[PATCH 2/2] block: convert bsg, scsi_ioctl and cdrom to newblk_rq_map_user fns
From: Mike Christie
Date: Sat Sep 09 2006 - 17:50:54 EST
This patch just converts bsg, scsi_ioctl and cdrom to
the new functions. There is not really much of a change
for scsi_ioctl and cdrom. The block layer functions
handle things like bounce buffers, and bio unmapping accounting
for them now.
The bsg change is larger since I based the blk layer functions
on it and the scsi lib code, so there are lots of deletions.
There were also a couple of bugs that got fixes as a result
of using the blk layer API:
- If the hdr iovec_count = 0, then the request was not getting
freed because blk_unmap_sghdr_rq thought blk_rq_unmap_user
would free the request which it does not.
- blk_unmap_sghdr_rq would always call bio_unmap_user, even if
bio_copy_user was used. This was causing all types of weird bugs
like slab corruption.
I have tested the copy and map code with scsi_ioctl.c with large
requests having multiple bios. I have not tested bsg or cdrom.
And High Mem is not tested well. I am not sure how to force high
mem pages to be used for the mapping. Was there a proc or module
param that can be used?
Patch was made over Jens's block tree and the bsg branch
Signed-off-by: Mike Christie <michaelc@xxxxxxxxxxx>
---
block/bsg.c | 80 +++++++------------------------------------------
block/scsi_ioctl.c | 38 ++++++++---------------
drivers/cdrom/cdrom.c | 7 +---
3 files changed, 26 insertions(+), 99 deletions(-)
diff --git a/block/bsg.c b/block/bsg.c
index cf48a81..41e8140 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -70,11 +70,6 @@ #define BSG_CMDS_MASK (BSG_CMDS_PER_LON
#define BSG_CMDS_BYTES (PAGE_SIZE * (1 << BSG_CMDS_PAGE_ORDER))
#define BSG_CMDS (BSG_CMDS_BYTES / sizeof(struct bsg_command))
-/*
- * arbitrary limit, mapping bio's will reveal true device limit
- */
-#define BSG_MAX_VECS (128)
-
#undef BSG_DEBUG
#ifdef BSG_DEBUG
@@ -107,7 +102,6 @@ struct bsg_command {
struct bsg_device *bd;
struct list_head list;
struct request *rq;
- struct bio *bio;
int err;
struct sg_io_hdr hdr;
struct sg_io_hdr __user *uhdr;
@@ -251,8 +245,6 @@ bsg_validate_sghdr(request_queue_t *q, s
return -EINVAL;
if (hdr->cmd_len > BLK_MAX_CDB)
return -EINVAL;
- if (hdr->iovec_count > BSG_MAX_VECS)
- return -EINVAL;
if (hdr->dxfer_len > (q->max_sectors << 9))
return -EIO;
@@ -301,6 +293,12 @@ bsg_map_hdr(request_queue_t *q, int rw,
* map scatter-gather elements seperately and string them to request
*/
rq = blk_get_request(q, rw, GFP_KERNEL);
+ ret = blk_fill_sghdr_rq(q, rq, &bc->hdr, test_bit(BSG_F_WRITE_PERM,
+ &bd->flags));
+ if (ret) {
+ blk_put_request(rq);
+ return ERR_PTR(ret);
+ }
if (!hdr->iovec_count) {
ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len);
@@ -310,7 +308,6 @@ bsg_map_hdr(request_queue_t *q, int rw,
u_iov = hdr->dxferp;
for (ret = 0, i = 0; i < hdr->iovec_count; i++, u_iov++) {
- int to_vm = rw == READ;
unsigned long uaddr;
if (copy_from_user(&iov, u_iov, sizeof(iov))) {
@@ -323,57 +320,9 @@ bsg_map_hdr(request_queue_t *q, int rw,
break;
}
- uaddr = (unsigned long) iov.iov_base;
- if (!(uaddr & queue_dma_alignment(q))
- && !(iov.iov_len & queue_dma_alignment(q)))
- bio = bio_map_user(q, NULL, uaddr, iov.iov_len, to_vm);
- else
- bio = bio_copy_user(q, uaddr, iov.iov_len, to_vm);
-
- if (IS_ERR(bio)) {
- ret = PTR_ERR(bio);
- bio = NULL;
+ ret = blk_rq_map_user(q, rq, uaddr, iov.iov_len);
+ if (ret)
break;
- }
-
- dprintk("bsg: adding segment %d\n", i);
-
- if (rq->bio) {
- /*
- * for most (all? don't know of any) queues we could
- * skip grabbing the queue lock here. only drivers with
- * funky private ->back_merge_fn() function could be
- * problematic.
- */
- spin_lock_irq(q->queue_lock);
- ret = q->back_merge_fn(q, rq, bio);
- spin_unlock_irq(q->queue_lock);
-
- rq->biotail->bi_next = bio;
- rq->biotail = bio;
-
- /*
- * break after adding bio, so we don't have to special
- * case the cleanup too much
- */
- if (!ret) {
- ret = -EINVAL;
- break;
- }
-
- /*
- * merged ok, update state
- */
- rq->nr_sectors += bio_sectors(bio);
- rq->hard_nr_sectors = rq->nr_sectors;
- rq->data_len += bio->bi_size;
- } else {
- /*
- * first bio, setup rq state
- */
- blk_rq_bio_prep(q, rq, bio);
- }
- ret = 0;
}
/*
@@ -399,8 +348,8 @@ static void bsg_rq_end_io(struct request
struct bsg_device *bd = bc->bd;
unsigned long flags;
- dprintk("%s: finished rq %p bio %p, bc %p offset %ld stat %d\n",
- bd->name, rq, bc, bc->bio, bc - bd->cmd_map, uptodate);
+ dprintk("%s: finished rq %p, bc %p offset %ld stat %d\n",
+ bd->name, rq, bc, bc - bd->cmd_map, uptodate);
bc->hdr.duration = jiffies_to_msecs(jiffies - bc->hdr.duration);
@@ -424,7 +373,6 @@ static void bsg_add_command(struct bsg_d
* add bc command to busy queue and submit rq for io
*/
bc->rq = rq;
- bc->bio = rq->bio;
bc->hdr.duration = jiffies;
spin_lock_irq(&bd->lock);
list_add_tail(&bc->list, &bd->busy_list);
@@ -529,7 +477,7 @@ static int bsg_complete_all_commands(str
break;
}
- tret = blk_complete_sghdr_rq(bc->rq, &bc->hdr, bc->bio);
+ tret = blk_complete_sghdr_rq(bc->rq, &bc->hdr);
if (!ret)
ret = tret;
@@ -565,7 +513,7 @@ __bsg_read(char __user *buf, size_t coun
* after completing the request. so do that here,
* bsg_complete_work() cannot do that for us
*/
- ret = blk_complete_sghdr_rq(bc->rq, &bc->hdr, bc->bio);
+ ret = blk_complete_sghdr_rq(bc->rq, &bc->hdr);
if (copy_to_user(buf, (char *) &bc->hdr, sizeof(bc->hdr)))
ret = -EFAULT;
@@ -774,10 +722,6 @@ static ssize_t __bsg_write(struct bsg_de
break;
}
- ret = blk_fill_sghdr_rq(q, rq, &bc->hdr, test_bit(BSG_F_WRITE_PERM, &bd->flags));
- if (ret)
- break;
-
bsg_add_command(bd, q, bc, rq);
bc = NULL;
rq = NULL;
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 9426b54..afd4630 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -246,24 +246,16 @@ EXPORT_SYMBOL_GPL(blk_fill_sghdr_rq);
*/
int blk_unmap_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr)
{
- struct bio *bio = rq->bio;
-
/*
* also releases request
*/
- if (!hdr->iovec_count)
- return blk_rq_unmap_user(bio, hdr->dxfer_len);
-
- rq_for_each_bio(bio, rq)
- bio_unmap_user(bio);
-
+ blk_rq_unmap_user(rq);
blk_put_request(rq);
return 0;
}
EXPORT_SYMBOL_GPL(blk_unmap_sghdr_rq);
-int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
- struct bio *bio)
+int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr)
{
int r, ret = 0;
@@ -290,7 +282,6 @@ int blk_complete_sghdr_rq(struct request
ret = -EFAULT;
}
- rq->bio = bio;
r = blk_unmap_sghdr_rq(rq, hdr);
if (ret)
r = ret;
@@ -305,7 +296,6 @@ static int sg_io(struct file *file, requ
unsigned long start_time;
int writing = 0, ret = 0, has_write_perm = 0;
struct request *rq;
- struct bio *bio;
char sense[SCSI_SENSE_BUFFERSIZE];
if (hdr->interface_id != 'S')
@@ -332,6 +322,14 @@ static int sg_io(struct file *file, requ
if (!rq)
return -ENOMEM;
+ if (file)
+ has_write_perm = file->f_mode & FMODE_WRITE;
+
+ if (blk_fill_sghdr_rq(q, rq, hdr, has_write_perm)) {
+ blk_put_request(rq);
+ return -EFAULT;
+ }
+
if (hdr->iovec_count) {
const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
struct sg_iovec *iov;
@@ -348,7 +346,8 @@ static int sg_io(struct file *file, requ
goto out;
}
- ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count);
+ ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count,
+ hdr->dxfer_len);
kfree(iov);
} else if (hdr->dxfer_len)
ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len);
@@ -356,17 +355,6 @@ static int sg_io(struct file *file, requ
if (ret)
goto out;
- if (file)
- has_write_perm = file->f_mode & FMODE_WRITE;
-
- bio = rq->bio;
-
- if (blk_fill_sghdr_rq(q, rq, hdr, has_write_perm)) {
- blk_rq_unmap_user(bio, hdr->dxfer_len);
- blk_put_request(rq);
- return -EFAULT;
- }
-
memset(sense, 0, sizeof(sense));
rq->sense = sense;
rq->sense_len = 0;
@@ -383,7 +371,7 @@ static int sg_io(struct file *file, requ
hdr->duration = ((jiffies - start_time) * 1000) / HZ;
- return blk_complete_sghdr_rq(rq, hdr, bio);
+ return blk_complete_sghdr_rq(rq, hdr);
out:
blk_put_request(rq);
return ret;
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index b38c84a..5991263 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2090,7 +2090,6 @@ static int cdrom_read_cdda_bpc(struct cd
{
request_queue_t *q = cdi->disk->queue;
struct request *rq;
- struct bio *bio;
unsigned int len;
int nr, ret = 0;
@@ -2131,10 +2130,6 @@ static int cdrom_read_cdda_bpc(struct cd
rq->cmd_len = 12;
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->timeout = 60 * HZ;
- bio = rq->bio;
-
- if (rq->bio)
- blk_queue_bounce(q, &rq->bio);
if (blk_execute_rq(q, cdi->disk, rq, 0)) {
struct request_sense *s = rq->sense;
@@ -2142,7 +2137,7 @@ static int cdrom_read_cdda_bpc(struct cd
cdi->last_sense = s->sense_key;
}
- if (blk_rq_unmap_user(bio, len))
+ if (blk_rq_unmap_user(rq))
ret = -EFAULT;
if (ret)
--
1.4.1
-
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