#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
+#include <scsi/sg.h> /* for struct sg_iovec */
#include "blk.h"
}
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, gfp_t gfp_mask)
{
unsigned long uaddr;
struct bio *bio, *orig_bio;
* direct dma. else, set up kernel bounce buffers
*/
uaddr = (unsigned long) ubuf;
- if (!(uaddr & queue_dma_alignment(q)) &&
- !(len & queue_dma_alignment(q)))
- 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 (map_data && map_data->null_mapped)
+ bio->bi_flags |= (1 << BIO_NULL_MAPPED);
+
orig_bio = bio;
blk_queue_bounce(q, &bio);
}
/**
- * 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()
* 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;
if (len > (q->max_hw_sectors << 9))
return -EINVAL;
- if (!len || !ubuf)
+ if (!len)
+ return -EINVAL;
+
+ if (!ubuf && (!map_data || !map_data->null_mapped))
return -EINVAL;
while (bytes_read != len) {
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,
+ gfp_mask);
if (ret < 0)
goto unmap_rq;
if (!bio)
bio = rq->bio;
bytes_read += ret;
ubuf += ret;
- }
-
- /*
- * __blk_rq_map_user() copies the buffers if starting address
- * or length isn't aligned. As the copied buffer is always
- * page aligned, we know that there's enough room for padding.
- * Extend the last bio and update rq->data_len accordingly.
- *
- * On unmap, bio_uncopy_user() will use unmodified
- * bio_map_data pointed to by bio->bi_private.
- */
- if (len & queue_dma_alignment(q)) {
- unsigned int pad_len = (queue_dma_alignment(q) & ~len) + 1;
- rq->extra_len += pad_len;
+ if (map_data)
+ map_data->offset += ret;
}
+ if (!bio_flagged(bio, BIO_USER_MAPPED))
+ rq->cmd_flags |= REQ_COPY_USER;
+
rq->buffer = rq->data = NULL;
return 0;
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()
* 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;
+ int unaligned = 0;
if (!iov || iov_count <= 0)
return -EINVAL;
- /* we don't allow misaligned data like bio_map_user() does. If the
- * user is using sg, they're expected to know the alignment constraints
- * and respect them accordingly */
- bio = bio_map_user_iov(q, NULL, iov, iov_count,
- rq_data_dir(rq) == READ);
+ for (i = 0; i < iov_count; i++) {
+ unsigned long uaddr = (unsigned long)iov[i].iov_base;
+
+ if (uaddr & queue_dma_alignment(q)) {
+ unaligned = 1;
+ break;
+ }
+ }
+
+ 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, gfp_mask);
+
if (IS_ERR(bio))
return PTR_ERR(bio);
if (bio->bi_size != len) {
+ /*
+ * Grab an extra reference to this bio, as bio_unmap_user()
+ * expects to be able to drop it twice as it happens on the
+ * normal IO completion path
+ */
+ bio_get(bio);
bio_endio(bio, 0);
- bio_unmap_user(bio);
+ __blk_rq_unmap_user(bio);
return -EINVAL;
}
+ if (!bio_flagged(bio, BIO_USER_MAPPED))
+ rq->cmd_flags |= REQ_COPY_USER;
+
+ blk_queue_bounce(q, &bio);
bio_get(bio);
blk_rq_bio_prep(q, rq, bio);
rq->buffer = rq->data = NULL;
* 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)
{
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
* @len: length of user data
* @gfp_mask: memory allocation flags
+ *
+ * Description:
+ * Data will be mapped directly if possible. Otherwise a bounce
+ * buffer is used.
*/
int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
unsigned int len, gfp_t gfp_mask)
{
+ int reading = rq_data_dir(rq) == READ;
+ int do_copy = 0;
struct bio *bio;
if (len > (q->max_hw_sectors << 9))
if (!len || !kbuf)
return -EINVAL;
- bio = bio_map_kern(q, kbuf, len, gfp_mask);
+ 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
+ bio = bio_map_kern(q, kbuf, len, gfp_mask);
+
if (IS_ERR(bio))
return PTR_ERR(bio);
if (rq_data_dir(rq) == WRITE)
bio->bi_rw |= (1 << BIO_RW);
+ if (do_copy)
+ rq->cmd_flags |= REQ_COPY_USER;
+
blk_rq_bio_prep(q, rq, bio);
blk_queue_bounce(q, &rq->bio);
rq->buffer = rq->data = NULL;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff