diff options
| -rw-r--r-- | block/blktrace.c | 24 | ||||
| -rw-r--r-- | block/compat_ioctl.c | 5 | ||||
| -rw-r--r-- | block/elevator.c | 26 | ||||
| -rw-r--r-- | block/ll_rw_blk.c | 49 | ||||
| -rw-r--r-- | drivers/scsi/sg.c | 12 | ||||
| -rw-r--r-- | fs/bio.c | 8 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 11 | ||||
| -rw-r--r-- | include/linux/blktrace_api.h | 12 |
8 files changed, 123 insertions, 24 deletions
diff --git a/block/blktrace.c b/block/blktrace.c index 9b4da4ae3c7d..568588cd16b2 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -235,7 +235,7 @@ static void blk_trace_cleanup(struct blk_trace *bt) kfree(bt); } -static int blk_trace_remove(struct request_queue *q) +int blk_trace_remove(struct request_queue *q) { struct blk_trace *bt; @@ -249,6 +249,7 @@ static int blk_trace_remove(struct request_queue *q) return 0; } +EXPORT_SYMBOL_GPL(blk_trace_remove); static int blk_dropped_open(struct inode *inode, struct file *filp) { @@ -316,18 +317,17 @@ static struct rchan_callbacks blk_relay_callbacks = { /* * Setup everything required to start tracing */ -int do_blk_trace_setup(struct request_queue *q, struct block_device *bdev, +int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, struct blk_user_trace_setup *buts) { struct blk_trace *old_bt, *bt = NULL; struct dentry *dir = NULL; - char b[BDEVNAME_SIZE]; int ret, i; if (!buts->buf_size || !buts->buf_nr) return -EINVAL; - strcpy(buts->name, bdevname(bdev, b)); + strcpy(buts->name, name); /* * some device names have larger paths - convert the slashes @@ -352,7 +352,7 @@ int do_blk_trace_setup(struct request_queue *q, struct block_device *bdev, goto err; bt->dir = dir; - bt->dev = bdev->bd_dev; + bt->dev = dev; atomic_set(&bt->dropped, 0); ret = -EIO; @@ -399,8 +399,8 @@ err: return ret; } -static int blk_trace_setup(struct request_queue *q, struct block_device *bdev, - char __user *arg) +int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, + char __user *arg) { struct blk_user_trace_setup buts; int ret; @@ -409,7 +409,7 @@ static int blk_trace_setup(struct request_queue *q, struct block_device *bdev, if (ret) return -EFAULT; - ret = do_blk_trace_setup(q, bdev, &buts); + ret = do_blk_trace_setup(q, name, dev, &buts); if (ret) return ret; @@ -418,8 +418,9 @@ static int blk_trace_setup(struct request_queue *q, struct block_device *bdev, return 0; } +EXPORT_SYMBOL_GPL(blk_trace_setup); -static int blk_trace_startstop(struct request_queue *q, int start) +int blk_trace_startstop(struct request_queue *q, int start) { struct blk_trace *bt; int ret; @@ -452,6 +453,7 @@ static int blk_trace_startstop(struct request_queue *q, int start) return ret; } +EXPORT_SYMBOL_GPL(blk_trace_startstop); /** * blk_trace_ioctl: - handle the ioctls associated with tracing @@ -464,6 +466,7 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) { struct request_queue *q; int ret, start = 0; + char b[BDEVNAME_SIZE]; q = bdev_get_queue(bdev); if (!q) @@ -473,7 +476,8 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) switch (cmd) { case BLKTRACESETUP: - ret = blk_trace_setup(q, bdev, arg); + strcpy(b, bdevname(bdev, b)); + ret = blk_trace_setup(q, b, bdev->bd_dev, arg); break; case BLKTRACESTART: start = 1; diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c index cae0a852619e..b73373216b0e 100644 --- a/block/compat_ioctl.c +++ b/block/compat_ioctl.c @@ -545,6 +545,7 @@ static int compat_blk_trace_setup(struct block_device *bdev, char __user *arg) struct blk_user_trace_setup buts; struct compat_blk_user_trace_setup cbuts; struct request_queue *q; + char b[BDEVNAME_SIZE]; int ret; q = bdev_get_queue(bdev); @@ -554,6 +555,8 @@ static int compat_blk_trace_setup(struct block_device *bdev, char __user *arg) if (copy_from_user(&cbuts, arg, sizeof(cbuts))) return -EFAULT; + strcpy(b, bdevname(bdev, b)); + buts = (struct blk_user_trace_setup) { .act_mask = cbuts.act_mask, .buf_size = cbuts.buf_size, @@ -565,7 +568,7 @@ static int compat_blk_trace_setup(struct block_device *bdev, char __user *arg) memcpy(&buts.name, &cbuts.name, 32); mutex_lock(&bdev->bd_mutex); - ret = do_blk_trace_setup(q, bdev, &buts); + ret = do_blk_trace_setup(q, b, bdev->bd_dev, &buts); mutex_unlock(&bdev->bd_mutex); if (ret) return ret; diff --git a/block/elevator.c b/block/elevator.c index f9736fbdab03..8cd5775acd7a 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -741,7 +741,21 @@ struct request *elv_next_request(struct request_queue *q) q->boundary_rq = NULL; } - if ((rq->cmd_flags & REQ_DONTPREP) || !q->prep_rq_fn) + if (rq->cmd_flags & REQ_DONTPREP) + break; + + if (q->dma_drain_size && rq->data_len) { + /* + * make sure space for the drain appears we + * know we can do this because max_hw_segments + * has been adjusted to be one fewer than the + * device can handle + */ + rq->nr_phys_segments++; + rq->nr_hw_segments++; + } + + if (!q->prep_rq_fn) break; ret = q->prep_rq_fn(q, rq); @@ -754,6 +768,16 @@ struct request *elv_next_request(struct request_queue *q) * avoid resource deadlock. REQ_STARTED will * prevent other fs requests from passing this one. */ + if (q->dma_drain_size && rq->data_len && + !(rq->cmd_flags & REQ_DONTPREP)) { + /* + * remove the space for the drain we added + * so that we don't add it again + */ + --rq->nr_phys_segments; + --rq->nr_hw_segments; + } + rq = NULL; break; } else if (ret == BLKPREP_KILL) { diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index c16fdfed8c62..1932a56f5e4b 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -721,6 +721,45 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b) EXPORT_SYMBOL(blk_queue_stack_limits); /** + * blk_queue_dma_drain - Set up a drain buffer for excess dma. + * + * @q: the request queue for the device + * @buf: physically contiguous buffer + * @size: size of the buffer in bytes + * + * Some devices have excess DMA problems and can't simply discard (or + * zero fill) the unwanted piece of the transfer. They have to have a + * real area of memory to transfer it into. The use case for this is + * ATAPI devices in DMA mode. If the packet command causes a transfer + * bigger than the transfer size some HBAs will lock up if there + * aren't DMA elements to contain the excess transfer. What this API + * does is adjust the queue so that the buf is always appended + * silently to the scatterlist. + * + * Note: This routine adjusts max_hw_segments to make room for + * appending the drain buffer. If you call + * blk_queue_max_hw_segments() or blk_queue_max_phys_segments() after + * calling this routine, you must set the limit to one fewer than your + * device can support otherwise there won't be room for the drain + * buffer. + */ +int blk_queue_dma_drain(struct request_queue *q, void *buf, + unsigned int size) +{ + if (q->max_hw_segments < 2 || q->max_phys_segments < 2) + return -EINVAL; + /* make room for appending the drain */ + --q->max_hw_segments; + --q->max_phys_segments; + q->dma_drain_buffer = buf; + q->dma_drain_size = size; + + return 0; +} + +EXPORT_SYMBOL_GPL(blk_queue_dma_drain); + +/** * blk_queue_segment_boundary - set boundary rules for segment merging * @q: the request queue for the device * @mask: the memory boundary mask @@ -1374,6 +1413,16 @@ new_segment: bvprv = bvec; } /* segments in rq */ + if (q->dma_drain_size) { + sg->page_link &= ~0x02; + sg = sg_next(sg); + sg_set_page(sg, virt_to_page(q->dma_drain_buffer), + q->dma_drain_size, + ((unsigned long)q->dma_drain_buffer) & + (PAGE_SIZE - 1)); + nsegs++; + } + if (sg) sg_mark_end(sg); diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 17216b76efdc..aba28f335b88 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -48,6 +48,7 @@ static int sg_version_num = 30534; /* 2 digits for each component */ #include <linux/blkdev.h> #include <linux/delay.h> #include <linux/scatterlist.h> +#include <linux/blktrace_api.h> #include "scsi.h" #include <scsi/scsi_dbg.h> @@ -1067,6 +1068,17 @@ sg_ioctl(struct inode *inode, struct file *filp, case BLKSECTGET: return put_user(sdp->device->request_queue->max_sectors * 512, ip); + case BLKTRACESETUP: + return blk_trace_setup(sdp->device->request_queue, + sdp->disk->disk_name, + sdp->device->sdev_gendev.devt, + (char *)arg); + case BLKTRACESTART: + return blk_trace_startstop(sdp->device->request_queue, 1); + case BLKTRACESTOP: + return blk_trace_startstop(sdp->device->request_queue, 0); + case BLKTRACETEARDOWN: + return blk_trace_remove(sdp->device->request_queue); default: if (read_only) return -EPERM; /* don't know so take safe approach */ @@ -248,11 +248,13 @@ inline int bio_hw_segments(struct request_queue *q, struct bio *bio) */ void __bio_clone(struct bio *bio, struct bio *bio_src) { - struct request_queue *q = bdev_get_queue(bio_src->bi_bdev); - memcpy(bio->bi_io_vec, bio_src->bi_io_vec, bio_src->bi_max_vecs * sizeof(struct bio_vec)); + /* + * most users will be overriding ->bi_bdev with a new target, + * so we don't set nor calculate new physical/hw segment counts here + */ bio->bi_sector = bio_src->bi_sector; bio->bi_bdev = bio_src->bi_bdev; bio->bi_flags |= 1 << BIO_CLONED; @@ -260,8 +262,6 @@ void __bio_clone(struct bio *bio, struct bio *bio_src) bio->bi_vcnt = bio_src->bi_vcnt; bio->bi_size = bio_src->bi_size; bio->bi_idx = bio_src->bi_idx; - bio_phys_segments(q, bio); - bio_hw_segments(q, bio); } /** diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index b71c3900810d..71e7a847dffc 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -356,6 +356,8 @@ struct request_queue unsigned int max_segment_size; unsigned long seg_boundary_mask; + void *dma_drain_buffer; + unsigned int dma_drain_size; unsigned int dma_alignment; struct blk_queue_tag *queue_tags; @@ -692,6 +694,8 @@ extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short); extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); extern void blk_queue_hardsect_size(struct request_queue *, unsigned short); extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); +extern int blk_queue_dma_drain(struct request_queue *q, void *buf, + unsigned int size); extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); @@ -768,12 +772,7 @@ static inline int bdev_hardsect_size(struct block_device *bdev) static inline int queue_dma_alignment(struct request_queue *q) { - int retval = 511; - - if (q && q->dma_alignment) - retval = q->dma_alignment; - - return retval; + return q ? q->dma_alignment : 511; } /* assumes size > 256 */ diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 7e11d23ac36a..06dadba349ac 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -148,7 +148,7 @@ extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); extern void blk_trace_shutdown(struct request_queue *); extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); extern int do_blk_trace_setup(struct request_queue *q, - struct block_device *bdev, struct blk_user_trace_setup *buts); + char *name, dev_t dev, struct blk_user_trace_setup *buts); /** @@ -282,6 +282,11 @@ static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); } +extern int blk_trace_setup(request_queue_t *q, char *name, dev_t dev, + char __user *arg); +extern int blk_trace_startstop(request_queue_t *q, int start); +extern int blk_trace_remove(request_queue_t *q); + #else /* !CONFIG_BLK_DEV_IO_TRACE */ #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) #define blk_trace_shutdown(q) do { } while (0) @@ -290,7 +295,10 @@ static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) -#define do_blk_trace_setup(q, bdev, buts) (-ENOTTY) +#define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY) +#define blk_trace_setup(q, name, dev, arg) (-ENOTTY) +#define blk_trace_startstop(q, start) (-ENOTTY) +#define blk_trace_remove(q) (-ENOTTY) #endif /* CONFIG_BLK_DEV_IO_TRACE */ #endif /* __KERNEL__ */ #endif |