Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cciss: fix build for PROC_FS disabled
  block: fix amiga and atari floppy driver compile warning
  blk-throttle: Fix calculation of max number of WRITES to be dispatched
  ioprio: grab rcu_read_lock in sys_ioprio_{set,get}()
  xen/blkfront: cope with backend that fail empty BLKIF_OP_WRITE_BARRIER requests
  xen/blkfront: Implement FUA with BLKIF_OP_WRITE_BARRIER
  xen/blkfront: change blk_shadow.request to proper pointer
  xen/blkfront: map REQ_FLUSH into a full barrier
This commit is contained in:
Linus Torvalds 2010-11-27 07:17:50 +09:00
commit 78daa87b1d
6 changed files with 43 additions and 52 deletions

View file

@ -1341,7 +1341,7 @@ static struct request *set_next_request(void)
{
struct request_queue *q;
int cnt = FD_MAX_UNITS;
struct request *rq;
struct request *rq = NULL;
/* Find next queue we can dispatch from */
fdc_queue = fdc_queue + 1;

View file

@ -1399,7 +1399,7 @@ static struct request *set_next_request(void)
{
struct request_queue *q;
int old_pos = fdc_queue;
struct request *rq;
struct request *rq = NULL;
do {
q = unit[fdc_queue].disk->queue;

View file

@ -66,6 +66,7 @@ MODULE_VERSION("3.6.26");
MODULE_LICENSE("GPL");
static DEFINE_MUTEX(cciss_mutex);
static struct proc_dir_entry *proc_cciss;
#include "cciss_cmd.h"
#include "cciss.h"
@ -363,8 +364,6 @@ static const char *raid_label[] = { "0", "4", "1(1+0)", "5", "5+1", "ADG",
#define ENG_GIG_FACTOR (ENG_GIG/512)
#define ENGAGE_SCSI "engage scsi"
static struct proc_dir_entry *proc_cciss;
static void cciss_seq_show_header(struct seq_file *seq)
{
ctlr_info_t *h = seq->private;

View file

@ -65,7 +65,7 @@ enum blkif_state {
struct blk_shadow {
struct blkif_request req;
unsigned long request;
struct request *request;
unsigned long frame[BLKIF_MAX_SEGMENTS_PER_REQUEST];
};
@ -136,7 +136,7 @@ static void add_id_to_freelist(struct blkfront_info *info,
unsigned long id)
{
info->shadow[id].req.id = info->shadow_free;
info->shadow[id].request = 0;
info->shadow[id].request = NULL;
info->shadow_free = id;
}
@ -245,14 +245,11 @@ static int blkif_ioctl(struct block_device *bdev, fmode_t mode,
}
/*
* blkif_queue_request
* Generate a Xen blkfront IO request from a blk layer request. Reads
* and writes are handled as expected. Since we lack a loose flush
* request, we map flushes into a full ordered barrier.
*
* request block io
*
* id: for guest use only.
* operation: BLKIF_OP_{READ,WRITE,PROBE}
* buffer: buffer to read/write into. this should be a
* virtual address in the guest os.
* @req: a request struct
*/
static int blkif_queue_request(struct request *req)
{
@ -281,7 +278,7 @@ static int blkif_queue_request(struct request *req)
/* Fill out a communications ring structure. */
ring_req = RING_GET_REQUEST(&info->ring, info->ring.req_prod_pvt);
id = get_id_from_freelist(info);
info->shadow[id].request = (unsigned long)req;
info->shadow[id].request = req;
ring_req->id = id;
ring_req->sector_number = (blkif_sector_t)blk_rq_pos(req);
@ -290,6 +287,18 @@ static int blkif_queue_request(struct request *req)
ring_req->operation = rq_data_dir(req) ?
BLKIF_OP_WRITE : BLKIF_OP_READ;
if (req->cmd_flags & (REQ_FLUSH | REQ_FUA)) {
/*
* Ideally we could just do an unordered
* flush-to-disk, but all we have is a full write
* barrier at the moment. However, a barrier write is
* a superset of FUA, so we can implement it the same
* way. (It's also a FLUSH+FUA, since it is
* guaranteed ordered WRT previous writes.)
*/
ring_req->operation = BLKIF_OP_WRITE_BARRIER;
}
ring_req->nr_segments = blk_rq_map_sg(req->q, req, info->sg);
BUG_ON(ring_req->nr_segments > BLKIF_MAX_SEGMENTS_PER_REQUEST);
@ -634,7 +643,7 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
bret = RING_GET_RESPONSE(&info->ring, i);
id = bret->id;
req = (struct request *)info->shadow[id].request;
req = info->shadow[id].request;
blkif_completion(&info->shadow[id]);
@ -647,6 +656,16 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
printk(KERN_WARNING "blkfront: %s: write barrier op failed\n",
info->gd->disk_name);
error = -EOPNOTSUPP;
}
if (unlikely(bret->status == BLKIF_RSP_ERROR &&
info->shadow[id].req.nr_segments == 0)) {
printk(KERN_WARNING "blkfront: %s: empty write barrier op failed\n",
info->gd->disk_name);
error = -EOPNOTSUPP;
}
if (unlikely(error)) {
if (error == -EOPNOTSUPP)
error = 0;
info->feature_flush = 0;
xlvbd_flush(info);
}
@ -899,7 +918,7 @@ static int blkif_recover(struct blkfront_info *info)
/* Stage 3: Find pending requests and requeue them. */
for (i = 0; i < BLK_RING_SIZE; i++) {
/* Not in use? */
if (copy[i].request == 0)
if (!copy[i].request)
continue;
/* Grab a request slot and copy shadow state into it. */
@ -916,9 +935,7 @@ static int blkif_recover(struct blkfront_info *info)
req->seg[j].gref,
info->xbdev->otherend_id,
pfn_to_mfn(info->shadow[req->id].frame[j]),
rq_data_dir(
(struct request *)
info->shadow[req->id].request));
rq_data_dir(info->shadow[req->id].request));
info->shadow[req->id].req = *req;
info->ring.req_prod_pvt++;
@ -1067,14 +1084,8 @@ static void blkfront_connect(struct blkfront_info *info)
*/
info->feature_flush = 0;
/*
* The driver doesn't properly handled empty flushes, so
* lets disable barrier support for now.
*/
#if 0
if (!err && barrier)
info->feature_flush = REQ_FLUSH;
#endif
info->feature_flush = REQ_FLUSH | REQ_FUA;
err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size);
if (err) {