mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
Merge branch 'stable/for-jens-3.2' of git://oss.oracle.com/git/kwilk/xen into for-3.2/drivers
This commit is contained in:
commit
b8d8bdfe31
5 changed files with 402 additions and 65 deletions
|
@ -39,6 +39,9 @@
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|||
#include <linux/list.h>
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#include <linux/delay.h>
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#include <linux/freezer.h>
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#include <linux/loop.h>
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#include <linux/falloc.h>
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#include <linux/fs.h>
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#include <xen/events.h>
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#include <xen/page.h>
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|
@ -258,13 +261,16 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
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static void print_stats(struct xen_blkif *blkif)
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{
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pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d\n",
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pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d"
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" | ds %4d\n",
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current->comm, blkif->st_oo_req,
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blkif->st_rd_req, blkif->st_wr_req, blkif->st_f_req);
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blkif->st_rd_req, blkif->st_wr_req,
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blkif->st_f_req, blkif->st_ds_req);
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blkif->st_print = jiffies + msecs_to_jiffies(10 * 1000);
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blkif->st_rd_req = 0;
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blkif->st_wr_req = 0;
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blkif->st_oo_req = 0;
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blkif->st_ds_req = 0;
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}
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int xen_blkif_schedule(void *arg)
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@ -410,6 +416,59 @@ static int xen_blkbk_map(struct blkif_request *req,
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return ret;
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}
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static void xen_blk_discard(struct xen_blkif *blkif, struct blkif_request *req)
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{
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int err = 0;
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int status = BLKIF_RSP_OKAY;
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struct block_device *bdev = blkif->vbd.bdev;
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if (blkif->blk_backend_type == BLKIF_BACKEND_PHY)
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/* just forward the discard request */
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err = blkdev_issue_discard(bdev,
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req->u.discard.sector_number,
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req->u.discard.nr_sectors,
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GFP_KERNEL, 0);
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else if (blkif->blk_backend_type == BLKIF_BACKEND_FILE) {
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/* punch a hole in the backing file */
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struct loop_device *lo = bdev->bd_disk->private_data;
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struct file *file = lo->lo_backing_file;
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if (file->f_op->fallocate)
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err = file->f_op->fallocate(file,
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FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
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req->u.discard.sector_number << 9,
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req->u.discard.nr_sectors << 9);
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else
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err = -EOPNOTSUPP;
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} else
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err = -EOPNOTSUPP;
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if (err == -EOPNOTSUPP) {
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pr_debug(DRV_PFX "discard op failed, not supported\n");
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status = BLKIF_RSP_EOPNOTSUPP;
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} else if (err)
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status = BLKIF_RSP_ERROR;
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make_response(blkif, req->id, req->operation, status);
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}
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static void xen_blk_drain_io(struct xen_blkif *blkif)
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{
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atomic_set(&blkif->drain, 1);
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do {
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/* The initial value is one, and one refcnt taken at the
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* start of the xen_blkif_schedule thread. */
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if (atomic_read(&blkif->refcnt) <= 2)
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break;
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wait_for_completion_interruptible_timeout(
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&blkif->drain_complete, HZ);
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if (!atomic_read(&blkif->drain))
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break;
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} while (!kthread_should_stop());
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atomic_set(&blkif->drain, 0);
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}
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/*
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* Completion callback on the bio's. Called as bh->b_end_io()
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*/
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@ -422,6 +481,11 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
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pr_debug(DRV_PFX "flush diskcache op failed, not supported\n");
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xen_blkbk_flush_diskcache(XBT_NIL, pending_req->blkif->be, 0);
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pending_req->status = BLKIF_RSP_EOPNOTSUPP;
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} else if ((pending_req->operation == BLKIF_OP_WRITE_BARRIER) &&
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(error == -EOPNOTSUPP)) {
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pr_debug(DRV_PFX "write barrier op failed, not supported\n");
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xen_blkbk_barrier(XBT_NIL, pending_req->blkif->be, 0);
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pending_req->status = BLKIF_RSP_EOPNOTSUPP;
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} else if (error) {
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pr_debug(DRV_PFX "Buffer not up-to-date at end of operation,"
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" error=%d\n", error);
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@ -438,6 +502,10 @@ static void __end_block_io_op(struct pending_req *pending_req, int error)
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make_response(pending_req->blkif, pending_req->id,
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pending_req->operation, pending_req->status);
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xen_blkif_put(pending_req->blkif);
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if (atomic_read(&pending_req->blkif->refcnt) <= 2) {
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if (atomic_read(&pending_req->blkif->drain))
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complete(&pending_req->blkif->drain_complete);
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}
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free_req(pending_req);
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}
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}
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@ -532,7 +600,6 @@ do_block_io_op(struct xen_blkif *blkif)
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return more_to_do;
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}
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/*
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* Transmutation of the 'struct blkif_request' to a proper 'struct bio'
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* and call the 'submit_bio' to pass it to the underlying storage.
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@ -549,6 +616,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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int i, nbio = 0;
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int operation;
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struct blk_plug plug;
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bool drain = false;
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switch (req->operation) {
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case BLKIF_OP_READ:
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@ -559,11 +627,16 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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blkif->st_wr_req++;
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operation = WRITE_ODIRECT;
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break;
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case BLKIF_OP_WRITE_BARRIER:
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drain = true;
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case BLKIF_OP_FLUSH_DISKCACHE:
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blkif->st_f_req++;
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operation = WRITE_FLUSH;
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break;
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case BLKIF_OP_WRITE_BARRIER:
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case BLKIF_OP_DISCARD:
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blkif->st_ds_req++;
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operation = REQ_DISCARD;
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break;
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default:
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operation = 0; /* make gcc happy */
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goto fail_response;
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@ -572,7 +645,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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/* Check that the number of segments is sane. */
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nseg = req->nr_segments;
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if (unlikely(nseg == 0 && operation != WRITE_FLUSH) ||
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if (unlikely(nseg == 0 && operation != WRITE_FLUSH &&
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operation != REQ_DISCARD) ||
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unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) {
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pr_debug(DRV_PFX "Bad number of segments in request (%d)\n",
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nseg);
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@ -621,16 +695,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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}
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}
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/* Wait on all outstanding I/O's and once that has been completed
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* issue the WRITE_FLUSH.
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*/
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if (drain)
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xen_blk_drain_io(pending_req->blkif);
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/*
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* If we have failed at this point, we need to undo the M2P override,
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* set gnttab_set_unmap_op on all of the grant references and perform
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* the hypercall to unmap the grants - that is all done in
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* xen_blkbk_unmap.
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*/
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if (xen_blkbk_map(req, pending_req, seg))
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if (operation != REQ_DISCARD && xen_blkbk_map(req, pending_req, seg))
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goto fail_flush;
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/* This corresponding xen_blkif_put is done in __end_block_io_op */
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/*
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* This corresponding xen_blkif_put is done in __end_block_io_op, or
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* below (in "!bio") if we are handling a BLKIF_OP_DISCARD.
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*/
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xen_blkif_get(blkif);
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for (i = 0; i < nseg; i++) {
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@ -654,18 +737,25 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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preq.sector_number += seg[i].nsec;
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}
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/* This will be hit if the operation was a flush. */
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/* This will be hit if the operation was a flush or discard. */
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if (!bio) {
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BUG_ON(operation != WRITE_FLUSH);
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BUG_ON(operation != WRITE_FLUSH && operation != REQ_DISCARD);
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bio = bio_alloc(GFP_KERNEL, 0);
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if (unlikely(bio == NULL))
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goto fail_put_bio;
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if (operation == WRITE_FLUSH) {
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bio = bio_alloc(GFP_KERNEL, 0);
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if (unlikely(bio == NULL))
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goto fail_put_bio;
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biolist[nbio++] = bio;
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bio->bi_bdev = preq.bdev;
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bio->bi_private = pending_req;
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bio->bi_end_io = end_block_io_op;
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biolist[nbio++] = bio;
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bio->bi_bdev = preq.bdev;
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bio->bi_private = pending_req;
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bio->bi_end_io = end_block_io_op;
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} else if (operation == REQ_DISCARD) {
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xen_blk_discard(blkif, req);
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xen_blkif_put(blkif);
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free_req(pending_req);
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return 0;
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}
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}
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/*
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@ -685,7 +775,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
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if (operation == READ)
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blkif->st_rd_sect += preq.nr_sects;
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else if (operation == WRITE || operation == WRITE_FLUSH)
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else if (operation & WRITE)
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blkif->st_wr_sect += preq.nr_sects;
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return 0;
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@ -765,9 +855,9 @@ static int __init xen_blkif_init(void)
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mmap_pages = xen_blkif_reqs * BLKIF_MAX_SEGMENTS_PER_REQUEST;
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blkbk->pending_reqs = kmalloc(sizeof(blkbk->pending_reqs[0]) *
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blkbk->pending_reqs = kzalloc(sizeof(blkbk->pending_reqs[0]) *
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xen_blkif_reqs, GFP_KERNEL);
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blkbk->pending_grant_handles = kzalloc(sizeof(blkbk->pending_grant_handles[0]) *
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blkbk->pending_grant_handles = kmalloc(sizeof(blkbk->pending_grant_handles[0]) *
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mmap_pages, GFP_KERNEL);
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blkbk->pending_pages = kzalloc(sizeof(blkbk->pending_pages[0]) *
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mmap_pages, GFP_KERNEL);
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@ -790,8 +880,6 @@ static int __init xen_blkif_init(void)
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if (rc)
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goto failed_init;
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memset(blkbk->pending_reqs, 0, sizeof(blkbk->pending_reqs));
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INIT_LIST_HEAD(&blkbk->pending_free);
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spin_lock_init(&blkbk->pending_free_lock);
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init_waitqueue_head(&blkbk->pending_free_wq);
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|
|
|
@ -46,7 +46,7 @@
|
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|
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#define DRV_PFX "xen-blkback:"
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#define DPRINTK(fmt, args...) \
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pr_debug(DRV_PFX "(%s:%d) " fmt ".\n", \
|
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pr_debug(DRV_PFX "(%s:%d) " fmt ".\n", \
|
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__func__, __LINE__, ##args)
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|
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|
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|
@ -63,13 +63,26 @@ struct blkif_common_response {
|
|||
|
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/* i386 protocol version */
|
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#pragma pack(push, 4)
|
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|
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struct blkif_x86_32_request_rw {
|
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blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
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struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
|
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};
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|
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struct blkif_x86_32_request_discard {
|
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blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
|
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uint64_t nr_sectors;
|
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};
|
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|
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struct blkif_x86_32_request {
|
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uint8_t operation; /* BLKIF_OP_??? */
|
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uint8_t nr_segments; /* number of segments */
|
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blkif_vdev_t handle; /* only for read/write requests */
|
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uint64_t id; /* private guest value, echoed in resp */
|
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blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
|
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struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
|
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union {
|
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struct blkif_x86_32_request_rw rw;
|
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struct blkif_x86_32_request_discard discard;
|
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} u;
|
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};
|
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struct blkif_x86_32_response {
|
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uint64_t id; /* copied from request */
|
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|
@ -79,13 +92,26 @@ struct blkif_x86_32_response {
|
|||
#pragma pack(pop)
|
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|
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/* x86_64 protocol version */
|
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|
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struct blkif_x86_64_request_rw {
|
||||
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
|
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struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
|
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};
|
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|
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struct blkif_x86_64_request_discard {
|
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blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
|
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uint64_t nr_sectors;
|
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};
|
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|
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struct blkif_x86_64_request {
|
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uint8_t operation; /* BLKIF_OP_??? */
|
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uint8_t nr_segments; /* number of segments */
|
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blkif_vdev_t handle; /* only for read/write requests */
|
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uint64_t __attribute__((__aligned__(8))) id;
|
||||
blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
|
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struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
|
||||
union {
|
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struct blkif_x86_64_request_rw rw;
|
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struct blkif_x86_64_request_discard discard;
|
||||
} u;
|
||||
};
|
||||
struct blkif_x86_64_response {
|
||||
uint64_t __attribute__((__aligned__(8))) id;
|
||||
|
@ -113,6 +139,11 @@ enum blkif_protocol {
|
|||
BLKIF_PROTOCOL_X86_64 = 3,
|
||||
};
|
||||
|
||||
enum blkif_backend_type {
|
||||
BLKIF_BACKEND_PHY = 1,
|
||||
BLKIF_BACKEND_FILE = 2,
|
||||
};
|
||||
|
||||
struct xen_vbd {
|
||||
/* What the domain refers to this vbd as. */
|
||||
blkif_vdev_t handle;
|
||||
|
@ -138,6 +169,7 @@ struct xen_blkif {
|
|||
unsigned int irq;
|
||||
/* Comms information. */
|
||||
enum blkif_protocol blk_protocol;
|
||||
enum blkif_backend_type blk_backend_type;
|
||||
union blkif_back_rings blk_rings;
|
||||
struct vm_struct *blk_ring_area;
|
||||
/* The VBD attached to this interface. */
|
||||
|
@ -149,6 +181,9 @@ struct xen_blkif {
|
|||
atomic_t refcnt;
|
||||
|
||||
wait_queue_head_t wq;
|
||||
/* for barrier (drain) requests */
|
||||
struct completion drain_complete;
|
||||
atomic_t drain;
|
||||
/* One thread per one blkif. */
|
||||
struct task_struct *xenblkd;
|
||||
unsigned int waiting_reqs;
|
||||
|
@ -159,6 +194,7 @@ struct xen_blkif {
|
|||
int st_wr_req;
|
||||
int st_oo_req;
|
||||
int st_f_req;
|
||||
int st_ds_req;
|
||||
int st_rd_sect;
|
||||
int st_wr_sect;
|
||||
|
||||
|
@ -182,7 +218,7 @@ struct xen_blkif {
|
|||
|
||||
struct phys_req {
|
||||
unsigned short dev;
|
||||
unsigned short nr_sects;
|
||||
blkif_sector_t nr_sects;
|
||||
struct block_device *bdev;
|
||||
blkif_sector_t sector_number;
|
||||
};
|
||||
|
@ -196,6 +232,8 @@ int xen_blkif_schedule(void *arg);
|
|||
int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
|
||||
struct backend_info *be, int state);
|
||||
|
||||
int xen_blkbk_barrier(struct xenbus_transaction xbt,
|
||||
struct backend_info *be, int state);
|
||||
struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be);
|
||||
|
||||
static inline void blkif_get_x86_32_req(struct blkif_request *dst,
|
||||
|
@ -206,12 +244,25 @@ static inline void blkif_get_x86_32_req(struct blkif_request *dst,
|
|||
dst->nr_segments = src->nr_segments;
|
||||
dst->handle = src->handle;
|
||||
dst->id = src->id;
|
||||
dst->u.rw.sector_number = src->sector_number;
|
||||
barrier();
|
||||
if (n > dst->nr_segments)
|
||||
n = dst->nr_segments;
|
||||
for (i = 0; i < n; i++)
|
||||
dst->u.rw.seg[i] = src->seg[i];
|
||||
switch (src->operation) {
|
||||
case BLKIF_OP_READ:
|
||||
case BLKIF_OP_WRITE:
|
||||
case BLKIF_OP_WRITE_BARRIER:
|
||||
case BLKIF_OP_FLUSH_DISKCACHE:
|
||||
dst->u.rw.sector_number = src->u.rw.sector_number;
|
||||
barrier();
|
||||
if (n > dst->nr_segments)
|
||||
n = dst->nr_segments;
|
||||
for (i = 0; i < n; i++)
|
||||
dst->u.rw.seg[i] = src->u.rw.seg[i];
|
||||
break;
|
||||
case BLKIF_OP_DISCARD:
|
||||
dst->u.discard.sector_number = src->u.discard.sector_number;
|
||||
dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static inline void blkif_get_x86_64_req(struct blkif_request *dst,
|
||||
|
@ -222,12 +273,25 @@ static inline void blkif_get_x86_64_req(struct blkif_request *dst,
|
|||
dst->nr_segments = src->nr_segments;
|
||||
dst->handle = src->handle;
|
||||
dst->id = src->id;
|
||||
dst->u.rw.sector_number = src->sector_number;
|
||||
barrier();
|
||||
if (n > dst->nr_segments)
|
||||
n = dst->nr_segments;
|
||||
for (i = 0; i < n; i++)
|
||||
dst->u.rw.seg[i] = src->seg[i];
|
||||
switch (src->operation) {
|
||||
case BLKIF_OP_READ:
|
||||
case BLKIF_OP_WRITE:
|
||||
case BLKIF_OP_WRITE_BARRIER:
|
||||
case BLKIF_OP_FLUSH_DISKCACHE:
|
||||
dst->u.rw.sector_number = src->u.rw.sector_number;
|
||||
barrier();
|
||||
if (n > dst->nr_segments)
|
||||
n = dst->nr_segments;
|
||||
for (i = 0; i < n; i++)
|
||||
dst->u.rw.seg[i] = src->u.rw.seg[i];
|
||||
break;
|
||||
case BLKIF_OP_DISCARD:
|
||||
dst->u.discard.sector_number = src->u.discard.sector_number;
|
||||
dst->u.discard.nr_sectors = src->u.discard.nr_sectors;
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
#endif /* __XEN_BLKIF__BACKEND__COMMON_H__ */
|
||||
|
|
|
@ -114,6 +114,8 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
|
|||
spin_lock_init(&blkif->blk_ring_lock);
|
||||
atomic_set(&blkif->refcnt, 1);
|
||||
init_waitqueue_head(&blkif->wq);
|
||||
init_completion(&blkif->drain_complete);
|
||||
atomic_set(&blkif->drain, 0);
|
||||
blkif->st_print = jiffies;
|
||||
init_waitqueue_head(&blkif->waiting_to_free);
|
||||
|
||||
|
@ -272,6 +274,7 @@ VBD_SHOW(oo_req, "%d\n", be->blkif->st_oo_req);
|
|||
VBD_SHOW(rd_req, "%d\n", be->blkif->st_rd_req);
|
||||
VBD_SHOW(wr_req, "%d\n", be->blkif->st_wr_req);
|
||||
VBD_SHOW(f_req, "%d\n", be->blkif->st_f_req);
|
||||
VBD_SHOW(ds_req, "%d\n", be->blkif->st_ds_req);
|
||||
VBD_SHOW(rd_sect, "%d\n", be->blkif->st_rd_sect);
|
||||
VBD_SHOW(wr_sect, "%d\n", be->blkif->st_wr_sect);
|
||||
|
||||
|
@ -280,6 +283,7 @@ static struct attribute *xen_vbdstat_attrs[] = {
|
|||
&dev_attr_rd_req.attr,
|
||||
&dev_attr_wr_req.attr,
|
||||
&dev_attr_f_req.attr,
|
||||
&dev_attr_ds_req.attr,
|
||||
&dev_attr_rd_sect.attr,
|
||||
&dev_attr_wr_sect.attr,
|
||||
NULL
|
||||
|
@ -419,6 +423,73 @@ int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt,
|
|||
return err;
|
||||
}
|
||||
|
||||
int xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info *be)
|
||||
{
|
||||
struct xenbus_device *dev = be->dev;
|
||||
struct xen_blkif *blkif = be->blkif;
|
||||
char *type;
|
||||
int err;
|
||||
int state = 0;
|
||||
|
||||
type = xenbus_read(XBT_NIL, dev->nodename, "type", NULL);
|
||||
if (!IS_ERR(type)) {
|
||||
if (strncmp(type, "file", 4) == 0) {
|
||||
state = 1;
|
||||
blkif->blk_backend_type = BLKIF_BACKEND_FILE;
|
||||
}
|
||||
if (strncmp(type, "phy", 3) == 0) {
|
||||
struct block_device *bdev = be->blkif->vbd.bdev;
|
||||
struct request_queue *q = bdev_get_queue(bdev);
|
||||
if (blk_queue_discard(q)) {
|
||||
err = xenbus_printf(xbt, dev->nodename,
|
||||
"discard-granularity", "%u",
|
||||
q->limits.discard_granularity);
|
||||
if (err) {
|
||||
xenbus_dev_fatal(dev, err,
|
||||
"writing discard-granularity");
|
||||
goto kfree;
|
||||
}
|
||||
err = xenbus_printf(xbt, dev->nodename,
|
||||
"discard-alignment", "%u",
|
||||
q->limits.discard_alignment);
|
||||
if (err) {
|
||||
xenbus_dev_fatal(dev, err,
|
||||
"writing discard-alignment");
|
||||
goto kfree;
|
||||
}
|
||||
state = 1;
|
||||
blkif->blk_backend_type = BLKIF_BACKEND_PHY;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
err = PTR_ERR(type);
|
||||
xenbus_dev_fatal(dev, err, "reading type");
|
||||
goto out;
|
||||
}
|
||||
|
||||
err = xenbus_printf(xbt, dev->nodename, "feature-discard",
|
||||
"%d", state);
|
||||
if (err)
|
||||
xenbus_dev_fatal(dev, err, "writing feature-discard");
|
||||
kfree:
|
||||
kfree(type);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
int xen_blkbk_barrier(struct xenbus_transaction xbt,
|
||||
struct backend_info *be, int state)
|
||||
{
|
||||
struct xenbus_device *dev = be->dev;
|
||||
int err;
|
||||
|
||||
err = xenbus_printf(xbt, dev->nodename, "feature-barrier",
|
||||
"%d", state);
|
||||
if (err)
|
||||
xenbus_dev_fatal(dev, err, "writing feature-barrier");
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* Entry point to this code when a new device is created. Allocate the basic
|
||||
* structures, and watch the store waiting for the hotplug scripts to tell us
|
||||
|
@ -590,7 +661,7 @@ static void frontend_changed(struct xenbus_device *dev,
|
|||
|
||||
/*
|
||||
* Enforce precondition before potential leak point.
|
||||
* blkif_disconnect() is idempotent.
|
||||
* xen_blkif_disconnect() is idempotent.
|
||||
*/
|
||||
xen_blkif_disconnect(be->blkif);
|
||||
|
||||
|
@ -611,7 +682,7 @@ static void frontend_changed(struct xenbus_device *dev,
|
|||
break;
|
||||
/* fall through if not online */
|
||||
case XenbusStateUnknown:
|
||||
/* implies blkif_disconnect() via blkback_remove() */
|
||||
/* implies xen_blkif_disconnect() via xen_blkbk_remove() */
|
||||
device_unregister(&dev->dev);
|
||||
break;
|
||||
|
||||
|
@ -650,6 +721,11 @@ static void connect(struct backend_info *be)
|
|||
if (err)
|
||||
goto abort;
|
||||
|
||||
err = xen_blkbk_discard(xbt, be);
|
||||
|
||||
/* If we can't advertise it is OK. */
|
||||
err = xen_blkbk_barrier(xbt, be, be->blkif->vbd.flush_support);
|
||||
|
||||
err = xenbus_printf(xbt, dev->nodename, "sectors", "%llu",
|
||||
(unsigned long long)vbd_sz(&be->blkif->vbd));
|
||||
if (err) {
|
||||
|
|
|
@ -98,6 +98,9 @@ struct blkfront_info
|
|||
unsigned long shadow_free;
|
||||
unsigned int feature_flush;
|
||||
unsigned int flush_op;
|
||||
unsigned int feature_discard;
|
||||
unsigned int discard_granularity;
|
||||
unsigned int discard_alignment;
|
||||
int is_ready;
|
||||
};
|
||||
|
||||
|
@ -302,29 +305,36 @@ static int blkif_queue_request(struct request *req)
|
|||
ring_req->operation = info->flush_op;
|
||||
}
|
||||
|
||||
ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
|
||||
BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
|
||||
if (unlikely(req->cmd_flags & REQ_DISCARD)) {
|
||||
/* id, sector_number and handle are set above. */
|
||||
ring_req->operation = BLKIF_OP_DISCARD;
|
||||
ring_req->nr_segments = 0;
|
||||
ring_req->u.discard.nr_sectors = blk_rq_sectors(req);
|
||||
} else {
|
||||
ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
|
||||
BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
|
||||
|
||||
for_each_sg(info->sg, sg, ring_req->nr_segments, i) {
|
||||
buffer_mfn = pfn_to_mfn(page_to_pfn(sg_page(sg)));
|
||||
fsect = sg->offset >> 9;
|
||||
lsect = fsect + (sg->length >> 9) - 1;
|
||||
/* install a grant reference. */
|
||||
ref = gnttab_claim_grant_reference(&gref_head);
|
||||
BUG_ON(ref == -ENOSPC);
|
||||
for_each_sg(info->sg, sg, ring_req->nr_segments, i) {
|
||||
buffer_mfn = pfn_to_mfn(page_to_pfn(sg_page(sg)));
|
||||
fsect = sg->offset >> 9;
|
||||
lsect = fsect + (sg->length >> 9) - 1;
|
||||
/* install a grant reference. */
|
||||
ref = gnttab_claim_grant_reference(&gref_head);
|
||||
BUG_ON(ref == -ENOSPC);
|
||||
|
||||
gnttab_grant_foreign_access_ref(
|
||||
ref,
|
||||
info->xbdev->otherend_id,
|
||||
buffer_mfn,
|
||||
rq_data_dir(req) );
|
||||
gnttab_grant_foreign_access_ref(
|
||||
ref,
|
||||
info->xbdev->otherend_id,
|
||||
buffer_mfn,
|
||||
rq_data_dir(req));
|
||||
|
||||
info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
|
||||
ring_req->u.rw.seg[i] =
|
||||
(struct blkif_request_segment) {
|
||||
.gref = ref,
|
||||
.first_sect = fsect,
|
||||
.last_sect = lsect };
|
||||
info->shadow[id].frame[i] = mfn_to_pfn(buffer_mfn);
|
||||
ring_req->u.rw.seg[i] =
|
||||
(struct blkif_request_segment) {
|
||||
.gref = ref,
|
||||
.first_sect = fsect,
|
||||
.last_sect = lsect };
|
||||
}
|
||||
}
|
||||
|
||||
info->ring.req_prod_pvt++;
|
||||
|
@ -370,7 +380,9 @@ static void do_blkif_request(struct request_queue *rq)
|
|||
|
||||
blk_start_request(req);
|
||||
|
||||
if (req->cmd_type != REQ_TYPE_FS) {
|
||||
if ((req->cmd_type != REQ_TYPE_FS) ||
|
||||
((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) &&
|
||||
!info->flush_op)) {
|
||||
__blk_end_request_all(req, -EIO);
|
||||
continue;
|
||||
}
|
||||
|
@ -399,6 +411,7 @@ static void do_blkif_request(struct request_queue *rq)
|
|||
static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
|
||||
{
|
||||
struct request_queue *rq;
|
||||
struct blkfront_info *info = gd->private_data;
|
||||
|
||||
rq = blk_init_queue(do_blkif_request, &blkif_io_lock);
|
||||
if (rq == NULL)
|
||||
|
@ -406,6 +419,13 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
|
|||
|
||||
queue_flag_set_unlocked(QUEUE_FLAG_VIRT, rq);
|
||||
|
||||
if (info->feature_discard) {
|
||||
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, rq);
|
||||
blk_queue_max_discard_sectors(rq, get_capacity(gd));
|
||||
rq->limits.discard_granularity = info->discard_granularity;
|
||||
rq->limits.discard_alignment = info->discard_alignment;
|
||||
}
|
||||
|
||||
/* Hard sector size and max sectors impersonate the equiv. hardware. */
|
||||
blk_queue_logical_block_size(rq, sector_size);
|
||||
blk_queue_max_hw_sectors(rq, 512);
|
||||
|
@ -722,6 +742,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
|
|||
|
||||
error = (bret->status == BLKIF_RSP_OKAY) ? 0 : -EIO;
|
||||
switch (bret->operation) {
|
||||
case BLKIF_OP_DISCARD:
|
||||
if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
|
||||
struct request_queue *rq = info->rq;
|
||||
printk(KERN_WARNING "blkfront: %s: discard op failed\n",
|
||||
info->gd->disk_name);
|
||||
error = -EOPNOTSUPP;
|
||||
info->feature_discard = 0;
|
||||
queue_flag_clear(QUEUE_FLAG_DISCARD, rq);
|
||||
}
|
||||
__blk_end_request_all(req, error);
|
||||
break;
|
||||
case BLKIF_OP_FLUSH_DISKCACHE:
|
||||
case BLKIF_OP_WRITE_BARRIER:
|
||||
if (unlikely(bret->status == BLKIF_RSP_EOPNOTSUPP)) {
|
||||
|
@ -1098,6 +1129,33 @@ blkfront_closing(struct blkfront_info *info)
|
|||
bdput(bdev);
|
||||
}
|
||||
|
||||
static void blkfront_setup_discard(struct blkfront_info *info)
|
||||
{
|
||||
int err;
|
||||
char *type;
|
||||
unsigned int discard_granularity;
|
||||
unsigned int discard_alignment;
|
||||
|
||||
type = xenbus_read(XBT_NIL, info->xbdev->otherend, "type", NULL);
|
||||
if (IS_ERR(type))
|
||||
return;
|
||||
|
||||
if (strncmp(type, "phy", 3) == 0) {
|
||||
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
|
||||
"discard-granularity", "%u", &discard_granularity,
|
||||
"discard-alignment", "%u", &discard_alignment,
|
||||
NULL);
|
||||
if (!err) {
|
||||
info->feature_discard = 1;
|
||||
info->discard_granularity = discard_granularity;
|
||||
info->discard_alignment = discard_alignment;
|
||||
}
|
||||
} else if (strncmp(type, "file", 4) == 0)
|
||||
info->feature_discard = 1;
|
||||
|
||||
kfree(type);
|
||||
}
|
||||
|
||||
/*
|
||||
* Invoked when the backend is finally 'ready' (and has told produced
|
||||
* the details about the physical device - #sectors, size, etc).
|
||||
|
@ -1108,7 +1166,7 @@ static void blkfront_connect(struct blkfront_info *info)
|
|||
unsigned long sector_size;
|
||||
unsigned int binfo;
|
||||
int err;
|
||||
int barrier, flush;
|
||||
int barrier, flush, discard;
|
||||
|
||||
switch (info->connected) {
|
||||
case BLKIF_STATE_CONNECTED:
|
||||
|
@ -1178,7 +1236,14 @@ static void blkfront_connect(struct blkfront_info *info)
|
|||
info->feature_flush = REQ_FLUSH;
|
||||
info->flush_op = BLKIF_OP_FLUSH_DISKCACHE;
|
||||
}
|
||||
|
||||
|
||||
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
|
||||
"feature-discard", "%d", &discard,
|
||||
NULL);
|
||||
|
||||
if (!err && discard)
|
||||
blkfront_setup_discard(info);
|
||||
|
||||
err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size);
|
||||
if (err) {
|
||||
xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s",
|
||||
|
@ -1385,6 +1450,8 @@ static struct xenbus_driver blkfront = {
|
|||
|
||||
static int __init xlblk_init(void)
|
||||
{
|
||||
int ret;
|
||||
|
||||
if (!xen_domain())
|
||||
return -ENODEV;
|
||||
|
||||
|
@ -1394,7 +1461,13 @@ static int __init xlblk_init(void)
|
|||
return -ENODEV;
|
||||
}
|
||||
|
||||
return xenbus_register_frontend(&blkfront);
|
||||
ret = xenbus_register_frontend(&blkfront);
|
||||
if (ret) {
|
||||
unregister_blkdev(XENVBD_MAJOR, DEV_NAME);
|
||||
return ret;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
module_init(xlblk_init);
|
||||
|
||||
|
|
|
@ -57,6 +57,36 @@ typedef uint64_t blkif_sector_t;
|
|||
* "feature-flush-cache" node!
|
||||
*/
|
||||
#define BLKIF_OP_FLUSH_DISKCACHE 3
|
||||
|
||||
/*
|
||||
* Recognised only if "feature-discard" is present in backend xenbus info.
|
||||
* The "feature-discard" node contains a boolean indicating whether trim
|
||||
* (ATA) or unmap (SCSI) - conviently called discard requests are likely
|
||||
* to succeed or fail. Either way, a discard request
|
||||
* may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
|
||||
* the underlying block-device hardware. The boolean simply indicates whether
|
||||
* or not it is worthwhile for the frontend to attempt discard requests.
|
||||
* If a backend does not recognise BLKIF_OP_DISCARD, it should *not*
|
||||
* create the "feature-discard" node!
|
||||
*
|
||||
* Discard operation is a request for the underlying block device to mark
|
||||
* extents to be erased. However, discard does not guarantee that the blocks
|
||||
* will be erased from the device - it is just a hint to the device
|
||||
* controller that these blocks are no longer in use. What the device
|
||||
* controller does with that information is left to the controller.
|
||||
* Discard operations are passed with sector_number as the
|
||||
* sector index to begin discard operations at and nr_sectors as the number of
|
||||
* sectors to be discarded. The specified sectors should be discarded if the
|
||||
* underlying block device supports trim (ATA) or unmap (SCSI) operations,
|
||||
* or a BLKIF_RSP_EOPNOTSUPP should be returned.
|
||||
* More information about trim/unmap operations at:
|
||||
* http://t13.org/Documents/UploadedDocuments/docs2008/
|
||||
* e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc
|
||||
* http://www.seagate.com/staticfiles/support/disc/manuals/
|
||||
* Interface%20manuals/100293068c.pdf
|
||||
*/
|
||||
#define BLKIF_OP_DISCARD 5
|
||||
|
||||
/*
|
||||
* Maximum scatter/gather segments per request.
|
||||
* This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE.
|
||||
|
@ -74,6 +104,11 @@ struct blkif_request_rw {
|
|||
} seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
|
||||
};
|
||||
|
||||
struct blkif_request_discard {
|
||||
blkif_sector_t sector_number;
|
||||
uint64_t nr_sectors;
|
||||
};
|
||||
|
||||
struct blkif_request {
|
||||
uint8_t operation; /* BLKIF_OP_??? */
|
||||
uint8_t nr_segments; /* number of segments */
|
||||
|
@ -81,6 +116,7 @@ struct blkif_request {
|
|||
uint64_t id; /* private guest value, echoed in resp */
|
||||
union {
|
||||
struct blkif_request_rw rw;
|
||||
struct blkif_request_discard discard;
|
||||
} u;
|
||||
};
|
||||
|
||||
|
|
Loading…
Reference in a new issue