_copy_user_iov(q, map_data, iov, iov_count, read,
+ gfp_mask);
else
- bio = bio_map_user_iov(q, NULL, iov, iov_count, read);
+ bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask);
if (IS_ERR(bio))
return PTR_ERR(bio);
@@ -216,6 +231,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
rq->buffer = rq->data = NULL;
return 0;
}
+EXPORT_SYMBOL(blk_rq_map_user_iov);
/**
* blk_rq_unmap_user - unmap a request with user data
@@ -224,7 +240,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
* Description:
* Unmap a rq previously mapped by blk_rq_map_user(). The caller must
* supply the original rq->bio from the blk_rq_map_user() return, since
- * the io completion may have changed rq->bio.
+ * the I/O completion may have changed rq->bio.
*/
int blk_rq_unmap_user(struct bio *bio)
{
@@ -250,7 +266,7 @@ int blk_rq_unmap_user(struct bio *bio)
EXPORT_SYMBOL(blk_rq_unmap_user);
/**
- * blk_rq_map_kern - map kernel data to a request, for REQ_BLOCK_PC usage
+ * blk_rq_map_kern - map kernel data to a request, for REQ_TYPE_BLOCK_PC usage
* @q: request queue where request should be inserted
* @rq: request to fill
* @kbuf: the kernel buffer
@@ -264,8 +280,6 @@ EXPORT_SYMBOL(blk_rq_unmap_user);
int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
unsigned int len, gfp_t gfp_mask)
{
- unsigned long kaddr;
- unsigned int alignment;
int reading = rq_data_dir(rq) == READ;
int do_copy = 0;
struct bio *bio;
@@ -275,11 +289,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
if (!len || !kbuf)
return -EINVAL;
- kaddr = (unsigned long)kbuf;
- alignment = queue_dma_alignment(q) | q->dma_pad_mask;
- do_copy = ((kaddr & alignment) || (len & alignment) ||
- object_is_on_stack(kbuf));
-
+ do_copy = !blk_rq_aligned(q, kbuf, len) || object_is_on_stack(kbuf);
if (do_copy)
bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading);
else