dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

block: introduce struct rq_map_data to use reserved pages 

This patch introduces struct rq_map_data to enable bio_copy_use_iov()
use reserved pages.

Currently, bio_copy_user_iov allocates bounce pages but
drivers/scsi/sg.c wants to allocate pages by itself and use
them. struct rq_map_data can be used to pass allocated pages to
bio_copy_user_iov.

The current users of bio_copy_user_iov simply passes NULL (they don't
want to use pre-allocated pages).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
FUJITA Tomonori 2008-08-28 16:17:06 +09:00 committed by Jens Axboe
parent a3bce90edd
commit 152e283fdf
8 changed files with 80 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
block/blk-map.c
View File

@ -41,8 +41,8 @@ static int __blk_rq_unmap_user(struct bio *bio)
} }
static int __blk_rq_map_user(struct request_queue *q, struct request *rq, 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,
gfp_t gfp_mask) unsigned int len, gfp_t gfp_mask)
{ {
unsigned long uaddr; unsigned long uaddr;
unsigned int alignment; unsigned int alignment;
@ -57,10 +57,10 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
*/ */
uaddr = (unsigned long) ubuf; uaddr = (unsigned long) ubuf;
alignment = queue_dma_alignment(q) | q->dma_pad_mask; alignment = queue_dma_alignment(q) | q->dma_pad_mask;
if (!(uaddr & alignment) && !(len & alignment)) if (!(uaddr & alignment) && !(len & alignment) && !map_data)
bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask); bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);
else else
bio = bio_copy_user(q, uaddr, len, reading, gfp_mask); bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
if (IS_ERR(bio)) if (IS_ERR(bio))
return PTR_ERR(bio); return PTR_ERR(bio);
@ -89,6 +89,7 @@ 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_TYPE_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 * @q: request queue where request should be inserted
* @rq: request structure to fill * @rq: request structure to fill
* @map_data: pointer to the rq_map_data holding pages (if necessary)
* @ubuf: the user buffer * @ubuf: the user buffer
* @len: length of user data * @len: length of user data
* @gfp_mask: memory allocation flags * @gfp_mask: memory allocation flags
@ -107,7 +108,8 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
* unmapping. * unmapping.
*/ */
int blk_rq_map_user(struct request_queue *q, struct request *rq, int blk_rq_map_user(struct request_queue *q, struct request *rq,
void __user *ubuf, unsigned long len, gfp_t gfp_mask) struct rq_map_data *map_data, void __user *ubuf,
unsigned long len, gfp_t gfp_mask)
{ {
unsigned long bytes_read = 0; unsigned long bytes_read = 0;
struct bio *bio = NULL; struct bio *bio = NULL;
@ -134,7 +136,8 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
if (end - start > BIO_MAX_PAGES) if (end - start > BIO_MAX_PAGES)
map_len -= PAGE_SIZE; map_len -= PAGE_SIZE;
ret = __blk_rq_map_user(q, rq, ubuf, map_len, gfp_mask); ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,
gfp_mask);
if (ret < 0) if (ret < 0)
goto unmap_rq; goto unmap_rq;
if (!bio) if (!bio)
@ -159,6 +162,7 @@ EXPORT_SYMBOL(blk_rq_map_user);
* blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_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 * @q: request queue where request should be inserted
* @rq: request to map data to * @rq: request to map data to
* @map_data: pointer to the rq_map_data holding pages (if necessary)
* @iov: pointer to the iovec * @iov: pointer to the iovec
* @iov_count: number of elements in the iovec * @iov_count: number of elements in the iovec
* @len: I/O byte count * @len: I/O byte count
@ -178,8 +182,8 @@ EXPORT_SYMBOL(blk_rq_map_user);
* unmapping. * unmapping.
*/ */
int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, 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,
gfp_t gfp_mask) int iov_count, unsigned int len, gfp_t gfp_mask)
{ {
struct bio *bio; struct bio *bio;
int i, read = rq_data_dir(rq) == READ; int i, read = rq_data_dir(rq) == READ;
@ -197,8 +201,9 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
} }
} }
if (unaligned || (q->dma_pad_mask & len)) if (unaligned || (q->dma_pad_mask & len) || map_data)
bio = bio_copy_user_iov(q, iov, iov_count, read, gfp_mask); bio = bio_copy_user_iov(q, map_data, iov, iov_count, read,
gfp_mask);
else else
bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask); bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask);
@ -220,6 +225,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
rq->buffer = rq->data = NULL; rq->buffer = rq->data = NULL;
return 0; return 0;
} }
EXPORT_SYMBOL(blk_rq_map_user_iov);
/** /**
* blk_rq_unmap_user - unmap a request with user data * blk_rq_unmap_user - unmap a request with user data

7
block/bsg.c
View File

@ -283,8 +283,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm)
next_rq->cmd_type = rq->cmd_type; next_rq->cmd_type = rq->cmd_type;
dxferp = (void*)(unsigned long)hdr->din_xferp; dxferp = (void*)(unsigned long)hdr->din_xferp;
ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len, ret = blk_rq_map_user(q, next_rq, NULL, dxferp,
GFP_KERNEL); hdr->din_xfer_len, GFP_KERNEL);
if (ret) if (ret)
goto out; goto out;
} }
@ -299,7 +299,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm)
dxfer_len = 0; dxfer_len = 0;
if (dxfer_len) { if (dxfer_len) {
ret = blk_rq_map_user(q, rq, dxferp, dxfer_len, GFP_KERNEL); ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
GFP_KERNEL);
if (ret) if (ret)
goto out; goto out;
} }

4
block/scsi_ioctl.c
View File

@ -314,11 +314,11 @@ static int sg_io(struct file *file, struct request_queue *q,
goto out; goto out;
} }
ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count, ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count,
hdr->dxfer_len, GFP_KERNEL); hdr->dxfer_len, GFP_KERNEL);
kfree(iov); kfree(iov);
} else if (hdr->dxfer_len) } else if (hdr->dxfer_len)
ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len, ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
GFP_KERNEL); GFP_KERNEL);
if (ret) if (ret)

2
drivers/cdrom/cdrom.c
View File

@ -2097,7 +2097,7 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf,
len = nr * CD_FRAMESIZE_RAW; len = nr * CD_FRAMESIZE_RAW;
ret = blk_rq_map_user(q, rq, ubuf, len, GFP_KERNEL); ret = blk_rq_map_user(q, rq, NULL, ubuf, len, GFP_KERNEL);
if (ret) if (ret)
break; break;

2
drivers/scsi/scsi_tgt_lib.c
View File

@ -362,7 +362,7 @@ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd,
int err; int err;
dprintk("%lx %u\n", uaddr, len); dprintk("%lx %u\n", uaddr, len);
err = blk_rq_map_user(q, rq, (void *)uaddr, len, GFP_KERNEL); err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL);
if (err) { if (err) {
/* /*
* TODO: need to fixup sg_tablesize, max_segment_size, * TODO: need to fixup sg_tablesize, max_segment_size,

58
fs/bio.c
View File

@ -439,16 +439,19 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
struct bio_map_data { struct bio_map_data {
struct bio_vec *iovecs; struct bio_vec *iovecs;
int nr_sgvecs;
struct sg_iovec *sgvecs; struct sg_iovec *sgvecs;
int nr_sgvecs;
int is_our_pages;
}; };
static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio, static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
struct sg_iovec *iov, int iov_count) struct sg_iovec *iov, int iov_count,
int is_our_pages)
{ {
memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt); memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt);
memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count); memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
bmd->nr_sgvecs = iov_count; bmd->nr_sgvecs = iov_count;
bmd->is_our_pages = is_our_pages;
bio->bi_private = bmd; bio->bi_private = bmd;
} }
@ -483,7 +486,8 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
} }
static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
struct sg_iovec *iov, int iov_count, int uncopy) struct sg_iovec *iov, int iov_count, int uncopy,
int do_free_page)
{ {
int ret = 0, i; int ret = 0, i;
struct bio_vec *bvec; struct bio_vec *bvec;
@ -526,7 +530,7 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
} }
} }
if (uncopy) if (do_free_page)
__free_page(bvec->bv_page); __free_page(bvec->bv_page);
} }
@ -545,7 +549,8 @@ int bio_uncopy_user(struct bio *bio)
struct bio_map_data *bmd = bio->bi_private; struct bio_map_data *bmd = bio->bi_private;
int ret; int ret;
ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1); ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1,
bmd->is_our_pages);
bio_free_map_data(bmd); bio_free_map_data(bmd);
bio_put(bio); bio_put(bio);
@ -555,6 +560,7 @@ int bio_uncopy_user(struct bio *bio)
/** /**
* bio_copy_user_iov - copy user data to bio * bio_copy_user_iov - copy user data to bio
* @q: destination block queue * @q: destination block queue
* @map_data: pointer to the rq_map_data holding pages (if necessary)
* @iov: the iovec. * @iov: the iovec.
* @iov_count: number of elements in the iovec * @iov_count: number of elements in the iovec
* @write_to_vm: bool indicating writing to pages or not * @write_to_vm: bool indicating writing to pages or not
@ -564,8 +570,10 @@ int bio_uncopy_user(struct bio *bio)
* to/from kernel pages as necessary. Must be paired with * to/from kernel pages as necessary. Must be paired with
* call bio_uncopy_user() on io completion. * call bio_uncopy_user() on io completion.
*/ */
struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, struct bio *bio_copy_user_iov(struct request_queue *q,
int iov_count, int write_to_vm, gfp_t gfp_mask) struct rq_map_data *map_data,
struct sg_iovec *iov, int iov_count,
int write_to_vm, gfp_t gfp_mask)
{ {
struct bio_map_data *bmd; struct bio_map_data *bmd;
struct bio_vec *bvec; struct bio_vec *bvec;
@ -600,13 +608,26 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov,
bio->bi_rw |= (!write_to_vm << BIO_RW); bio->bi_rw |= (!write_to_vm << BIO_RW);
ret = 0; ret = 0;
i = 0;
while (len) { while (len) {
unsigned int bytes = PAGE_SIZE; unsigned int bytes;
if (map_data)
bytes = 1U << (PAGE_SHIFT + map_data->page_order);
else
bytes = PAGE_SIZE;
if (bytes > len) if (bytes > len)
bytes = len; bytes = len;
page = alloc_page(q->bounce_gfp | gfp_mask); if (map_data) {
if (i == map_data->nr_entries) {
ret = -ENOMEM;
break;
}
page = map_data->pages[i++];
} else
page = alloc_page(q->bounce_gfp | gfp_mask);
if (!page) { if (!page) {
ret = -ENOMEM; ret = -ENOMEM;
break; break;
@ -625,16 +646,17 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov,
* success * success
*/ */
if (!write_to_vm) { if (!write_to_vm) {
ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0); ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0);
if (ret) if (ret)
goto cleanup; goto cleanup;
} }
bio_set_map_data(bmd, bio, iov, iov_count); bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1);
return bio; return bio;
cleanup: cleanup:
bio_for_each_segment(bvec, bio, i) if (!map_data)
__free_page(bvec->bv_page); bio_for_each_segment(bvec, bio, i)
__free_page(bvec->bv_page);
bio_put(bio); bio_put(bio);
out_bmd: out_bmd:
@ -645,6 +667,7 @@ out_bmd:
/** /**
* bio_copy_user - copy user data to bio * bio_copy_user - copy user data to bio
* @q: destination block queue * @q: destination block queue
* @map_data: pointer to the rq_map_data holding pages (if necessary)
* @uaddr: start of user address * @uaddr: start of user address
* @len: length in bytes * @len: length in bytes
* @write_to_vm: bool indicating writing to pages or not * @write_to_vm: bool indicating writing to pages or not
@ -654,15 +677,16 @@ out_bmd:
* to/from kernel pages as necessary. Must be paired with * to/from kernel pages as necessary. Must be paired with
* call bio_uncopy_user() on io completion. * call bio_uncopy_user() on io completion.
*/ */
struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr, struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
unsigned int len, int write_to_vm, gfp_t gfp_mask) unsigned long uaddr, unsigned int len,
int write_to_vm, gfp_t gfp_mask)
{ {
struct sg_iovec iov; struct sg_iovec iov;
iov.iov_base = (void __user *)uaddr; iov.iov_base = (void __user *)uaddr;
iov.iov_len = len; iov.iov_len = len;
return bio_copy_user_iov(q, &iov, 1, write_to_vm, gfp_mask); return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask);
} }
static struct bio *__bio_map_user_iov(struct request_queue *q, static struct bio *__bio_map_user_iov(struct request_queue *q,
@ -1028,7 +1052,7 @@ struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len,
bio->bi_private = bmd; bio->bi_private = bmd;
bio->bi_end_io = bio_copy_kern_endio; bio->bi_end_io = bio_copy_kern_endio;
bio_set_map_data(bmd, bio, &iov, 1); bio_set_map_data(bmd, bio, &iov, 1, 1);
return bio; return bio;
cleanup: cleanup:
bio_for_each_segment(bvec, bio, i) bio_for_each_segment(bvec, bio, i)

8
include/linux/bio.h
View File

@ -327,6 +327,7 @@ extern int bio_get_nr_vecs(struct block_device *);
extern struct bio *bio_map_user(struct request_queue *, struct block_device *, extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
unsigned long, unsigned int, int, gfp_t); unsigned long, unsigned int, int, gfp_t);
struct sg_iovec; struct sg_iovec;
struct rq_map_data;
extern struct bio *bio_map_user_iov(struct request_queue *, extern struct bio *bio_map_user_iov(struct request_queue *,
struct block_device *, struct block_device *,
struct sg_iovec *, int, int, gfp_t); struct sg_iovec *, int, int, gfp_t);
@ -337,9 +338,10 @@ extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
gfp_t, int); gfp_t, int);
extern void bio_set_pages_dirty(struct bio *bio); extern void bio_set_pages_dirty(struct bio *bio);
extern void bio_check_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio);
extern struct bio *bio_copy_user(struct request_queue *, unsigned long, extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
unsigned int, int, gfp_t); unsigned long, unsigned int, int, gfp_t);
extern struct bio *bio_copy_user_iov(struct request_queue *, struct sg_iovec *, extern struct bio *bio_copy_user_iov(struct request_queue *,
struct rq_map_data *, struct sg_iovec *,
int, int, gfp_t); int, int, gfp_t);
extern int bio_uncopy_user(struct bio *); extern int bio_uncopy_user(struct bio *);
void zero_fill_bio(struct bio *bio); void zero_fill_bio(struct bio *bio);

12
include/linux/blkdev.h
View File

@ -642,6 +642,12 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
} }
#endif /* CONFIG_MMU */ #endif /* CONFIG_MMU */
struct rq_map_data {
struct page **pages;
int page_order;
int nr_entries;
};
struct req_iterator { struct req_iterator {
int i; int i;
struct bio *bio; struct bio *bio;
@ -711,11 +717,13 @@ extern void __blk_run_queue(struct request_queue *);
extern void blk_run_queue(struct request_queue *); extern void blk_run_queue(struct request_queue *);
extern void blk_start_queueing(struct request_queue *); extern void blk_start_queueing(struct request_queue *);
extern int blk_rq_map_user(struct request_queue *, struct request *, extern int blk_rq_map_user(struct request_queue *, struct request *,
void __user *, unsigned long, gfp_t); struct rq_map_data *, void __user *, unsigned long,
gfp_t);
extern int blk_rq_unmap_user(struct bio *); extern int blk_rq_unmap_user(struct bio *);
extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
extern int blk_rq_map_user_iov(struct request_queue *, struct request *, extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
struct sg_iovec *, int, unsigned int, gfp_t); struct rq_map_data *, struct sg_iovec *, int,
unsigned int, gfp_t);
extern int blk_execute_rq(struct request_queue *, struct gendisk *, extern int blk_execute_rq(struct request_queue *, struct gendisk *,
struct request *, int); struct request *, int);
extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,