linux-stable.git/drivers/block, branch v3.10.45

xen-blkfront: restore the non-persistent data path

2014-06-07T20:25:37+00:00

commit bfe11d6de1c416cea4f3f0f35f864162063ce3fa upstream.

When persistent grants were added they were always used, even if the
backend doesn't have this feature (there's no harm in always using the
same set of pages). This restores the old data path when the backend
doesn't have persistent grants, removing the burden of doing a memcpy
when it is not actually needed.

Signed-off-by: Roger Pau Monné 
Reported-by: Felipe Franciosi 
Cc: Felipe Franciosi 
Cc: Konrad Rzeszutek Wilk 
Cc: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk 
[v2: Fix up whitespace issues]
Tested-by: Felipe Franciosi 
Signed-off-by: Greg Kroah-Hartman

xen-blkfront: revoke foreign access for grants not mapped by the backend

2014-06-07T20:25:37+00:00

commit fbe363c476afe8ec992d3baf682670a4bd1b6ce6 upstream.

There's no need to keep the foreign access in a grant if it is not
persistently mapped by the backend. This allows us to free grants that
are not mapped by the backend, thus preventing blkfront from hoarding
all grants.

The main effect of this is that blkfront will only persistently map
the same grants as the backend, and it will always try to use grants
that are already mapped by the backend. Also the number of persistent
grants in blkfront is the same as in blkback (and is controlled by the
value in blkback).

Signed-off-by: Roger Pau Monné 
Reviewed-by: David Vrabel 
Acked-by: Matt Wilson 
Cc: Konrad Rzeszutek Wilk 
Cc: David Vrabel 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

rbd: fix error paths in rbd_img_request_fill()

2014-05-31T04:52:12+00:00

commit 42dd037c08c7cd6e3e9af7824b0c1d063f838885 upstream.

Doing rbd_obj_request_put() in rbd_img_request_fill() error paths is
not only insufficient, but also triggers an rbd_assert() in
rbd_obj_request_destroy():

    Assertion failure in rbd_obj_request_destroy() at line 1867:

    rbd_assert(obj_request->img_request == NULL);

rbd_img_obj_request_add() adds obj_requests to the img_request, the
opposite is rbd_img_obj_request_del().  Use it.

Fixes: http://tracker.ceph.com/issues/7327

Signed-off-by: Ilya Dryomov 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

floppy: don't write kernel-only members to FDRAWCMD ioctl output

2014-05-13T11:59:40+00:00

commit 2145e15e0557a01b9195d1c7199a1b92cb9be81f upstream.

Do not leak kernel-only floppy_raw_cmd structure members to userspace.
This includes the linked-list pointer and the pointer to the allocated
DMA space.

Signed-off-by: Matthew Daley 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

floppy: ignore kernel-only members in FDRAWCMD ioctl input

2014-05-13T11:59:40+00:00

commit ef87dbe7614341c2e7bfe8d32fcb7028cc97442c upstream.

Always clear out these floppy_raw_cmd struct members after copying the
entire structure from userspace so that the in-kernel version is always
valid and never left in an interdeterminate state.

Signed-off-by: Matthew Daley 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mtip32xx: Set queue bounce limit

2014-05-06T14:55:32+00:00

commit 1044b1bb9278f2e656a1a7b63dc24a59506540aa upstream.

We need to set the queue bounce limit during the device initialization to
prevent excessive bouncing on 32 bit architectures.

Signed-off-by: Felipe Franciosi 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

mm: close PageTail race

2014-04-03T19:01:05+00:00

commit 668f9abbd4334e6c29fa8acd71635c4f9101caa7 upstream.

Commit bf6bddf1924e ("mm: introduce compaction and migration for
ballooned pages") introduces page_count(page) into memory compaction
which dereferences page->first_page if PageTail(page).

This results in a very rare NULL pointer dereference on the
aforementioned page_count(page).  Indeed, anything that does
compound_head(), including page_count() is susceptible to racing with
prep_compound_page() and seeing a NULL or dangling page->first_page
pointer.

This patch uses Andrea's implementation of compound_trans_head() that
deals with such a race and makes it the default compound_head()
implementation.  This includes a read memory barrier that ensures that
if PageTail(head) is true that we return a head page that is neither
NULL nor dangling.  The patch then adds a store memory barrier to
prep_compound_page() to ensure page->first_page is set.

This is the safest way to ensure we see the head page that we are
expecting, PageTail(page) is already in the unlikely() path and the
memory barriers are unfortunately required.

Hugetlbfs is the exception, we don't enforce a store memory barrier
during init since no race is possible.

Signed-off-by: David Rientjes 
Cc: Holger Kiehl 
Cc: Christoph Lameter 
Cc: Rafael Aquini 
Cc: Vlastimil Babka 
Cc: Michal Hocko 
Cc: Mel Gorman 
Cc: Andrea Arcangeli 
Cc: Rik van Riel 
Cc: "Kirill A. Shutemov" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

xen-blkfront: handle backend CLOSED without CLOSING

2014-02-22T20:41:25+00:00

commit 3661371701e714f0cea4120f6a365340858fb4e4 upstream.

Backend drivers shouldn't transistion to CLOSED unless the frontend is
CLOSED.  If a backend does transition to CLOSED too soon then the
frontend may not see the CLOSING state and will not properly shutdown.

So, treat an unexpected backend CLOSED state the same as CLOSING.

Signed-off-by: David Vrabel 
Acked-by: Konrad Rzeszutek Wilk 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman

rbd: fix error handling from rbd_snap_name()

2014-01-09T20:24:26+00:00

commit da6a6b63978d45f9ae582d1f362f182012da3a22 upstream.

rbd_snap_name() calls rbd_dev_v{1,2}_snap_name() depending on the
format of the image. The format 1 version returns NULL on error, which
is handled by the caller. The format 2 version returns an ERR_PTR,
which the caller of rbd_snap_name() does not expect.

Fortunately this is unlikely to occur in practice because
rbd_snap_id_by_name() is called before rbd_snap_name(). This would hit
similar errors to rbd_snap_name() (like the snapshot not existing) and
return early, so rbd_snap_name() would not hit an error unless the
snapshot was removed between the two calls or memory was exhausted.

Use an ERR_PTR in rbd_dev_v1_snap_name() so that the specific error
can be propagated, and it is consistent with rbd_dev_v2_snap_name().
Handle the ERR_PTR in the only rbd_snap_name() caller.

Suggested-by: Alex Elder 
Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

rbd: ignore unmapped snapshots that no longer exist

2014-01-09T20:24:26+00:00

commit efadc98aab674153709cc357ba565f04e3164fcd upstream.

This prevents erroring out while adding a device when a snapshot
unrelated to the current mapping is deleted between reading the
snapshot context and reading the snapshot names. If the mapped
snapshot name is not found an error still occurs as usual.

Signed-off-by: Josh Durgin 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman