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path: root/drivers/block/xen-blkback/blkback.c
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Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
-rw-r--r--drivers/block/xen-blkback/blkback.c91
1 files changed, 53 insertions, 38 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 74374fb762aa..dd5b2fed97e9 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -46,6 +46,7 @@
#include <xen/xen.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
+#include <xen/balloon.h>
#include "common.h"
/*
@@ -161,10 +162,12 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
static void make_response(struct xen_blkif *blkif, u64 id,
unsigned short op, int st);
-#define foreach_grant(pos, rbtree, node) \
- for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node); \
+#define foreach_grant_safe(pos, n, rbtree, node) \
+ for ((pos) = container_of(rb_first((rbtree)), typeof(*(pos)), node), \
+ (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL; \
&(pos)->node != NULL; \
- (pos) = container_of(rb_next(&(pos)->node), typeof(*(pos)), node))
+ (pos) = container_of(n, typeof(*(pos)), node), \
+ (n) = (&(pos)->node != NULL) ? rb_next(&(pos)->node) : NULL)
static void add_persistent_gnt(struct rb_root *root,
@@ -217,10 +220,11 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num)
struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST];
struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST];
struct persistent_gnt *persistent_gnt;
+ struct rb_node *n;
int ret = 0;
int segs_to_unmap = 0;
- foreach_grant(persistent_gnt, root, node) {
+ foreach_grant_safe(persistent_gnt, n, root, node) {
BUG_ON(persistent_gnt->handle ==
BLKBACK_INVALID_HANDLE);
gnttab_set_unmap_op(&unmap[segs_to_unmap],
@@ -230,17 +234,19 @@ static void free_persistent_gnts(struct rb_root *root, unsigned int num)
persistent_gnt->handle);
pages[segs_to_unmap] = persistent_gnt->page;
- rb_erase(&persistent_gnt->node, root);
- kfree(persistent_gnt);
- num--;
if (++segs_to_unmap == BLKIF_MAX_SEGMENTS_PER_REQUEST ||
!rb_next(&persistent_gnt->node)) {
ret = gnttab_unmap_refs(unmap, NULL, pages,
segs_to_unmap);
BUG_ON(ret);
+ free_xenballooned_pages(segs_to_unmap, pages);
segs_to_unmap = 0;
}
+
+ rb_erase(&persistent_gnt->node, root);
+ kfree(persistent_gnt);
+ num--;
}
BUG_ON(num != 0);
}
@@ -375,8 +381,8 @@ irqreturn_t xen_blkif_be_int(int irq, void *dev_id)
static void print_stats(struct xen_blkif *blkif)
{
- pr_info("xen-blkback (%s): oo %3d | rd %4d | wr %4d | f %4d"
- " | ds %4d\n",
+ pr_info("xen-blkback (%s): oo %3llu | rd %4llu | wr %4llu | f %4llu"
+ " | ds %4llu\n",
current->comm, blkif->st_oo_req,
blkif->st_rd_req, blkif->st_wr_req,
blkif->st_f_req, blkif->st_ds_req);
@@ -436,7 +442,7 @@ int xen_blkif_schedule(void *arg)
}
struct seg_buf {
- unsigned long buf;
+ unsigned int offset;
unsigned int nsec;
};
/*
@@ -523,8 +529,8 @@ static int xen_blkbk_map(struct blkif_request *req,
GFP_KERNEL);
if (!persistent_gnt)
return -ENOMEM;
- persistent_gnt->page = alloc_page(GFP_KERNEL);
- if (!persistent_gnt->page) {
+ if (alloc_xenballooned_pages(1, &persistent_gnt->page,
+ false)) {
kfree(persistent_gnt);
return -ENOMEM;
}
@@ -615,30 +621,21 @@ static int xen_blkbk_map(struct blkif_request *req,
* If this is a new persistent grant
* save the handler
*/
- persistent_gnts[i]->handle = map[j].handle;
- persistent_gnts[i]->dev_bus_addr =
- map[j++].dev_bus_addr;
+ persistent_gnts[i]->handle = map[j++].handle;
}
pending_handle(pending_req, i) =
persistent_gnts[i]->handle;
if (ret)
continue;
-
- seg[i].buf = persistent_gnts[i]->dev_bus_addr |
- (req->u.rw.seg[i].first_sect << 9);
} else {
- pending_handle(pending_req, i) = map[j].handle;
+ pending_handle(pending_req, i) = map[j++].handle;
bitmap_set(pending_req->unmap_seg, i, 1);
- if (ret) {
- j++;
+ if (ret)
continue;
- }
-
- seg[i].buf = map[j++].dev_bus_addr |
- (req->u.rw.seg[i].first_sect << 9);
}
+ seg[i].offset = (req->u.rw.seg[i].first_sect << 9);
}
return ret;
}
@@ -673,6 +670,16 @@ static int dispatch_discard_io(struct xen_blkif *blkif,
return err;
}
+static int dispatch_other_io(struct xen_blkif *blkif,
+ struct blkif_request *req,
+ struct pending_req *pending_req)
+{
+ free_req(pending_req);
+ make_response(blkif, req->u.other.id, req->operation,
+ BLKIF_RSP_EOPNOTSUPP);
+ return -EIO;
+}
+
static void xen_blk_drain_io(struct xen_blkif *blkif)
{
atomic_set(&blkif->drain, 1);
@@ -794,17 +801,30 @@ __do_block_io_op(struct xen_blkif *blkif)
/* Apply all sanity checks to /private copy/ of request. */
barrier();
- if (unlikely(req.operation == BLKIF_OP_DISCARD)) {
+
+ switch (req.operation) {
+ case BLKIF_OP_READ:
+ case BLKIF_OP_WRITE:
+ case BLKIF_OP_WRITE_BARRIER:
+ case BLKIF_OP_FLUSH_DISKCACHE:
+ if (dispatch_rw_block_io(blkif, &req, pending_req))
+ goto done;
+ break;
+ case BLKIF_OP_DISCARD:
free_req(pending_req);
if (dispatch_discard_io(blkif, &req))
- break;
- } else if (dispatch_rw_block_io(blkif, &req, pending_req))
+ goto done;
+ break;
+ default:
+ if (dispatch_other_io(blkif, &req, pending_req))
+ goto done;
break;
+ }
/* Yield point for this unbounded loop. */
cond_resched();
}
-
+done:
return more_to_do;
}
@@ -875,7 +895,6 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
goto fail_response;
}
- preq.dev = req->u.rw.handle;
preq.sector_number = req->u.rw.sector_number;
preq.nr_sects = 0;
@@ -899,7 +918,8 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
pr_debug(DRV_PFX "access denied: %s of [%llu,%llu] on dev=%04x\n",
operation == READ ? "read" : "write",
preq.sector_number,
- preq.sector_number + preq.nr_sects, preq.dev);
+ preq.sector_number + preq.nr_sects,
+ blkif->vbd.pdevice);
goto fail_response;
}
@@ -942,7 +962,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
(bio_add_page(bio,
pages[i],
seg[i].nsec << 9,
- seg[i].buf & ~PAGE_MASK) == 0)) {
+ seg[i].offset) == 0)) {
bio = bio_alloc(GFP_KERNEL, nseg-i);
if (unlikely(bio == NULL))
@@ -972,13 +992,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
bio->bi_end_io = end_block_io_op;
}
- /*
- * We set it one so that the last submit_bio does not have to call
- * atomic_inc.
- */
atomic_set(&pending_req->pendcnt, nbio);
-
- /* Get a reference count for the disk queue and start sending I/O */
blk_start_plug(&plug);
for (i = 0; i < nbio; i++)
@@ -1006,6 +1020,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
fail_put_bio:
for (i = 0; i < nbio; i++)
bio_put(biolist[i]);
+ atomic_set(&pending_req->pendcnt, 1);
__end_block_io_op(pending_req, -EINVAL);
msleep(1); /* back off a bit */
return -EIO;