From e686307fdc84f249490e6c9da92fcb2424491f14 Mon Sep 17 00:00:00 2001
From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Fri, 17 Apr 2009 08:41:21 +0200
Subject: loop: use BIO list management functions

Now that the bio list management stuff is generic, convert loop to use
bio lists instead of its own private bio list implementation.

Cc:  Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 include/linux/bio.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'include/linux/bio.h')

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 7b214fd672a..f37ca8c726b 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -506,7 +506,7 @@ static inline int bio_has_data(struct bio *bio)
 }
 
 /*
- * BIO list managment for use by remapping drivers (e.g. DM or MD).
+ * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
  *
  * A bio_list anchors a singly-linked list of bios chained through the bi_next
  * member of the bio.  The bio_list also caches the last list member to allow
-- 
cgit v1.2.3-70-g09d2


From 2e46e8b27aa57c6bd34b3102b40ee4d0144b4fab Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 7 May 2009 22:24:41 +0900
Subject: block: drop request->hard_* and *nr_sectors

struct request has had a few different ways to represent some
properties of a request.  ->hard_* represent block layer's view of the
request progress (completion cursor) and the ones without the prefix
are supposed to represent the issue cursor and allowed to be updated
as necessary by the low level drivers.  The thing is that as block
layer supports partial completion, the two cursors really aren't
necessary and only cause confusion.  In addition, manual management of
request detail from low level drivers is cumbersome and error-prone at
the very least.

Another interesting duplicate fields are rq->[hard_]nr_sectors and
rq->{hard_cur|current}_nr_sectors against rq->data_len and
rq->bio->bi_size.  This is more convoluted than the hard_ case.

rq->[hard_]nr_sectors are initialized for requests with bio but
blk_rq_bytes() uses it only for !pc requests.  rq->data_len is
initialized for all request but blk_rq_bytes() uses it only for pc
requests.  This causes good amount of confusion throughout block layer
and its drivers and determining the request length has been a bit of
black magic which may or may not work depending on circumstances and
what the specific LLD is actually doing.

rq->{hard_cur|current}_nr_sectors represent the number of sectors in
the contiguous data area at the front.  This is mainly used by drivers
which transfers data by walking request segment-by-segment.  This
value always equals rq->bio->bi_size >> 9.  However, data length for
pc requests may not be multiple of 512 bytes and using this field
becomes a bit confusing.

In general, having multiple fields to represent the same property
leads only to confusion and subtle bugs.  With recent block low level
driver cleanups, no driver is accessing or manipulating these
duplicate fields directly.  Drop all the duplicates.  Now rq->sector
means the current sector, rq->data_len the current total length and
rq->bio->bi_size the current segment length.  Everything else is
defined in terms of these three and available only through accessors.

* blk_recalc_rq_sectors() is collapsed into blk_update_request() and
  now handles pc and fs requests equally other than rq->sector update.
  This means that now pc requests can use partial completion too (no
  in-kernel user yet tho).

* bio_cur_sectors() is replaced with bio_cur_bytes() as block layer
  now uses byte count as the primary data length.

* blk_rq_pos() is now guranteed to be always correct.  In-block users
  converted.

* blk_rq_bytes() is now guaranteed to be always valid as is
  blk_rq_sectors().  In-block users converted.

* blk_rq_sectors() is now guaranteed to equal blk_rq_bytes() >> 9.
  More convenient one is used.

* blk_rq_bytes() and blk_rq_cur_bytes() are now inlined and take const
  pointer to request.

[ Impact: API cleanup, single way to represent one property of a request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 block/blk-core.c         | 81 ++++++++++++++++++------------------------------
 block/blk-merge.c        | 36 +++------------------
 block/blk.h              |  1 -
 block/cfq-iosched.c      | 10 +++---
 include/linux/bio.h      |  6 ++--
 include/linux/blkdev.h   | 37 ++++++++++------------
 include/linux/elevator.h |  2 +-
 kernel/trace/blktrace.c  | 16 +++++-----
 8 files changed, 67 insertions(+), 122 deletions(-)

(limited to 'include/linux/bio.h')

diff --git a/block/blk-core.c b/block/blk-core.c
index 82dc20621c0..3596ca71909 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -127,7 +127,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
 	INIT_LIST_HEAD(&rq->timeout_list);
 	rq->cpu = -1;
 	rq->q = q;
-	rq->sector = rq->hard_sector = (sector_t) -1;
+	rq->sector = (sector_t) -1;
 	INIT_HLIST_NODE(&rq->hash);
 	RB_CLEAR_NODE(&rq->rb_node);
 	rq->cmd = rq->__cmd;
@@ -189,8 +189,7 @@ void blk_dump_rq_flags(struct request *rq, char *msg)
 	       (unsigned long long)blk_rq_pos(rq),
 	       blk_rq_sectors(rq), blk_rq_cur_sectors(rq));
 	printk(KERN_INFO "  bio %p, biotail %p, buffer %p, len %u\n",
-						rq->bio, rq->biotail,
-						rq->buffer, rq->data_len);
+	       rq->bio, rq->biotail, rq->buffer, blk_rq_bytes(rq));
 
 	if (blk_pc_request(rq)) {
 		printk(KERN_INFO "  cdb: ");
@@ -1096,7 +1095,7 @@ void init_request_from_bio(struct request *req, struct bio *bio)
 		req->cmd_flags |= REQ_NOIDLE;
 
 	req->errors = 0;
-	req->hard_sector = req->sector = bio->bi_sector;
+	req->sector = bio->bi_sector;
 	req->ioprio = bio_prio(bio);
 	blk_rq_bio_prep(req->q, req, bio);
 }
@@ -1113,14 +1112,13 @@ static inline bool queue_should_plug(struct request_queue *q)
 static int __make_request(struct request_queue *q, struct bio *bio)
 {
 	struct request *req;
-	int el_ret, nr_sectors;
+	int el_ret;
+	unsigned int bytes = bio->bi_size;
 	const unsigned short prio = bio_prio(bio);
 	const int sync = bio_sync(bio);
 	const int unplug = bio_unplug(bio);
 	int rw_flags;
 
-	nr_sectors = bio_sectors(bio);
-
 	/*
 	 * low level driver can indicate that it wants pages above a
 	 * certain limit bounced to low memory (ie for highmem, or even
@@ -1145,7 +1143,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 
 		req->biotail->bi_next = bio;
 		req->biotail = bio;
-		req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+		req->data_len += bytes;
 		req->ioprio = ioprio_best(req->ioprio, prio);
 		if (!blk_rq_cpu_valid(req))
 			req->cpu = bio->bi_comp_cpu;
@@ -1171,10 +1169,8 @@ static int __make_request(struct request_queue *q, struct bio *bio)
 		 * not touch req->buffer either...
 		 */
 		req->buffer = bio_data(bio);
-		req->current_nr_sectors = bio_cur_sectors(bio);
-		req->hard_cur_sectors = req->current_nr_sectors;
-		req->sector = req->hard_sector = bio->bi_sector;
-		req->nr_sectors = req->hard_nr_sectors += nr_sectors;
+		req->sector = bio->bi_sector;
+		req->data_len += bytes;
 		req->ioprio = ioprio_best(req->ioprio, prio);
 		if (!blk_rq_cpu_valid(req))
 			req->cpu = bio->bi_comp_cpu;
@@ -1557,7 +1553,7 @@ EXPORT_SYMBOL(submit_bio);
 int blk_rq_check_limits(struct request_queue *q, struct request *rq)
 {
 	if (blk_rq_sectors(rq) > q->max_sectors ||
-	    rq->data_len > q->max_hw_sectors << 9) {
+	    blk_rq_bytes(rq) > q->max_hw_sectors << 9) {
 		printk(KERN_ERR "%s: over max size limit.\n", __func__);
 		return -EIO;
 	}
@@ -1675,35 +1671,6 @@ static void blk_account_io_done(struct request *req)
 	}
 }
 
-/**
- * blk_rq_bytes - Returns bytes left to complete in the entire request
- * @rq: the request being processed
- **/
-unsigned int blk_rq_bytes(struct request *rq)
-{
-	if (blk_fs_request(rq))
-		return blk_rq_sectors(rq) << 9;
-
-	return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_bytes);
-
-/**
- * blk_rq_cur_bytes - Returns bytes left to complete in the current segment
- * @rq: the request being processed
- **/
-unsigned int blk_rq_cur_bytes(struct request *rq)
-{
-	if (blk_fs_request(rq))
-		return rq->current_nr_sectors << 9;
-
-	if (rq->bio)
-		return rq->bio->bi_size;
-
-	return rq->data_len;
-}
-EXPORT_SYMBOL_GPL(blk_rq_cur_bytes);
-
 struct request *elv_next_request(struct request_queue *q)
 {
 	struct request *rq;
@@ -1736,7 +1703,7 @@ struct request *elv_next_request(struct request_queue *q)
 		if (rq->cmd_flags & REQ_DONTPREP)
 			break;
 
-		if (q->dma_drain_size && rq->data_len) {
+		if (q->dma_drain_size && blk_rq_bytes(rq)) {
 			/*
 			 * make sure space for the drain appears we
 			 * know we can do this because max_hw_segments
@@ -1759,7 +1726,7 @@ struct request *elv_next_request(struct request_queue *q)
 			 * avoid resource deadlock.  REQ_STARTED will
 			 * prevent other fs requests from passing this one.
 			 */
-			if (q->dma_drain_size && rq->data_len &&
+			if (q->dma_drain_size && blk_rq_bytes(rq) &&
 			    !(rq->cmd_flags & REQ_DONTPREP)) {
 				/*
 				 * remove the space for the drain we added
@@ -1911,8 +1878,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 		 * can find how many bytes remain in the request
 		 * later.
 		 */
-		req->nr_sectors = req->hard_nr_sectors = 0;
-		req->current_nr_sectors = req->hard_cur_sectors = 0;
+		req->data_len = 0;
 		return false;
 	}
 
@@ -1926,8 +1892,25 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 		bio_iovec(bio)->bv_len -= nr_bytes;
 	}
 
-	blk_recalc_rq_sectors(req, total_bytes >> 9);
+	req->data_len -= total_bytes;
+	req->buffer = bio_data(req->bio);
+
+	/* update sector only for requests with clear definition of sector */
+	if (blk_fs_request(req) || blk_discard_rq(req))
+		req->sector += total_bytes >> 9;
+
+	/*
+	 * If total number of sectors is less than the first segment
+	 * size, something has gone terribly wrong.
+	 */
+	if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) {
+		printk(KERN_ERR "blk: request botched\n");
+		req->data_len = blk_rq_cur_bytes(req);
+	}
+
+	/* recalculate the number of segments */
 	blk_recalc_rq_segments(req);
+
 	return true;
 }
 EXPORT_SYMBOL_GPL(blk_update_request);
@@ -2049,11 +2032,7 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
 		rq->nr_phys_segments = bio_phys_segments(q, bio);
 		rq->buffer = bio_data(bio);
 	}
-	rq->current_nr_sectors = bio_cur_sectors(bio);
-	rq->hard_cur_sectors = rq->current_nr_sectors;
-	rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio);
 	rq->data_len = bio->bi_size;
-
 	rq->bio = rq->biotail = bio;
 
 	if (bio->bi_bdev)
diff --git a/block/blk-merge.c b/block/blk-merge.c
index bf62a87a9da..b8df66aef0f 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -9,35 +9,6 @@
 
 #include "blk.h"
 
-void blk_recalc_rq_sectors(struct request *rq, int nsect)
-{
-	if (blk_fs_request(rq) || blk_discard_rq(rq)) {
-		rq->hard_sector += nsect;
-		rq->hard_nr_sectors -= nsect;
-
-		/*
-		 * Move the I/O submission pointers ahead if required.
-		 */
-		if ((rq->nr_sectors >= rq->hard_nr_sectors) &&
-		    (rq->sector <= rq->hard_sector)) {
-			rq->sector = rq->hard_sector;
-			rq->nr_sectors = rq->hard_nr_sectors;
-			rq->hard_cur_sectors = bio_cur_sectors(rq->bio);
-			rq->current_nr_sectors = rq->hard_cur_sectors;
-			rq->buffer = bio_data(rq->bio);
-		}
-
-		/*
-		 * if total number of sectors is less than the first segment
-		 * size, something has gone terribly wrong
-		 */
-		if (rq->nr_sectors < rq->current_nr_sectors) {
-			printk(KERN_ERR "blk: request botched\n");
-			rq->nr_sectors = rq->current_nr_sectors;
-		}
-	}
-}
-
 static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
 					     struct bio *bio)
 {
@@ -199,8 +170,9 @@ new_segment:
 
 
 	if (unlikely(rq->cmd_flags & REQ_COPY_USER) &&
-	    (rq->data_len & q->dma_pad_mask)) {
-		unsigned int pad_len = (q->dma_pad_mask & ~rq->data_len) + 1;
+	    (blk_rq_bytes(rq) & q->dma_pad_mask)) {
+		unsigned int pad_len =
+			(q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1;
 
 		sg->length += pad_len;
 		rq->extra_len += pad_len;
@@ -398,7 +370,7 @@ static int attempt_merge(struct request_queue *q, struct request *req,
 	req->biotail->bi_next = next->bio;
 	req->biotail = next->biotail;
 
-	req->nr_sectors = req->hard_nr_sectors += next->hard_nr_sectors;
+	req->data_len += blk_rq_bytes(next);
 
 	elv_merge_requests(q, req, next);
 
diff --git a/block/blk.h b/block/blk.h
index 51115599df9..ab54529103c 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -101,7 +101,6 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req,
 int attempt_back_merge(struct request_queue *q, struct request *rq);
 int attempt_front_merge(struct request_queue *q, struct request *rq);
 void blk_recalc_rq_segments(struct request *rq);
-void blk_recalc_rq_sectors(struct request *rq, int nsect);
 
 void blk_queue_congestion_threshold(struct request_queue *q);
 
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index db4d990a66b..99ac4304d71 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -579,9 +579,9 @@ cfq_prio_tree_lookup(struct cfq_data *cfqd, struct rb_root *root,
 		 * Sort strictly based on sector.  Smallest to the left,
 		 * largest to the right.
 		 */
-		if (sector > cfqq->next_rq->sector)
+		if (sector > blk_rq_pos(cfqq->next_rq))
 			n = &(*p)->rb_right;
-		else if (sector < cfqq->next_rq->sector)
+		else if (sector < blk_rq_pos(cfqq->next_rq))
 			n = &(*p)->rb_left;
 		else
 			break;
@@ -611,8 +611,8 @@ static void cfq_prio_tree_add(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 		return;
 
 	cfqq->p_root = &cfqd->prio_trees[cfqq->org_ioprio];
-	__cfqq = cfq_prio_tree_lookup(cfqd, cfqq->p_root, cfqq->next_rq->sector,
-					 &parent, &p);
+	__cfqq = cfq_prio_tree_lookup(cfqd, cfqq->p_root,
+				      blk_rq_pos(cfqq->next_rq), &parent, &p);
 	if (!__cfqq) {
 		rb_link_node(&cfqq->p_node, parent, p);
 		rb_insert_color(&cfqq->p_node, cfqq->p_root);
@@ -996,7 +996,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd,
 	if (cfq_rq_close(cfqd, __cfqq->next_rq))
 		return __cfqq;
 
-	if (__cfqq->next_rq->sector < sector)
+	if (blk_rq_pos(__cfqq->next_rq) < sector)
 		node = rb_next(&__cfqq->p_node);
 	else
 		node = rb_prev(&__cfqq->p_node);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index f37ca8c726b..d30ec6f30dd 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -218,12 +218,12 @@ struct bio {
 #define bio_sectors(bio)	((bio)->bi_size >> 9)
 #define bio_empty_barrier(bio)	(bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio))
 
-static inline unsigned int bio_cur_sectors(struct bio *bio)
+static inline unsigned int bio_cur_bytes(struct bio *bio)
 {
 	if (bio->bi_vcnt)
-		return bio_iovec(bio)->bv_len >> 9;
+		return bio_iovec(bio)->bv_len;
 	else /* dataless requests such as discard */
-		return bio->bi_size >> 9;
+		return bio->bi_size;
 }
 
 static inline void *bio_data(struct bio *bio)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4e5f8559872..ce2bf5efa9b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -166,19 +166,8 @@ struct request {
 	enum rq_cmd_type_bits cmd_type;
 	unsigned long atomic_flags;
 
-	/* Maintain bio traversal state for part by part I/O submission.
-	 * hard_* are block layer internals, no driver should touch them!
-	 */
-
-	sector_t sector;		/* next sector to submit */
-	sector_t hard_sector;		/* next sector to complete */
-	unsigned long nr_sectors;	/* no. of sectors left to submit */
-	unsigned long hard_nr_sectors;	/* no. of sectors left to complete */
-	/* no. of sectors left to submit in the current segment */
-	unsigned int current_nr_sectors;
-
-	/* no. of sectors left to complete in the current segment */
-	unsigned int hard_cur_sectors;
+	sector_t sector;	/* sector cursor */
+	unsigned int data_len;	/* total data len, don't access directly */
 
 	struct bio *bio;
 	struct bio *biotail;
@@ -226,7 +215,6 @@ struct request {
 	unsigned char __cmd[BLK_MAX_CDB];
 	unsigned char *cmd;
 
-	unsigned int data_len;
 	unsigned int extra_len;	/* length of alignment and padding */
 	unsigned int sense_len;
 	unsigned int resid_len;	/* residual count */
@@ -840,20 +828,27 @@ extern void blkdev_dequeue_request(struct request *req);
  */
 static inline sector_t blk_rq_pos(const struct request *rq)
 {
-	return rq->hard_sector;
+	return rq->sector;
+}
+
+static inline unsigned int blk_rq_bytes(const struct request *rq)
+{
+	return rq->data_len;
 }
 
-extern unsigned int blk_rq_bytes(struct request *rq);
-extern unsigned int blk_rq_cur_bytes(struct request *rq);
+static inline int blk_rq_cur_bytes(const struct request *rq)
+{
+	return rq->bio ? bio_cur_bytes(rq->bio) : 0;
+}
 
 static inline unsigned int blk_rq_sectors(const struct request *rq)
 {
-	return rq->hard_nr_sectors;
+	return blk_rq_bytes(rq) >> 9;
 }
 
 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
 {
-	return rq->hard_cur_sectors;
+	return blk_rq_cur_bytes(rq) >> 9;
 }
 
 /*
@@ -928,7 +923,7 @@ static inline void blk_end_request_all(struct request *rq, int error)
  */
 static inline bool blk_end_request_cur(struct request *rq, int error)
 {
-	return blk_end_request(rq, error, rq->hard_cur_sectors << 9);
+	return blk_end_request(rq, error, blk_rq_cur_bytes(rq));
 }
 
 /**
@@ -981,7 +976,7 @@ static inline void __blk_end_request_all(struct request *rq, int error)
  */
 static inline bool __blk_end_request_cur(struct request *rq, int error)
 {
-	return __blk_end_request(rq, error, rq->hard_cur_sectors << 9);
+	return __blk_end_request(rq, error, blk_rq_cur_bytes(rq));
 }
 
 extern void blk_complete_request(struct request *);
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index c59b769f62b..4e462878c9c 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -171,7 +171,7 @@ enum {
 	ELV_MQUEUE_MUST,
 };
 
-#define rq_end_sector(rq)	((rq)->sector + (rq)->nr_sectors)
+#define rq_end_sector(rq)	(blk_rq_pos(rq) + blk_rq_sectors(rq))
 #define rb_entry_rq(node)	rb_entry((node), struct request, rb_node)
 
 /*
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 42f1c11e754..5708a14bee5 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -642,12 +642,12 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
 
 	if (blk_pc_request(rq)) {
 		what |= BLK_TC_ACT(BLK_TC_PC);
-		__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors,
-				rq->cmd_len, rq->cmd);
+		__blk_add_trace(bt, 0, blk_rq_bytes(rq), rw,
+				what, rq->errors, rq->cmd_len, rq->cmd);
 	} else  {
 		what |= BLK_TC_ACT(BLK_TC_FS);
-		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_sectors(rq) << 9,
-				rw, what, rq->errors, 0, NULL);
+		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw,
+				what, rq->errors, 0, NULL);
 	}
 }
 
@@ -854,11 +854,11 @@ void blk_add_driver_data(struct request_queue *q,
 		return;
 
 	if (blk_pc_request(rq))
-		__blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA,
-				rq->errors, len, data);
+		__blk_add_trace(bt, 0, blk_rq_bytes(rq), 0,
+				BLK_TA_DRV_DATA, rq->errors, len, data);
 	else
-		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_sectors(rq) << 9,
-				0, BLK_TA_DRV_DATA, rq->errors, len, data);
+		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), 0,
+				BLK_TA_DRV_DATA, rq->errors, len, data);
 }
 EXPORT_SYMBOL_GPL(blk_add_driver_data);
 
-- 
cgit v1.2.3-70-g09d2


From ae03bf639a5027d27270123f5f6e3ee6a412781d Mon Sep 17 00:00:00 2001
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Date: Fri, 22 May 2009 17:17:50 -0400
Subject: block: Use accessor functions for queue limits

Convert all external users of queue limits to using wrapper functions
instead of poking the request queue variables directly.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 block/blk-barrier.c            |  8 ++++----
 block/blk-core.c               | 16 ++++++++--------
 block/blk-map.c                |  4 ++--
 block/blk-merge.c              | 27 ++++++++++++++-------------
 block/blk-settings.c           | 15 ++++++++++++---
 block/blk-sysfs.c              |  8 ++++----
 block/compat_ioctl.c           |  2 +-
 block/ioctl.c                  | 10 +++++-----
 block/scsi_ioctl.c             |  8 ++++----
 drivers/block/pktcdvd.c        |  6 ++++--
 drivers/cdrom/cdrom.c          |  4 ++--
 drivers/md/dm-table.c          | 28 ++++++++++++++--------------
 drivers/md/linear.c            |  2 +-
 drivers/md/multipath.c         |  4 ++--
 drivers/md/raid0.c             |  2 +-
 drivers/md/raid1.c             |  4 ++--
 drivers/md/raid10.c            |  8 ++++----
 drivers/md/raid5.c             |  4 ++--
 drivers/scsi/sg.c              | 15 ++++++++-------
 drivers/scsi/st.c              |  4 ++--
 drivers/usb/storage/scsiglue.c |  4 ++--
 fs/bio.c                       | 19 ++++++++++---------
 include/linux/bio.h            |  2 +-
 include/linux/blkdev.h         | 36 ++++++++++++++++++++++++++++++++++++
 mm/bounce.c                    |  4 ++--
 25 files changed, 147 insertions(+), 97 deletions(-)

(limited to 'include/linux/bio.h')

diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 0d98054cdbd..30022b4e2f6 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -388,10 +388,10 @@ int blkdev_issue_discard(struct block_device *bdev,
 
 		bio->bi_sector = sector;
 
-		if (nr_sects > q->max_hw_sectors) {
-			bio->bi_size = q->max_hw_sectors << 9;
-			nr_sects -= q->max_hw_sectors;
-			sector += q->max_hw_sectors;
+		if (nr_sects > queue_max_hw_sectors(q)) {
+			bio->bi_size = queue_max_hw_sectors(q) << 9;
+			nr_sects -= queue_max_hw_sectors(q);
+			sector += queue_max_hw_sectors(q);
 		} else {
 			bio->bi_size = nr_sects << 9;
 			nr_sects = 0;
diff --git a/block/blk-core.c b/block/blk-core.c
index 59c4af52311..7a4c40184a6 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1437,11 +1437,11 @@ static inline void __generic_make_request(struct bio *bio)
 			goto end_io;
 		}
 
-		if (unlikely(nr_sectors > q->max_hw_sectors)) {
+		if (unlikely(nr_sectors > queue_max_hw_sectors(q))) {
 			printk(KERN_ERR "bio too big device %s (%u > %u)\n",
-				bdevname(bio->bi_bdev, b),
-				bio_sectors(bio),
-				q->max_hw_sectors);
+			       bdevname(bio->bi_bdev, b),
+			       bio_sectors(bio),
+			       queue_max_hw_sectors(q));
 			goto end_io;
 		}
 
@@ -1608,8 +1608,8 @@ EXPORT_SYMBOL(submit_bio);
  */
 int blk_rq_check_limits(struct request_queue *q, struct request *rq)
 {
-	if (blk_rq_sectors(rq) > q->max_sectors ||
-	    blk_rq_bytes(rq) > q->max_hw_sectors << 9) {
+	if (blk_rq_sectors(rq) > queue_max_sectors(q) ||
+	    blk_rq_bytes(rq) > queue_max_hw_sectors(q) << 9) {
 		printk(KERN_ERR "%s: over max size limit.\n", __func__);
 		return -EIO;
 	}
@@ -1621,8 +1621,8 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq)
 	 * limitation.
 	 */
 	blk_recalc_rq_segments(rq);
-	if (rq->nr_phys_segments > q->max_phys_segments ||
-	    rq->nr_phys_segments > q->max_hw_segments) {
+	if (rq->nr_phys_segments > queue_max_phys_segments(q) ||
+	    rq->nr_phys_segments > queue_max_hw_segments(q)) {
 		printk(KERN_ERR "%s: over max segments limit.\n", __func__);
 		return -EIO;
 	}
diff --git a/block/blk-map.c b/block/blk-map.c
index ef2492adca7..9083cf0180c 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -115,7 +115,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 	struct bio *bio = NULL;
 	int ret;
 
-	if (len > (q->max_hw_sectors << 9))
+	if (len > (queue_max_hw_sectors(q) << 9))
 		return -EINVAL;
 	if (!len)
 		return -EINVAL;
@@ -292,7 +292,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
 	struct bio *bio;
 	int ret;
 
-	if (len > (q->max_hw_sectors << 9))
+	if (len > (queue_max_hw_sectors(q) << 9))
 		return -EINVAL;
 	if (!len || !kbuf)
 		return -EINVAL;
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 4974dd5767e..39ce64432ba 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -32,11 +32,12 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
 			 * never considered part of another segment, since that
 			 * might change with the bounce page.
 			 */
-			high = page_to_pfn(bv->bv_page) > q->bounce_pfn;
+			high = page_to_pfn(bv->bv_page) > queue_bounce_pfn(q);
 			if (high || highprv)
 				goto new_segment;
 			if (cluster) {
-				if (seg_size + bv->bv_len > q->max_segment_size)
+				if (seg_size + bv->bv_len
+				    > queue_max_segment_size(q))
 					goto new_segment;
 				if (!BIOVEC_PHYS_MERGEABLE(bvprv, bv))
 					goto new_segment;
@@ -91,7 +92,7 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
 		return 0;
 
 	if (bio->bi_seg_back_size + nxt->bi_seg_front_size >
-	    q->max_segment_size)
+	    queue_max_segment_size(q))
 		return 0;
 
 	if (!bio_has_data(bio))
@@ -134,7 +135,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
 		int nbytes = bvec->bv_len;
 
 		if (bvprv && cluster) {
-			if (sg->length + nbytes > q->max_segment_size)
+			if (sg->length + nbytes > queue_max_segment_size(q))
 				goto new_segment;
 
 			if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
@@ -205,8 +206,8 @@ static inline int ll_new_hw_segment(struct request_queue *q,
 {
 	int nr_phys_segs = bio_phys_segments(q, bio);
 
-	if (req->nr_phys_segments + nr_phys_segs > q->max_hw_segments
-	    || req->nr_phys_segments + nr_phys_segs > q->max_phys_segments) {
+	if (req->nr_phys_segments + nr_phys_segs > queue_max_hw_segments(q) ||
+	    req->nr_phys_segments + nr_phys_segs > queue_max_phys_segments(q)) {
 		req->cmd_flags |= REQ_NOMERGE;
 		if (req == q->last_merge)
 			q->last_merge = NULL;
@@ -227,9 +228,9 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req,
 	unsigned short max_sectors;
 
 	if (unlikely(blk_pc_request(req)))
-		max_sectors = q->max_hw_sectors;
+		max_sectors = queue_max_hw_sectors(q);
 	else
-		max_sectors = q->max_sectors;
+		max_sectors = queue_max_sectors(q);
 
 	if (blk_rq_sectors(req) + bio_sectors(bio) > max_sectors) {
 		req->cmd_flags |= REQ_NOMERGE;
@@ -251,9 +252,9 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req,
 	unsigned short max_sectors;
 
 	if (unlikely(blk_pc_request(req)))
-		max_sectors = q->max_hw_sectors;
+		max_sectors = queue_max_hw_sectors(q);
 	else
-		max_sectors = q->max_sectors;
+		max_sectors = queue_max_sectors(q);
 
 
 	if (blk_rq_sectors(req) + bio_sectors(bio) > max_sectors) {
@@ -287,7 +288,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
 	/*
 	 * Will it become too large?
 	 */
-	if ((blk_rq_sectors(req) + blk_rq_sectors(next)) > q->max_sectors)
+	if ((blk_rq_sectors(req) + blk_rq_sectors(next)) > queue_max_sectors(q))
 		return 0;
 
 	total_phys_segments = req->nr_phys_segments + next->nr_phys_segments;
@@ -299,10 +300,10 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
 		total_phys_segments--;
 	}
 
-	if (total_phys_segments > q->max_phys_segments)
+	if (total_phys_segments > queue_max_phys_segments(q))
 		return 0;
 
-	if (total_phys_segments > q->max_hw_segments)
+	if (total_phys_segments > queue_max_hw_segments(q))
 		return 0;
 
 	/* Merge is OK... */
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 15c3164537b..0b32f984eed 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -219,6 +219,15 @@ void blk_queue_max_sectors(struct request_queue *q, unsigned int max_sectors)
 }
 EXPORT_SYMBOL(blk_queue_max_sectors);
 
+void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_sectors)
+{
+	if (BLK_DEF_MAX_SECTORS > max_sectors)
+		q->max_hw_sectors = BLK_DEF_MAX_SECTORS;
+	else
+		q->max_hw_sectors = max_sectors;
+}
+EXPORT_SYMBOL(blk_queue_max_hw_sectors);
+
 /**
  * blk_queue_max_phys_segments - set max phys segments for a request for this queue
  * @q:  the request queue for the device
@@ -395,11 +404,11 @@ int blk_queue_dma_drain(struct request_queue *q,
 			       dma_drain_needed_fn *dma_drain_needed,
 			       void *buf, unsigned int size)
 {
-	if (q->max_hw_segments < 2 || q->max_phys_segments < 2)
+	if (queue_max_hw_segments(q) < 2 || queue_max_phys_segments(q) < 2)
 		return -EINVAL;
 	/* make room for appending the drain */
-	--q->max_hw_segments;
-	--q->max_phys_segments;
+	blk_queue_max_hw_segments(q, queue_max_hw_segments(q) - 1);
+	blk_queue_max_phys_segments(q, queue_max_phys_segments(q) - 1);
 	q->dma_drain_needed = dma_drain_needed;
 	q->dma_drain_buffer = buf;
 	q->dma_drain_size = size;
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 13d38b7e4d0..142a4acddd4 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -95,7 +95,7 @@ queue_ra_store(struct request_queue *q, const char *page, size_t count)
 
 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
 {
-	int max_sectors_kb = q->max_sectors >> 1;
+	int max_sectors_kb = queue_max_sectors(q) >> 1;
 
 	return queue_var_show(max_sectors_kb, (page));
 }
@@ -109,7 +109,7 @@ static ssize_t
 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 {
 	unsigned long max_sectors_kb,
-			max_hw_sectors_kb = q->max_hw_sectors >> 1,
+		max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
 			page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
 	ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
 
@@ -117,7 +117,7 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 		return -EINVAL;
 
 	spin_lock_irq(q->queue_lock);
-	q->max_sectors = max_sectors_kb << 1;
+	blk_queue_max_sectors(q, max_sectors_kb << 1);
 	spin_unlock_irq(q->queue_lock);
 
 	return ret;
@@ -125,7 +125,7 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
 
 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
 {
-	int max_hw_sectors_kb = q->max_hw_sectors >> 1;
+	int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
 
 	return queue_var_show(max_hw_sectors_kb, (page));
 }
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 9eaa1940273..df18a156d01 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -766,7 +766,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		return compat_put_int(arg, bdev_logical_block_size(bdev));
 	case BLKSECTGET:
 		return compat_put_ushort(arg,
-					 bdev_get_queue(bdev)->max_sectors);
+					 queue_max_sectors(bdev_get_queue(bdev)));
 	case BLKRASET: /* compatible, but no compat_ptr (!) */
 	case BLKFRASET:
 		if (!capable(CAP_SYS_ADMIN))
diff --git a/block/ioctl.c b/block/ioctl.c
index 7aa97f65da8..500e4c73cc5 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -152,10 +152,10 @@ static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
 		bio->bi_private = &wait;
 		bio->bi_sector = start;
 
-		if (len > q->max_hw_sectors) {
-			bio->bi_size = q->max_hw_sectors << 9;
-			len -= q->max_hw_sectors;
-			start += q->max_hw_sectors;
+		if (len > queue_max_hw_sectors(q)) {
+			bio->bi_size = queue_max_hw_sectors(q) << 9;
+			len -= queue_max_hw_sectors(q);
+			start += queue_max_hw_sectors(q);
 		} else {
 			bio->bi_size = len << 9;
 			len = 0;
@@ -313,7 +313,7 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	case BLKSSZGET: /* get block device hardware sector size */
 		return put_int(arg, bdev_logical_block_size(bdev));
 	case BLKSECTGET:
-		return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
+		return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev)));
 	case BLKRASET:
 	case BLKFRASET:
 		if(!capable(CAP_SYS_ADMIN))
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index a9670dd4b5d..5f8e798ede4 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -75,7 +75,7 @@ static int sg_set_timeout(struct request_queue *q, int __user *p)
 
 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
 {
-	unsigned val = min(q->sg_reserved_size, q->max_sectors << 9);
+	unsigned val = min(q->sg_reserved_size, queue_max_sectors(q) << 9);
 
 	return put_user(val, p);
 }
@@ -89,8 +89,8 @@ static int sg_set_reserved_size(struct request_queue *q, int __user *p)
 
 	if (size < 0)
 		return -EINVAL;
-	if (size > (q->max_sectors << 9))
-		size = q->max_sectors << 9;
+	if (size > (queue_max_sectors(q) << 9))
+		size = queue_max_sectors(q) << 9;
 
 	q->sg_reserved_size = size;
 	return 0;
@@ -264,7 +264,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 	if (hdr->cmd_len > BLK_MAX_CDB)
 		return -EINVAL;
 
-	if (hdr->dxfer_len > (q->max_hw_sectors << 9))
+	if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 		return -EIO;
 
 	if (hdr->dxfer_len)
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 293f5858921..d57f1175948 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -991,13 +991,15 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
  */
 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 {
-	if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
+	if ((pd->settings.size << 9) / CD_FRAMESIZE
+	    <= queue_max_phys_segments(q)) {
 		/*
 		 * The cdrom device can handle one segment/frame
 		 */
 		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 		return 0;
-	} else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
+	} else if ((pd->settings.size << 9) / PAGE_SIZE
+		   <= queue_max_phys_segments(q)) {
 		/*
 		 * We can handle this case at the expense of some extra memory
 		 * copies during write operations
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index cceace61ef2..71d1b9bab70 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2101,8 +2101,8 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf,
 		nr = nframes;
 		if (cdi->cdda_method == CDDA_BPC_SINGLE)
 			nr = 1;
-		if (nr * CD_FRAMESIZE_RAW > (q->max_sectors << 9))
-			nr = (q->max_sectors << 9) / CD_FRAMESIZE_RAW;
+		if (nr * CD_FRAMESIZE_RAW > (queue_max_sectors(q) << 9))
+			nr = (queue_max_sectors(q) << 9) / CD_FRAMESIZE_RAW;
 
 		len = nr * CD_FRAMESIZE_RAW;
 
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 65e2d975985..e9a73bb242b 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -510,7 +510,7 @@ void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
 	 *        combine_restrictions_low()
 	 */
 	rs->max_sectors =
-		min_not_zero(rs->max_sectors, q->max_sectors);
+		min_not_zero(rs->max_sectors, queue_max_sectors(q));
 
 	/*
 	 * Check if merge fn is supported.
@@ -525,25 +525,25 @@ void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
 
 	rs->max_phys_segments =
 		min_not_zero(rs->max_phys_segments,
-			     q->max_phys_segments);
+			     queue_max_phys_segments(q));
 
 	rs->max_hw_segments =
-		min_not_zero(rs->max_hw_segments, q->max_hw_segments);
+		min_not_zero(rs->max_hw_segments, queue_max_hw_segments(q));
 
 	rs->logical_block_size = max(rs->logical_block_size,
 				     queue_logical_block_size(q));
 
 	rs->max_segment_size =
-		min_not_zero(rs->max_segment_size, q->max_segment_size);
+		min_not_zero(rs->max_segment_size, queue_max_segment_size(q));
 
 	rs->max_hw_sectors =
-		min_not_zero(rs->max_hw_sectors, q->max_hw_sectors);
+		min_not_zero(rs->max_hw_sectors, queue_max_hw_sectors(q));
 
 	rs->seg_boundary_mask =
 		min_not_zero(rs->seg_boundary_mask,
-			     q->seg_boundary_mask);
+			     queue_segment_boundary(q));
 
-	rs->bounce_pfn = min_not_zero(rs->bounce_pfn, q->bounce_pfn);
+	rs->bounce_pfn = min_not_zero(rs->bounce_pfn, queue_bounce_pfn(q));
 
 	rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
 }
@@ -914,13 +914,13 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q)
 	 * restrictions.
 	 */
 	blk_queue_max_sectors(q, t->limits.max_sectors);
-	q->max_phys_segments = t->limits.max_phys_segments;
-	q->max_hw_segments = t->limits.max_hw_segments;
-	q->logical_block_size = t->limits.logical_block_size;
-	q->max_segment_size = t->limits.max_segment_size;
-	q->max_hw_sectors = t->limits.max_hw_sectors;
-	q->seg_boundary_mask = t->limits.seg_boundary_mask;
-	q->bounce_pfn = t->limits.bounce_pfn;
+	blk_queue_max_phys_segments(q, t->limits.max_phys_segments);
+	blk_queue_max_hw_segments(q, t->limits.max_hw_segments);
+	blk_queue_logical_block_size(q, t->limits.logical_block_size);
+	blk_queue_max_segment_size(q, t->limits.max_segment_size);
+	blk_queue_max_hw_sectors(q, t->limits.max_hw_sectors);
+	blk_queue_segment_boundary(q, t->limits.seg_boundary_mask);
+	blk_queue_bounce_limit(q, t->limits.bounce_pfn);
 
 	if (t->limits.no_cluster)
 		queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q);
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 7a36e38393a..64f1f3e046e 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -146,7 +146,7 @@ static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks)
 		 * a one page request is never in violation.
 		 */
 		if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-		    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
 			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		disk->num_sectors = rdev->sectors;
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 41ced0cbe82..4ee31aa13c4 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -303,7 +303,7 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 		 * merge_bvec_fn will be involved in multipath.)
 		 */
 			if (q->merge_bvec_fn &&
-			    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+			    queue_max_sectors(q) > (PAGE_SIZE>>9))
 				blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 			conf->working_disks++;
@@ -467,7 +467,7 @@ static int multipath_run (mddev_t *mddev)
 		 * violating it, not that we ever expect a device with
 		 * a merge_bvec_fn to be involved in multipath */
 		if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-		    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
 			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		if (!test_bit(Faulty, &rdev->flags))
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index c08d7559be5..925507e7d67 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -144,7 +144,7 @@ static int create_strip_zones (mddev_t *mddev)
 		 */
 
 		if (rdev1->bdev->bd_disk->queue->merge_bvec_fn &&
-		    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
 			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		if (!smallest || (rdev1->sectors < smallest->sectors))
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 36df9109cde..e23758b4a34 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1130,7 +1130,7 @@ static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 			 * a one page request is never in violation.
 			 */
 			if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-			    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+			    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
 				blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 			p->head_position = 0;
@@ -1996,7 +1996,7 @@ static int run(mddev_t *mddev)
 		 * a one page request is never in violation.
 		 */
 		if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-		    mddev->queue->max_sectors > (PAGE_SIZE>>9))
+		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
 			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		disk->head_position = 0;
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 499620afb44..750550c1166 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1158,8 +1158,8 @@ static int raid10_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 			 * a one page request is never in violation.
 			 */
 			if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-			    mddev->queue->max_sectors > (PAGE_SIZE>>9))
-				mddev->queue->max_sectors = (PAGE_SIZE>>9);
+			    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
+				blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 			p->head_position = 0;
 			rdev->raid_disk = mirror;
@@ -2145,8 +2145,8 @@ static int run(mddev_t *mddev)
 		 * a one page request is never in violation.
 		 */
 		if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-		    mddev->queue->max_sectors > (PAGE_SIZE>>9))
-			mddev->queue->max_sectors = (PAGE_SIZE>>9);
+		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
+			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		disk->head_position = 0;
 	}
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 4616bc3a6e7..7970dc8c522 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3463,10 +3463,10 @@ static int bio_fits_rdev(struct bio *bi)
 {
 	struct request_queue *q = bdev_get_queue(bi->bi_bdev);
 
-	if ((bi->bi_size>>9) > q->max_sectors)
+	if ((bi->bi_size>>9) > queue_max_sectors(q))
 		return 0;
 	blk_recount_segments(q, bi);
-	if (bi->bi_phys_segments > q->max_phys_segments)
+	if (bi->bi_phys_segments > queue_max_phys_segments(q))
 		return 0;
 
 	if (q->merge_bvec_fn)
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 0fc2c0ae769..9bd407fa98e 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -289,8 +289,8 @@ sg_open(struct inode *inode, struct file *filp)
 	if (list_empty(&sdp->sfds)) {	/* no existing opens on this device */
 		sdp->sgdebug = 0;
 		q = sdp->device->request_queue;
-		sdp->sg_tablesize = min(q->max_hw_segments,
-					q->max_phys_segments);
+		sdp->sg_tablesize = min(queue_max_hw_segments(q),
+					queue_max_phys_segments(q));
 	}
 	if ((sfp = sg_add_sfp(sdp, dev)))
 		filp->private_data = sfp;
@@ -909,7 +909,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
                 if (val < 0)
                         return -EINVAL;
 		val = min_t(int, val,
-				sdp->device->request_queue->max_sectors * 512);
+			    queue_max_sectors(sdp->device->request_queue) * 512);
 		if (val != sfp->reserve.bufflen) {
 			if (sg_res_in_use(sfp) || sfp->mmap_called)
 				return -EBUSY;
@@ -919,7 +919,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
 		return 0;
 	case SG_GET_RESERVED_SIZE:
 		val = min_t(int, sfp->reserve.bufflen,
-				sdp->device->request_queue->max_sectors * 512);
+			    queue_max_sectors(sdp->device->request_queue) * 512);
 		return put_user(val, ip);
 	case SG_SET_COMMAND_Q:
 		result = get_user(val, ip);
@@ -1059,7 +1059,7 @@ sg_ioctl(struct inode *inode, struct file *filp,
 			return -ENODEV;
 		return scsi_ioctl(sdp->device, cmd_in, p);
 	case BLKSECTGET:
-		return put_user(sdp->device->request_queue->max_sectors * 512,
+		return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
 				ip);
 	case BLKTRACESETUP:
 		return blk_trace_setup(sdp->device->request_queue,
@@ -1377,7 +1377,8 @@ static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
 	sdp->device = scsidp;
 	INIT_LIST_HEAD(&sdp->sfds);
 	init_waitqueue_head(&sdp->o_excl_wait);
-	sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
+	sdp->sg_tablesize = min(queue_max_hw_segments(q),
+				queue_max_phys_segments(q));
 	sdp->index = k;
 	kref_init(&sdp->d_ref);
 
@@ -2055,7 +2056,7 @@ sg_add_sfp(Sg_device * sdp, int dev)
 		sg_big_buff = def_reserved_size;
 
 	bufflen = min_t(int, sg_big_buff,
-			sdp->device->request_queue->max_sectors * 512);
+			queue_max_sectors(sdp->device->request_queue) * 512);
 	sg_build_reserve(sfp, bufflen);
 	SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
 			   sfp->reserve.bufflen, sfp->reserve.k_use_sg));
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 8681b708344..89bd438e1fe 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -3983,8 +3983,8 @@ static int st_probe(struct device *dev)
 		return -ENODEV;
 	}
 
-	i = min(SDp->request_queue->max_hw_segments,
-		SDp->request_queue->max_phys_segments);
+	i = min(queue_max_hw_segments(SDp->request_queue),
+		queue_max_phys_segments(SDp->request_queue));
 	if (st_max_sg_segs < i)
 		i = st_max_sg_segs;
 	buffer = new_tape_buffer((SDp->host)->unchecked_isa_dma, i);
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 4ca3b586064..cfa26d56ce6 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -132,7 +132,7 @@ static int slave_configure(struct scsi_device *sdev)
 
 		if (us->fflags & US_FL_MAX_SECTORS_MIN)
 			max_sectors = PAGE_CACHE_SIZE >> 9;
-		if (sdev->request_queue->max_sectors > max_sectors)
+		if (queue_max_sectors(sdev->request_queue) > max_sectors)
 			blk_queue_max_sectors(sdev->request_queue,
 					      max_sectors);
 	} else if (sdev->type == TYPE_TAPE) {
@@ -483,7 +483,7 @@ static ssize_t show_max_sectors(struct device *dev, struct device_attribute *att
 {
 	struct scsi_device *sdev = to_scsi_device(dev);
 
-	return sprintf(buf, "%u\n", sdev->request_queue->max_sectors);
+	return sprintf(buf, "%u\n", queue_max_sectors(sdev->request_queue));
 }
 
 /* Input routine for the sysfs max_sectors file */
diff --git a/fs/bio.c b/fs/bio.c
index 4445c382173..ab423a1024a 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -499,11 +499,11 @@ int bio_get_nr_vecs(struct block_device *bdev)
 	struct request_queue *q = bdev_get_queue(bdev);
 	int nr_pages;
 
-	nr_pages = ((q->max_sectors << 9) + PAGE_SIZE - 1) >> PAGE_SHIFT;
-	if (nr_pages > q->max_phys_segments)
-		nr_pages = q->max_phys_segments;
-	if (nr_pages > q->max_hw_segments)
-		nr_pages = q->max_hw_segments;
+	nr_pages = ((queue_max_sectors(q) << 9) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	if (nr_pages > queue_max_phys_segments(q))
+		nr_pages = queue_max_phys_segments(q);
+	if (nr_pages > queue_max_hw_segments(q))
+		nr_pages = queue_max_hw_segments(q);
 
 	return nr_pages;
 }
@@ -562,8 +562,8 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 	 * make this too complex.
 	 */
 
-	while (bio->bi_phys_segments >= q->max_phys_segments
-	       || bio->bi_phys_segments >= q->max_hw_segments) {
+	while (bio->bi_phys_segments >= queue_max_phys_segments(q)
+	       || bio->bi_phys_segments >= queue_max_hw_segments(q)) {
 
 		if (retried_segments)
 			return 0;
@@ -634,7 +634,8 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page,
 		    unsigned int len, unsigned int offset)
 {
-	return __bio_add_page(q, bio, page, len, offset, q->max_hw_sectors);
+	return __bio_add_page(q, bio, page, len, offset,
+			      queue_max_hw_sectors(q));
 }
 
 /**
@@ -654,7 +655,7 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
 		 unsigned int offset)
 {
 	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
-	return __bio_add_page(q, bio, page, len, offset, q->max_sectors);
+	return __bio_add_page(q, bio, page, len, offset, queue_max_sectors(q));
 }
 
 struct bio_map_data {
diff --git a/include/linux/bio.h b/include/linux/bio.h
index d30ec6f30dd..12737be5860 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -279,7 +279,7 @@ static inline int bio_has_allocated_vec(struct bio *bio)
 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
 	(((addr1) | (mask)) == (((addr2) - 1) | (mask)))
 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
-	__BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, (q)->seg_boundary_mask)
+	__BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
 #define BIO_SEG_BOUNDARY(q, b1, b2) \
 	BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 872b78b7a10..29b48f7b4ba 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -898,6 +898,7 @@ extern void blk_cleanup_queue(struct request_queue *);
 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
 extern void blk_queue_bounce_limit(struct request_queue *, u64);
 extern void blk_queue_max_sectors(struct request_queue *, unsigned int);
+extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
 extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short);
 extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short);
 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
@@ -988,6 +989,41 @@ extern void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter);
 
 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
 
+static inline unsigned long queue_bounce_pfn(struct request_queue *q)
+{
+	return q->bounce_pfn;
+}
+
+static inline unsigned long queue_segment_boundary(struct request_queue *q)
+{
+	return q->seg_boundary_mask;
+}
+
+static inline unsigned int queue_max_sectors(struct request_queue *q)
+{
+	return q->max_sectors;
+}
+
+static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
+{
+	return q->max_hw_sectors;
+}
+
+static inline unsigned short queue_max_hw_segments(struct request_queue *q)
+{
+	return q->max_hw_segments;
+}
+
+static inline unsigned short queue_max_phys_segments(struct request_queue *q)
+{
+	return q->max_phys_segments;
+}
+
+static inline unsigned int queue_max_segment_size(struct request_queue *q)
+{
+	return q->max_segment_size;
+}
+
 static inline unsigned short queue_logical_block_size(struct request_queue *q)
 {
 	int retval = 512;
diff --git a/mm/bounce.c b/mm/bounce.c
index e590272fe7a..8dcd4315e01 100644
--- a/mm/bounce.c
+++ b/mm/bounce.c
@@ -192,7 +192,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
 		/*
 		 * is destination page below bounce pfn?
 		 */
-		if (page_to_pfn(page) <= q->bounce_pfn)
+		if (page_to_pfn(page) <= queue_bounce_pfn(q))
 			continue;
 
 		/*
@@ -284,7 +284,7 @@ void blk_queue_bounce(struct request_queue *q, struct bio **bio_orig)
 	 * don't waste time iterating over bio segments
 	 */
 	if (!(q->bounce_gfp & GFP_DMA)) {
-		if (q->bounce_pfn >= blk_max_pfn)
+		if (queue_bounce_pfn(q) >= blk_max_pfn)
 			return;
 		pool = page_pool;
 	} else {
-- 
cgit v1.2.3-70-g09d2


From 13685a1654b65357fb34066a98ef40445f7820fc Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Date: Wed, 10 Jun 2009 04:38:40 +0000
Subject: block: Add bio_list_peek()

Introduce bio_list_peek(), to obtain a pointer to the first bio on the bio_list
without actually removing it from the list. This is needed when you want to
serialize based on the list being empty or not.

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
 include/linux/bio.h | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'include/linux/bio.h')

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 12737be5860..2a04eb54c0d 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -590,6 +590,11 @@ static inline void bio_list_merge_head(struct bio_list *bl,
 	bl->head = bl2->head;
 }
 
+static inline struct bio *bio_list_peek(struct bio_list *bl)
+{
+	return bl->head;
+}
+
 static inline struct bio *bio_list_pop(struct bio_list *bl)
 {
 	struct bio *bio = bl->head;
-- 
cgit v1.2.3-70-g09d2