diff options
author | Tejun Heo <tj@kernel.org> | 2010-09-03 13:56:16 +0400 |
---|---|---|
committer | Jens Axboe <jaxboe@fusionio.com> | 2010-09-10 14:35:36 +0400 |
commit | 4913efe456c987057e5d36a3f0a55422a9072cae (patch) | |
tree | 295f04a7214e1933df3301dd42c12ff3f282a22c | |
parent | 6958f145459ca7ad9715024de97445addacb8510 (diff) | |
download | linux-4913efe456c987057e5d36a3f0a55422a9072cae.tar.xz |
block: deprecate barrier and replace blk_queue_ordered() with blk_queue_flush()
Barrier is deemed too heavy and will soon be replaced by FLUSH/FUA
requests. Deprecate barrier. All REQ_HARDBARRIERs are failed with
-EOPNOTSUPP and blk_queue_ordered() is replaced with simpler
blk_queue_flush().
blk_queue_flush() takes combinations of REQ_FLUSH and FUA. If a
device has write cache and can flush it, it should set REQ_FLUSH. If
the device can handle FUA writes, it should also set REQ_FUA.
All blk_queue_ordered() users are converted.
* ORDERED_DRAIN is mapped to 0 which is the default value.
* ORDERED_DRAIN_FLUSH is mapped to REQ_FLUSH.
* ORDERED_DRAIN_FLUSH_FUA is mapped to REQ_FLUSH | REQ_FUA.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
-rw-r--r-- | block/blk-barrier.c | 29 | ||||
-rw-r--r-- | block/blk-core.c | 6 | ||||
-rw-r--r-- | block/blk-settings.c | 20 | ||||
-rw-r--r-- | drivers/block/brd.c | 1 | ||||
-rw-r--r-- | drivers/block/loop.c | 2 | ||||
-rw-r--r-- | drivers/block/osdblk.c | 2 | ||||
-rw-r--r-- | drivers/block/ps3disk.c | 2 | ||||
-rw-r--r-- | drivers/block/virtio_blk.c | 25 | ||||
-rw-r--r-- | drivers/block/xen-blkfront.c | 43 | ||||
-rw-r--r-- | drivers/ide/ide-disk.c | 13 | ||||
-rw-r--r-- | drivers/md/dm.c | 2 | ||||
-rw-r--r-- | drivers/mmc/card/queue.c | 1 | ||||
-rw-r--r-- | drivers/s390/block/dasd.c | 1 | ||||
-rw-r--r-- | drivers/scsi/sd.c | 16 | ||||
-rw-r--r-- | include/linux/blkdev.h | 6 |
15 files changed, 67 insertions, 102 deletions
diff --git a/block/blk-barrier.c b/block/blk-barrier.c index c807e9ca3a68..ed0aba5463ab 100644 --- a/block/blk-barrier.c +++ b/block/blk-barrier.c @@ -9,35 +9,6 @@ #include "blk.h" -/** - * blk_queue_ordered - does this queue support ordered writes - * @q: the request queue - * @ordered: one of QUEUE_ORDERED_* - * - * Description: - * For journalled file systems, doing ordered writes on a commit - * block instead of explicitly doing wait_on_buffer (which is bad - * for performance) can be a big win. Block drivers supporting this - * feature should call this function and indicate so. - * - **/ -int blk_queue_ordered(struct request_queue *q, unsigned ordered) -{ - if (ordered != QUEUE_ORDERED_NONE && - ordered != QUEUE_ORDERED_DRAIN && - ordered != QUEUE_ORDERED_DRAIN_FLUSH && - ordered != QUEUE_ORDERED_DRAIN_FUA) { - printk(KERN_ERR "blk_queue_ordered: bad value %d\n", ordered); - return -EINVAL; - } - - q->ordered = ordered; - q->next_ordered = ordered; - - return 0; -} -EXPORT_SYMBOL(blk_queue_ordered); - /* * Cache flushing for ordered writes handling */ diff --git a/block/blk-core.c b/block/blk-core.c index ee1a1e7e63cc..f06354183b29 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1203,11 +1203,13 @@ static int __make_request(struct request_queue *q, struct bio *bio) const unsigned int ff = bio->bi_rw & REQ_FAILFAST_MASK; int rw_flags; - if ((bio->bi_rw & REQ_HARDBARRIER) && - (q->next_ordered == QUEUE_ORDERED_NONE)) { + /* REQ_HARDBARRIER is no more */ + if (WARN_ONCE(bio->bi_rw & REQ_HARDBARRIER, + "block: HARDBARRIER is deprecated, use FLUSH/FUA instead\n")) { bio_endio(bio, -EOPNOTSUPP); return 0; } + /* * low level driver can indicate that it wants pages above a * certain limit bounced to low memory (ie for highmem, or even diff --git a/block/blk-settings.c b/block/blk-settings.c index a234f4bf1d6f..9b18afcfe925 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -794,6 +794,26 @@ void blk_queue_update_dma_alignment(struct request_queue *q, int mask) } EXPORT_SYMBOL(blk_queue_update_dma_alignment); +/** + * blk_queue_flush - configure queue's cache flush capability + * @q: the request queue for the device + * @flush: 0, REQ_FLUSH or REQ_FLUSH | REQ_FUA + * + * Tell block layer cache flush capability of @q. If it supports + * flushing, REQ_FLUSH should be set. If it supports bypassing + * write cache for individual writes, REQ_FUA should be set. + */ +void blk_queue_flush(struct request_queue *q, unsigned int flush) +{ + WARN_ON_ONCE(flush & ~(REQ_FLUSH | REQ_FUA)); + + if (WARN_ON_ONCE(!(flush & REQ_FLUSH) && (flush & REQ_FUA))) + flush &= ~REQ_FUA; + + q->flush_flags = flush & (REQ_FLUSH | REQ_FUA); +} +EXPORT_SYMBOL_GPL(blk_queue_flush); + static int __init blk_settings_init(void) { blk_max_low_pfn = max_low_pfn - 1; diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 47a41272d26b..fa33f97722ba 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -482,7 +482,6 @@ static struct brd_device *brd_alloc(int i) if (!brd->brd_queue) goto out_free_dev; blk_queue_make_request(brd->brd_queue, brd_make_request); - blk_queue_ordered(brd->brd_queue, QUEUE_ORDERED_DRAIN); blk_queue_max_hw_sectors(brd->brd_queue, 1024); blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY); diff --git a/drivers/block/loop.c b/drivers/block/loop.c index c3a4a2e176da..953d1e12f4d4 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -832,7 +832,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, lo->lo_queue->unplug_fn = loop_unplug; if (!(lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync) - blk_queue_ordered(lo->lo_queue, QUEUE_ORDERED_DRAIN_FLUSH); + blk_queue_flush(lo->lo_queue, REQ_FLUSH); set_capacity(lo->lo_disk, size); bd_set_size(bdev, size << 9); diff --git a/drivers/block/osdblk.c b/drivers/block/osdblk.c index 2284b4f05c62..72d62462433d 100644 --- a/drivers/block/osdblk.c +++ b/drivers/block/osdblk.c @@ -439,7 +439,7 @@ static int osdblk_init_disk(struct osdblk_device *osdev) blk_queue_stack_limits(q, osd_request_queue(osdev->osd)); blk_queue_prep_rq(q, blk_queue_start_tag); - blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH); + blk_queue_flush(q, REQ_FLUSH); disk->queue = q; diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c index e9da874d0419..4911f9e57bc7 100644 --- a/drivers/block/ps3disk.c +++ b/drivers/block/ps3disk.c @@ -468,7 +468,7 @@ static int __devinit ps3disk_probe(struct ps3_system_bus_device *_dev) blk_queue_dma_alignment(queue, dev->blk_size-1); blk_queue_logical_block_size(queue, dev->blk_size); - blk_queue_ordered(queue, QUEUE_ORDERED_DRAIN_FLUSH); + blk_queue_flush(queue, REQ_FLUSH); blk_queue_max_segments(queue, -1); blk_queue_max_segment_size(queue, dev->bounce_size); diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 79652809eee8..d10b635b3946 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -388,22 +388,15 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) vblk->disk->driverfs_dev = &vdev->dev; index++; - if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH)) { - /* - * If the FLUSH feature is supported we do have support for - * flushing a volatile write cache on the host. Use that - * to implement write barrier support. - */ - blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH); - } else { - /* - * If the FLUSH feature is not supported we must assume that - * the host does not perform any kind of volatile write - * caching. We still need to drain the queue to provider - * proper barrier semantics. - */ - blk_queue_ordered(q, QUEUE_ORDERED_DRAIN); - } + /* + * If the FLUSH feature is supported we do have support for + * flushing a volatile write cache on the host. Use that to + * implement write barrier support; otherwise, we must assume + * that the host does not perform any kind of volatile write + * caching. + */ + if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH)) + blk_queue_flush(q, REQ_FLUSH); /* If disk is read-only in the host, the guest should obey */ if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO)) diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 50ec6f834996..0b1eea643262 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -95,7 +95,7 @@ struct blkfront_info struct gnttab_free_callback callback; struct blk_shadow shadow[BLK_RING_SIZE]; unsigned long shadow_free; - int feature_barrier; + unsigned int feature_flush; int is_ready; }; @@ -418,25 +418,12 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size) } -static int xlvbd_barrier(struct blkfront_info *info) +static void xlvbd_flush(struct blkfront_info *info) { - int err; - const char *barrier; - - switch (info->feature_barrier) { - case QUEUE_ORDERED_DRAIN: barrier = "enabled"; break; - case QUEUE_ORDERED_NONE: barrier = "disabled"; break; - default: return -EINVAL; - } - - err = blk_queue_ordered(info->rq, info->feature_barrier); - - if (err) - return err; - + blk_queue_flush(info->rq, info->feature_flush); printk(KERN_INFO "blkfront: %s: barriers %s\n", - info->gd->disk_name, barrier); - return 0; + info->gd->disk_name, + info->feature_flush ? "enabled" : "disabled"); } @@ -515,7 +502,7 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, info->rq = gd->queue; info->gd = gd; - xlvbd_barrier(info); + xlvbd_flush(info); if (vdisk_info & VDISK_READONLY) set_disk_ro(gd, 1); @@ -661,8 +648,8 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id) printk(KERN_WARNING "blkfront: %s: write barrier op failed\n", info->gd->disk_name); error = -EOPNOTSUPP; - info->feature_barrier = QUEUE_ORDERED_NONE; - xlvbd_barrier(info); + info->feature_flush = 0; + xlvbd_flush(info); } /* fall through */ case BLKIF_OP_READ: @@ -1075,19 +1062,13 @@ static void blkfront_connect(struct blkfront_info *info) /* * If there's no "feature-barrier" defined, then it means * we're dealing with a very old backend which writes - * synchronously; draining will do what needs to get done. + * synchronously; nothing to do. * * If there are barriers, then we use flush. - * - * If barriers are not supported, then there's no much we can - * do, so just set ordering to NONE. */ - if (err) - info->feature_barrier = QUEUE_ORDERED_DRAIN; - else if (barrier) - info->feature_barrier = QUEUE_ORDERED_DRAIN_FLUSH; - else - info->feature_barrier = QUEUE_ORDERED_NONE; + info->feature_flush = 0; + if (!err && barrier) + info->feature_flush = REQ_FLUSH; err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size); if (err) { diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c index 7433e07de30e..7c5b01ce51d2 100644 --- a/drivers/ide/ide-disk.c +++ b/drivers/ide/ide-disk.c @@ -516,10 +516,10 @@ static int ide_do_setfeature(ide_drive_t *drive, u8 feature, u8 nsect) return ide_no_data_taskfile(drive, &cmd); } -static void update_ordered(ide_drive_t *drive) +static void update_flush(ide_drive_t *drive) { u16 *id = drive->id; - unsigned ordered = QUEUE_ORDERED_NONE; + unsigned flush = 0; if (drive->dev_flags & IDE_DFLAG_WCACHE) { unsigned long long capacity; @@ -543,13 +543,12 @@ static void update_ordered(ide_drive_t *drive) drive->name, barrier ? "" : "not "); if (barrier) { - ordered = QUEUE_ORDERED_DRAIN_FLUSH; + flush = REQ_FLUSH; blk_queue_prep_rq(drive->queue, idedisk_prep_fn); } - } else - ordered = QUEUE_ORDERED_DRAIN; + } - blk_queue_ordered(drive->queue, ordered); + blk_queue_flush(drive->queue, flush); } ide_devset_get_flag(wcache, IDE_DFLAG_WCACHE); @@ -572,7 +571,7 @@ static int set_wcache(ide_drive_t *drive, int arg) } } - update_ordered(drive); + update_flush(drive); return err; } diff --git a/drivers/md/dm.c b/drivers/md/dm.c index ac384b2a6a33..b1d92be8f990 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -2245,7 +2245,7 @@ static int dm_init_request_based_queue(struct mapped_device *md) blk_queue_softirq_done(md->queue, dm_softirq_done); blk_queue_prep_rq(md->queue, dm_prep_fn); blk_queue_lld_busy(md->queue, dm_lld_busy); - blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN_FLUSH); + blk_queue_flush(md->queue, REQ_FLUSH); elv_register_queue(md->queue); diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c index e876678176be..9c0b42bfe089 100644 --- a/drivers/mmc/card/queue.c +++ b/drivers/mmc/card/queue.c @@ -128,7 +128,6 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock mq->req = NULL; blk_queue_prep_rq(mq->queue, mmc_prep_request); - blk_queue_ordered(mq->queue, QUEUE_ORDERED_DRAIN); queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue); if (mmc_can_erase(card)) { queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mq->queue); diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 8373ca0de8e0..9b106d83b0cd 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -2197,7 +2197,6 @@ static void dasd_setup_queue(struct dasd_block *block) */ blk_queue_max_segment_size(block->request_queue, PAGE_SIZE); blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1); - blk_queue_ordered(block->request_queue, QUEUE_ORDERED_DRAIN); } /* diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index cdfc51ab9cf2..63bd01ae534f 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2109,7 +2109,7 @@ static int sd_revalidate_disk(struct gendisk *disk) struct scsi_disk *sdkp = scsi_disk(disk); struct scsi_device *sdp = sdkp->device; unsigned char *buffer; - unsigned ordered; + unsigned flush = 0; SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_revalidate_disk\n")); @@ -2151,15 +2151,15 @@ static int sd_revalidate_disk(struct gendisk *disk) /* * We now have all cache related info, determine how we deal - * with ordered requests. + * with flush requests. */ - if (sdkp->WCE) - ordered = sdkp->DPOFUA - ? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH; - else - ordered = QUEUE_ORDERED_DRAIN; + if (sdkp->WCE) { + flush |= REQ_FLUSH; + if (sdkp->DPOFUA) + flush |= REQ_FUA; + } - blk_queue_ordered(sdkp->disk->queue, ordered); + blk_queue_flush(sdkp->disk->queue, flush); set_capacity(disk, sdkp->capacity); kfree(buffer); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 7077bc0d6138..e97911d4dec3 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -355,8 +355,10 @@ struct request_queue struct blk_trace *blk_trace; #endif /* - * reserved for flush operations + * for flush operations */ + unsigned int flush_flags; + unsigned int ordered, next_ordered, ordseq; int orderr, ordcolor; struct request pre_flush_rq, bar_rq, post_flush_rq; @@ -865,8 +867,8 @@ extern void blk_queue_update_dma_alignment(struct request_queue *, int); extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); +extern void blk_queue_flush(struct request_queue *q, unsigned int flush); extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); -extern int blk_queue_ordered(struct request_queue *, unsigned); extern bool blk_do_ordered(struct request_queue *, struct request **); extern unsigned blk_ordered_cur_seq(struct request_queue *); extern unsigned blk_ordered_req_seq(struct request *); |