Merge branch 'stable/for-jens-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip into for-3.16/drivers

Konrad writes:

Please git pull the following branch:

git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git stable/for-jens-3.16

which has a bunch of fixes to the Xen block frontend and backend driver
and a new parameter for Xen backend driver - an override (set by the toolstack)
whether to expose the discard support (if disk of course supports it) or not.
This commit is contained in:
Jens Axboe 2014-05-28 12:37:04 -06:00
commit 879466e6a5
4 changed files with 57 additions and 42 deletions

View File

@ -314,7 +314,7 @@ struct xen_blkif {
unsigned long long st_rd_sect;
unsigned long long st_wr_sect;
wait_queue_head_t waiting_to_free;
struct work_struct free_work;
/* Thread shutdown wait queue. */
wait_queue_head_t shutdown_wq;
};
@ -361,7 +361,7 @@ struct pending_req {
#define xen_blkif_put(_b) \
do { \
if (atomic_dec_and_test(&(_b)->refcnt)) \
wake_up(&(_b)->waiting_to_free);\
schedule_work(&(_b)->free_work);\
} while (0)
struct phys_req {

View File

@ -35,12 +35,26 @@ static void connect(struct backend_info *);
static int connect_ring(struct backend_info *);
static void backend_changed(struct xenbus_watch *, const char **,
unsigned int);
static void xen_blkif_free(struct xen_blkif *blkif);
static void xen_vbd_free(struct xen_vbd *vbd);
struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be)
{
return be->dev;
}
/*
* The last request could free the device from softirq context and
* xen_blkif_free() can sleep.
*/
static void xen_blkif_deferred_free(struct work_struct *work)
{
struct xen_blkif *blkif;
blkif = container_of(work, struct xen_blkif, free_work);
xen_blkif_free(blkif);
}
static int blkback_name(struct xen_blkif *blkif, char *buf)
{
char *devpath, *devname;
@ -121,7 +135,6 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
init_completion(&blkif->drain_complete);
atomic_set(&blkif->drain, 0);
blkif->st_print = jiffies;
init_waitqueue_head(&blkif->waiting_to_free);
blkif->persistent_gnts.rb_node = NULL;
spin_lock_init(&blkif->free_pages_lock);
INIT_LIST_HEAD(&blkif->free_pages);
@ -132,6 +145,7 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
INIT_WORK(&blkif->persistent_purge_work, xen_blkbk_unmap_purged_grants);
INIT_LIST_HEAD(&blkif->pending_free);
INIT_WORK(&blkif->free_work, xen_blkif_deferred_free);
for (i = 0; i < XEN_BLKIF_REQS; i++) {
req = kzalloc(sizeof(*req), GFP_KERNEL);
@ -231,7 +245,7 @@ static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page,
return 0;
}
static void xen_blkif_disconnect(struct xen_blkif *blkif)
static int xen_blkif_disconnect(struct xen_blkif *blkif)
{
if (blkif->xenblkd) {
kthread_stop(blkif->xenblkd);
@ -239,9 +253,12 @@ static void xen_blkif_disconnect(struct xen_blkif *blkif)
blkif->xenblkd = NULL;
}
atomic_dec(&blkif->refcnt);
wait_event(blkif->waiting_to_free, atomic_read(&blkif->refcnt) == 0);
atomic_inc(&blkif->refcnt);
/* The above kthread_stop() guarantees that at this point we
* don't have any discard_io or other_io requests. So, checking
* for inflight IO is enough.
*/
if (atomic_read(&blkif->inflight) > 0)
return -EBUSY;
if (blkif->irq) {
unbind_from_irqhandler(blkif->irq, blkif);
@ -252,6 +269,8 @@ static void xen_blkif_disconnect(struct xen_blkif *blkif)
xenbus_unmap_ring_vfree(blkif->be->dev, blkif->blk_ring);
blkif->blk_rings.common.sring = NULL;
}
return 0;
}
static void xen_blkif_free(struct xen_blkif *blkif)
@ -259,8 +278,8 @@ static void xen_blkif_free(struct xen_blkif *blkif)
struct pending_req *req, *n;
int i = 0, j;
if (!atomic_dec_and_test(&blkif->refcnt))
BUG();
xen_blkif_disconnect(blkif);
xen_vbd_free(&blkif->vbd);
/* Remove all persistent grants and the cache of ballooned pages. */
xen_blkbk_free_caches(blkif);
@ -449,16 +468,15 @@ static int xen_blkbk_remove(struct xenbus_device *dev)
be->backend_watch.node = NULL;
}
dev_set_drvdata(&dev->dev, NULL);
if (be->blkif) {
xen_blkif_disconnect(be->blkif);
xen_vbd_free(&be->blkif->vbd);
xen_blkif_free(be->blkif);
be->blkif = NULL;
xen_blkif_put(be->blkif);
}
kfree(be->mode);
kfree(be);
dev_set_drvdata(&dev->dev, NULL);
return 0;
}
@ -481,10 +499,15 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info
struct xenbus_device *dev = be->dev;
struct xen_blkif *blkif = be->blkif;
int err;
int state = 0;
int state = 0, discard_enable;
struct block_device *bdev = be->blkif->vbd.bdev;
struct request_queue *q = bdev_get_queue(bdev);
err = xenbus_scanf(XBT_NIL, dev->nodename, "discard-enable", "%d",
&discard_enable);
if (err == 1 && !discard_enable)
return;
if (blk_queue_discard(q)) {
err = xenbus_printf(xbt, dev->nodename,
"discard-granularity", "%u",
@ -700,7 +723,11 @@ static void frontend_changed(struct xenbus_device *dev,
* Enforce precondition before potential leak point.
* xen_blkif_disconnect() is idempotent.
*/
xen_blkif_disconnect(be->blkif);
err = xen_blkif_disconnect(be->blkif);
if (err) {
xenbus_dev_fatal(dev, err, "pending I/O");
break;
}
err = connect_ring(be);
if (err)

View File

@ -1635,36 +1635,24 @@ blkfront_closing(struct blkfront_info *info)
static void blkfront_setup_discard(struct blkfront_info *info)
{
int err;
char *type;
unsigned int discard_granularity;
unsigned int discard_alignment;
unsigned int discard_secure;
type = xenbus_read(XBT_NIL, info->xbdev->otherend, "type", NULL);
if (IS_ERR(type))
return;
info->feature_secdiscard = 0;
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;
}
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"discard-secure", "%d", &discard_secure,
NULL);
if (!err)
info->feature_secdiscard = discard_secure;
} else if (strncmp(type, "file", 4) == 0)
info->feature_discard = 1;
kfree(type);
info->feature_discard = 1;
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"discard-granularity", "%u", &discard_granularity,
"discard-alignment", "%u", &discard_alignment,
NULL);
if (!err) {
info->discard_granularity = discard_granularity;
info->discard_alignment = discard_alignment;
}
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"discard-secure", "%d", &discard_secure,
NULL);
if (!err)
info->feature_secdiscard = !!discard_secure;
}
static int blkfront_setup_indirect(struct blkfront_info *info)

View File

@ -86,7 +86,7 @@ typedef uint64_t blkif_sector_t;
* Interface%20manuals/100293068c.pdf
* The backend can optionally provide three extra XenBus attributes to
* further optimize the discard functionality:
* 'discard-aligment' - Devices that support discard functionality may
* 'discard-alignment' - Devices that support discard functionality may
* internally allocate space in units that are bigger than the exported
* logical block size. The discard-alignment parameter indicates how many bytes
* the beginning of the partition is offset from the internal allocation unit's