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authorLinus Torvalds <torvalds@linux-foundation.org>2016-07-07 15:34:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-07-07 15:34:09 -0700
commitac904ae6e6f0a56be7b9a1cf66fbd50dd025fb06 (patch)
tree381a6ad5886a0da78392c2f5bb817dd5d75ea97f
parent4c2a8499a450b6582eb5637a8f0d472168355ddd (diff)
parent8ba8682107ee2ca3347354e018865d8e1967c5f4 (diff)
downloadlinux-stericsson-ac904ae6e6f0a56be7b9a1cf66fbd50dd025fb06.tar.gz
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block IO fixes from Jens Axboe: "Three small fixes that have been queued up and tested for this series: - A bug fix for xen-blkfront from Bob Liu, fixing an issue with incomplete requests during migration. - A fix for an ancient issue in retrieving the IO priority of a different PID than self, preventing that task from going away while we access it. From Omar. - A writeback fix from Tahsin, fixing a case where we'd call ihold() with a zero ref count inode" * 'for-linus' of git://git.kernel.dk/linux-block: block: fix use-after-free in sys_ioprio_get() writeback: inode cgroup wb switch should not call ihold() xen-blkfront: save uncompleted reqs in blkfront_resume()
-rw-r--r--block/ioprio.c2
-rw-r--r--drivers/block/xen-blkfront.c91
-rw-r--r--fs/fs-writeback.c2
3 files changed, 43 insertions, 52 deletions
diff --git a/block/ioprio.c b/block/ioprio.c
index cc7800e9eb44..01b8116298a1 100644
--- a/block/ioprio.c
+++ b/block/ioprio.c
@@ -150,8 +150,10 @@ static int get_task_ioprio(struct task_struct *p)
if (ret)
goto out;
ret = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, IOPRIO_NORM);
+ task_lock(p);
if (p->io_context)
ret = p->io_context->ioprio;
+ task_unlock(p);
out:
return ret;
}
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 2e6d1e9c3345..fcc5b4e0aef2 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -207,6 +207,9 @@ struct blkfront_info
struct blk_mq_tag_set tag_set;
struct blkfront_ring_info *rinfo;
unsigned int nr_rings;
+ /* Save uncomplete reqs and bios for migration. */
+ struct list_head requests;
+ struct bio_list bio_list;
};
static unsigned int nr_minors;
@@ -2002,69 +2005,22 @@ static int blkif_recover(struct blkfront_info *info)
{
unsigned int i, r_index;
struct request *req, *n;
- struct blk_shadow *copy;
int rc;
struct bio *bio, *cloned_bio;
- struct bio_list bio_list, merge_bio;
unsigned int segs, offset;
int pending, size;
struct split_bio *split_bio;
- struct list_head requests;
blkfront_gather_backend_features(info);
segs = info->max_indirect_segments ? : BLKIF_MAX_SEGMENTS_PER_REQUEST;
blk_queue_max_segments(info->rq, segs);
- bio_list_init(&bio_list);
- INIT_LIST_HEAD(&requests);
for (r_index = 0; r_index < info->nr_rings; r_index++) {
- struct blkfront_ring_info *rinfo;
-
- rinfo = &info->rinfo[r_index];
- /* Stage 1: Make a safe copy of the shadow state. */
- copy = kmemdup(rinfo->shadow, sizeof(rinfo->shadow),
- GFP_NOIO | __GFP_REPEAT | __GFP_HIGH);
- if (!copy)
- return -ENOMEM;
-
- /* Stage 2: Set up free list. */
- memset(&rinfo->shadow, 0, sizeof(rinfo->shadow));
- for (i = 0; i < BLK_RING_SIZE(info); i++)
- rinfo->shadow[i].req.u.rw.id = i+1;
- rinfo->shadow_free = rinfo->ring.req_prod_pvt;
- rinfo->shadow[BLK_RING_SIZE(info)-1].req.u.rw.id = 0x0fffffff;
+ struct blkfront_ring_info *rinfo = &info->rinfo[r_index];
rc = blkfront_setup_indirect(rinfo);
- if (rc) {
- kfree(copy);
+ if (rc)
return rc;
- }
-
- for (i = 0; i < BLK_RING_SIZE(info); i++) {
- /* Not in use? */
- if (!copy[i].request)
- continue;
-
- /*
- * Get the bios in the request so we can re-queue them.
- */
- if (copy[i].request->cmd_flags &
- (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) {
- /*
- * Flush operations don't contain bios, so
- * we need to requeue the whole request
- */
- list_add(&copy[i].request->queuelist, &requests);
- continue;
- }
- merge_bio.head = copy[i].request->bio;
- merge_bio.tail = copy[i].request->biotail;
- bio_list_merge(&bio_list, &merge_bio);
- copy[i].request->bio = NULL;
- blk_end_request_all(copy[i].request, 0);
- }
-
- kfree(copy);
}
xenbus_switch_state(info->xbdev, XenbusStateConnected);
@@ -2079,7 +2035,7 @@ static int blkif_recover(struct blkfront_info *info)
kick_pending_request_queues(rinfo);
}
- list_for_each_entry_safe(req, n, &requests, queuelist) {
+ list_for_each_entry_safe(req, n, &info->requests, queuelist) {
/* Requeue pending requests (flush or discard) */
list_del_init(&req->queuelist);
BUG_ON(req->nr_phys_segments > segs);
@@ -2087,7 +2043,7 @@ static int blkif_recover(struct blkfront_info *info)
}
blk_mq_kick_requeue_list(info->rq);
- while ((bio = bio_list_pop(&bio_list)) != NULL) {
+ while ((bio = bio_list_pop(&info->bio_list)) != NULL) {
/* Traverse the list of pending bios and re-queue them */
if (bio_segments(bio) > segs) {
/*
@@ -2133,9 +2089,42 @@ static int blkfront_resume(struct xenbus_device *dev)
{
struct blkfront_info *info = dev_get_drvdata(&dev->dev);
int err = 0;
+ unsigned int i, j;
dev_dbg(&dev->dev, "blkfront_resume: %s\n", dev->nodename);
+ bio_list_init(&info->bio_list);
+ INIT_LIST_HEAD(&info->requests);
+ for (i = 0; i < info->nr_rings; i++) {
+ struct blkfront_ring_info *rinfo = &info->rinfo[i];
+ struct bio_list merge_bio;
+ struct blk_shadow *shadow = rinfo->shadow;
+
+ for (j = 0; j < BLK_RING_SIZE(info); j++) {
+ /* Not in use? */
+ if (!shadow[j].request)
+ continue;
+
+ /*
+ * Get the bios in the request so we can re-queue them.
+ */
+ if (shadow[j].request->cmd_flags &
+ (REQ_FLUSH | REQ_FUA | REQ_DISCARD | REQ_SECURE)) {
+ /*
+ * Flush operations don't contain bios, so
+ * we need to requeue the whole request
+ */
+ list_add(&shadow[j].request->queuelist, &info->requests);
+ continue;
+ }
+ merge_bio.head = shadow[j].request->bio;
+ merge_bio.tail = shadow[j].request->biotail;
+ bio_list_merge(&info->bio_list, &merge_bio);
+ shadow[j].request->bio = NULL;
+ blk_mq_end_request(shadow[j].request, 0);
+ }
+ }
+
blkif_free(info, info->connected == BLKIF_STATE_CONNECTED);
err = negotiate_mq(info);
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 989a2cef6b76..fe7e83a45eff 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -483,9 +483,9 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
goto out_free;
}
inode->i_state |= I_WB_SWITCH;
+ __iget(inode);
spin_unlock(&inode->i_lock);
- ihold(inode);
isw->inode = inode;
atomic_inc(&isw_nr_in_flight);