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author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-03-13 18:43:23 -0400 |
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committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-03-24 10:04:35 -0400 |
commit | 4dae76705fc8f9854bb732f9944e7ff9ba7a8e9f (patch) | |
tree | e08b16f2ade9d05ac84e7ed8a36a10269dda4569 /drivers/block/xen-blkback/xenbus.c | |
parent | bc67f63650fad6b3478d9ddfd5406d45a95987c9 (diff) | |
download | op-kernel-dev-4dae76705fc8f9854bb732f9944e7ff9ba7a8e9f.zip op-kernel-dev-4dae76705fc8f9854bb732f9944e7ff9ba7a8e9f.tar.gz |
xen/blkback: Squash the discard support for 'file' and 'phy' type.
The only reason for the distinction was for the special case of
'file' (which is assumed to be loopback device), was to reach inside
the loopback device, find the underlaying file, and call fallocate on it.
Fortunately "xen-blkback: convert hole punching to discard request on
loop devices" removes that use-case and we now based the discard
support based on blk_queue_discard(q) and extract all appropriate
parameters from the 'struct request_queue'.
CC: Li Dongyang <lidongyang@novell.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
[v1: Dropping pointless initializer and keeping blank line]
[v2: Remove the kfree as it is not used anymore]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkback/xenbus.c')
-rw-r--r-- | drivers/block/xen-blkback/xenbus.c | 70 |
1 files changed, 26 insertions, 44 deletions
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 24a2fb5..d417c13 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -390,61 +390,43 @@ 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; + struct block_device *bdev = be->blkif->vbd.bdev; + struct request_queue *q = bdev_get_queue(bdev); - 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 (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 out; + } + err = xenbus_printf(xbt, dev->nodename, + "discard-alignment", "%u", + q->limits.discard_alignment); + if (err) { + xenbus_dev_fatal(dev, err, + "writing discard-alignment"); + goto out; } - 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; - } - /* Optional. */ - err = xenbus_printf(xbt, dev->nodename, - "discard-secure", "%d", - blkif->vbd.discard_secure); - if (err) { - xenbus_dev_fatal(dev, err, + state = 1; + /* Optional. */ + err = xenbus_printf(xbt, dev->nodename, + "discard-secure", "%d", + blkif->vbd.discard_secure); + if (err) { + xenbus_dev_fatal(dev, err, "writting discard-secure"); - goto kfree; - } + goto out; } - } 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; } |