Merge branch 'linus' into perfcounters/core-v2

Merge reason: we have gathered quite a few conflicts, need to merge upstream

Conflicts:
	arch/powerpc/kernel/Makefile
	arch/x86/ia32/ia32entry.S
	arch/x86/include/asm/hardirq.h
	arch/x86/include/asm/unistd_32.h
	arch/x86/include/asm/unistd_64.h
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/irq.c
	arch/x86/kernel/syscall_table_32.S
	arch/x86/mm/iomap_32.c
	include/linux/sched.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>

10 files changed, 31 insertions, 924 deletions

diff --git a/block/Kconfig b/block/Kconfig
index 0cbb3b88b59..e7d12782bcf 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -44,22 +44,6 @@ config LBD
 
 	  If unsure, say N.
 
-config BLK_DEV_IO_TRACE
-	bool "Support for tracing block io actions"
-	depends on SYSFS
-	select RELAY
-	select DEBUG_FS
-	select TRACEPOINTS
-	help
-	  Say Y here if you want to be able to trace the block layer actions
-	  on a given queue. Tracing allows you to see any traffic happening
-	  on a block device queue. For more information (and the userspace
-	  support tools needed), fetch the blktrace tools from:
-
-	  git://git.kernel.dk/blktrace.git
-
-	  If unsure, say N.
-
 config BLK_DEV_BSG
 	bool "Block layer SG support v4 (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
diff --git a/block/Makefile b/block/Makefile
index bfe73049f93..e9fa4dd690f 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -13,6 +13,5 @@ obj-$(CONFIG_IOSCHED_AS)	+= as-iosched.o
 obj-$(CONFIG_IOSCHED_DEADLINE)	+= deadline-iosched.o
 obj-$(CONFIG_IOSCHED_CFQ)	+= cfq-iosched.o
 
-obj-$(CONFIG_BLK_DEV_IO_TRACE)	+= blktrace.o
 obj-$(CONFIG_BLOCK_COMPAT)	+= compat_ioctl.o
 obj-$(CONFIG_BLK_DEV_INTEGRITY)	+= blk-integrity.o
diff --git a/block/blk-core.c b/block/blk-core.c
index 29bcfac6c68..996ed906d8c 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -603,13 +603,10 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id)
 	q->queue_flags		= QUEUE_FLAG_DEFAULT;
 	q->queue_lock		= lock;
 
-	blk_queue_segment_boundary(q, BLK_SEG_BOUNDARY_MASK);
-
+	/*
+	 * This also sets hw/phys segments, boundary and size
+	 */
 	blk_queue_make_request(q, __make_request);
-	blk_queue_max_segment_size(q, MAX_SEGMENT_SIZE);
-
-	blk_queue_max_hw_segments(q, MAX_HW_SEGMENTS);
-	blk_queue_max_phys_segments(q, MAX_PHYS_SEGMENTS);
 
 	q->sg_reserved_size = INT_MAX;
 
@@ -735,7 +732,6 @@ static void freed_request(struct request_queue *q, int rw, int priv)
 		__freed_request(q, rw ^ 1);
 }
 
-#define blkdev_free_rq(list) list_entry((list)->next, struct request, queuelist)
 /*
  * Get a free request, queue_lock must be held.
  * Returns NULL on failure, with queue_lock held.
@@ -1066,6 +1062,9 @@ void __blk_put_request(struct request_queue *q, struct request *req)
 
 	elv_completed_request(q, req);
 
+	/* this is a bio leak */
+	WARN_ON(req->bio != NULL);
+
 	/*
 	 * Request may not have originated from ll_rw_blk. if not,
 	 * it didn't come out of our reserved rq pools
diff --git a/block/blk-merge.c b/block/blk-merge.c
index a104593e70c..e39cb24b767 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -39,14 +39,13 @@ void blk_recalc_rq_sectors(struct request *rq, int nsect)
 }
 
 static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
-					     struct bio *bio,
-					     unsigned int *seg_size_ptr)
+					     struct bio *bio)
 {
 	unsigned int phys_size;
 	struct bio_vec *bv, *bvprv = NULL;
 	int cluster, i, high, highprv = 1;
 	unsigned int seg_size, nr_phys_segs;
-	struct bio *fbio;
+	struct bio *fbio, *bbio;
 
 	if (!bio)
 		return 0;
@@ -87,26 +86,20 @@ new_segment:
 			seg_size = bv->bv_len;
 			highprv = high;
 		}
+		bbio = bio;
 	}
 
-	if (seg_size_ptr)
-		*seg_size_ptr = seg_size;
+	if (nr_phys_segs == 1 && seg_size > fbio->bi_seg_front_size)
+		fbio->bi_seg_front_size = seg_size;
+	if (seg_size > bbio->bi_seg_back_size)
+		bbio->bi_seg_back_size = seg_size;
 
 	return nr_phys_segs;
 }
 
 void blk_recalc_rq_segments(struct request *rq)
 {
-	unsigned int seg_size = 0, phys_segs;
-
-	phys_segs = __blk_recalc_rq_segments(rq->q, rq->bio, &seg_size);
-
-	if (phys_segs == 1 && seg_size > rq->bio->bi_seg_front_size)
-		rq->bio->bi_seg_front_size = seg_size;
-	if (seg_size > rq->biotail->bi_seg_back_size)
-		rq->biotail->bi_seg_back_size = seg_size;
-
-	rq->nr_phys_segments = phys_segs;
+	rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio);
 }
 
 void blk_recount_segments(struct request_queue *q, struct bio *bio)
@@ -114,7 +107,7 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio)
 	struct bio *nxt = bio->bi_next;
 
 	bio->bi_next = NULL;
-	bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio, NULL);
+	bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio);
 	bio->bi_next = nxt;
 	bio->bi_flags |= (1 << BIO_SEG_VALID);
 }
@@ -410,6 +403,8 @@ static int attempt_merge(struct request_queue *q, struct request *req,
 	if (blk_rq_cpu_valid(next))
 		req->cpu = next->cpu;
 
+	/* owner-ship of bio passed from next to req */
+	next->bio = NULL;
 	__blk_put_request(q, next);
 	return 1;
 }
diff --git a/block/blk-softirq.c b/block/blk-softirq.c
index ce0efc6b26d..ee9c2160222 100644
--- a/block/blk-softirq.c
+++ b/block/blk-softirq.c
@@ -64,7 +64,7 @@ static int raise_blk_irq(int cpu, struct request *rq)
 		data->info = rq;
 		data->flags = 0;
 
-		__smp_call_function_single(cpu, data);
+		__smp_call_function_single(cpu, data, 0);
 		return 0;
 	}
 
diff --git a/block/blk.h b/block/blk.h
index 0dce92c3749..3ee94358b43 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -102,7 +102,7 @@ static inline int blk_cpu_to_group(int cpu)
 	const struct cpumask *mask = cpu_coregroup_mask(cpu);
 	return cpumask_first(mask);
 #elif defined(CONFIG_SCHED_SMT)
-	return first_cpu(per_cpu(cpu_sibling_map, cpu));
+	return cpumask_first(topology_thread_cpumask(cpu));
 #else
 	return cpu;
 #endif
diff --git a/block/blktrace.c b/block/blktrace.c
deleted file mode 100644
index 7cf9d1ff45a..00000000000
--- a/block/blktrace.c
+++ /dev/null
@@ -1,860 +0,0 @@
-/*
- * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- */
-#include <linux/kernel.h>
-#include <linux/blkdev.h>
-#include <linux/blktrace_api.h>
-#include <linux/percpu.h>
-#include <linux/init.h>
-#include <linux/mutex.h>
-#include <linux/debugfs.h>
-#include <linux/time.h>
-#include <trace/block.h>
-#include <asm/uaccess.h>
-
-static unsigned int blktrace_seq __read_mostly = 1;
-
-/* Global reference count of probes */
-static DEFINE_MUTEX(blk_probe_mutex);
-static atomic_t blk_probes_ref = ATOMIC_INIT(0);
-
-static int blk_register_tracepoints(void);
-static void blk_unregister_tracepoints(void);
-
-/*
- * Send out a notify message.
- */
-static void trace_note(struct blk_trace *bt, pid_t pid, int action,
-		       const void *data, size_t len)
-{
-	struct blk_io_trace *t;
-
-	t = relay_reserve(bt->rchan, sizeof(*t) + len);
-	if (t) {
-		const int cpu = smp_processor_id();
-
-		t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
-		t->time = ktime_to_ns(ktime_get());
-		t->device = bt->dev;
-		t->action = action;
-		t->pid = pid;
-		t->cpu = cpu;
-		t->pdu_len = len;
-		memcpy((void *) t + sizeof(*t), data, len);
-	}
-}
-
-/*
- * Send out a notify for this process, if we haven't done so since a trace
- * started
- */
-static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk)
-{
-	tsk->btrace_seq = blktrace_seq;
-	trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm));
-}
-
-static void trace_note_time(struct blk_trace *bt)
-{
-	struct timespec now;
-	unsigned long flags;
-	u32 words[2];
-
-	getnstimeofday(&now);
-	words[0] = now.tv_sec;
-	words[1] = now.tv_nsec;
-
-	local_irq_save(flags);
-	trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words));
-	local_irq_restore(flags);
-}
-
-void __trace_note_message(struct blk_trace *bt, const char *fmt, ...)
-{
-	int n;
-	va_list args;
-	unsigned long flags;
-	char *buf;
-
-	local_irq_save(flags);
-	buf = per_cpu_ptr(bt->msg_data, smp_processor_id());
-	va_start(args, fmt);
-	n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args);
-	va_end(args);
-
-	trace_note(bt, 0, BLK_TN_MESSAGE, buf, n);
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL_GPL(__trace_note_message);
-
-static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector,
-			 pid_t pid)
-{
-	if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0)
-		return 1;
-	if (sector < bt->start_lba || sector > bt->end_lba)
-		return 1;
-	if (bt->pid && pid != bt->pid)
-		return 1;
-
-	return 0;
-}
-
-/*
- * Data direction bit lookup
- */
-static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) };
-
-/* The ilog2() calls fall out because they're constant */
-#define MASK_TC_BIT(rw, __name) ( (rw & (1 << BIO_RW_ ## __name)) << \
-	  (ilog2(BLK_TC_ ## __name) + BLK_TC_SHIFT - BIO_RW_ ## __name) )
-
-/*
- * The worker for the various blk_add_trace*() types. Fills out a
- * blk_io_trace structure and places it in a per-cpu subbuffer.
- */
-static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
-		     int rw, u32 what, int error, int pdu_len, void *pdu_data)
-{
-	struct task_struct *tsk = current;
-	struct blk_io_trace *t;
-	unsigned long flags;
-	unsigned long *sequence;
-	pid_t pid;
-	int cpu;
-
-	if (unlikely(bt->trace_state != Blktrace_running))
-		return;
-
-	what |= ddir_act[rw & WRITE];
-	what |= MASK_TC_BIT(rw, BARRIER);
-	what |= MASK_TC_BIT(rw, SYNCIO);
-	what |= MASK_TC_BIT(rw, AHEAD);
-	what |= MASK_TC_BIT(rw, META);
-	what |= MASK_TC_BIT(rw, DISCARD);
-
-	pid = tsk->pid;
-	if (unlikely(act_log_check(bt, what, sector, pid)))
-		return;
-
-	/*
-	 * A word about the locking here - we disable interrupts to reserve
-	 * some space in the relay per-cpu buffer, to prevent an irq
-	 * from coming in and stepping on our toes.
-	 */
-	local_irq_save(flags);
-
-	if (unlikely(tsk->btrace_seq != blktrace_seq))
-		trace_note_tsk(bt, tsk);
-
-	t = relay_reserve(bt->rchan, sizeof(*t) + pdu_len);
-	if (t) {
-		cpu = smp_processor_id();
-		sequence = per_cpu_ptr(bt->sequence, cpu);
-
-		t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
-		t->sequence = ++(*sequence);
-		t->time = ktime_to_ns(ktime_get());
-		t->sector = sector;
-		t->bytes = bytes;
-		t->action = what;
-		t->pid = pid;
-		t->device = bt->dev;
-		t->cpu = cpu;
-		t->error = error;
-		t->pdu_len = pdu_len;
-
-		if (pdu_len)
-			memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
-	}
-
-	local_irq_restore(flags);
-}
-
-static struct dentry *blk_tree_root;
-static DEFINE_MUTEX(blk_tree_mutex);
-
-static void blk_trace_cleanup(struct blk_trace *bt)
-{
-	debugfs_remove(bt->msg_file);
-	debugfs_remove(bt->dropped_file);
-	relay_close(bt->rchan);
-	free_percpu(bt->sequence);
-	free_percpu(bt->msg_data);
-	kfree(bt);
-	mutex_lock(&blk_probe_mutex);
-	if (atomic_dec_and_test(&blk_probes_ref))
-		blk_unregister_tracepoints();
-	mutex_unlock(&blk_probe_mutex);
-}
-
-int blk_trace_remove(struct request_queue *q)
-{
-	struct blk_trace *bt;
-
-	bt = xchg(&q->blk_trace, NULL);
-	if (!bt)
-		return -EINVAL;
-
-	if (bt->trace_state == Blktrace_setup ||
-	    bt->trace_state == Blktrace_stopped)
-		blk_trace_cleanup(bt);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(blk_trace_remove);
-
-static int blk_dropped_open(struct inode *inode, struct file *filp)
-{
-	filp->private_data = inode->i_private;
-
-	return 0;
-}
-
-static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	struct blk_trace *bt = filp->private_data;
-	char buf[16];
-
-	snprintf(buf, sizeof(buf), "%u\n", atomic_read(&bt->dropped));
-
-	return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf));
-}
-
-static const struct file_operations blk_dropped_fops = {
-	.owner =	THIS_MODULE,
-	.open =		blk_dropped_open,
-	.read =		blk_dropped_read,
-};
-
-static int blk_msg_open(struct inode *inode, struct file *filp)
-{
-	filp->private_data = inode->i_private;
-
-	return 0;
-}
-
-static ssize_t blk_msg_write(struct file *filp, const char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	char *msg;
-	struct blk_trace *bt;
-
-	if (count > BLK_TN_MAX_MSG)
-		return -EINVAL;
-
-	msg = kmalloc(count, GFP_KERNEL);
-	if (msg == NULL)
-		return -ENOMEM;
-
-	if (copy_from_user(msg, buffer, count)) {
-		kfree(msg);
-		return -EFAULT;
-	}
-
-	bt = filp->private_data;
-	__trace_note_message(bt, "%s", msg);
-	kfree(msg);
-
-	return count;
-}
-
-static const struct file_operations blk_msg_fops = {
-	.owner =	THIS_MODULE,
-	.open =		blk_msg_open,
-	.write =	blk_msg_write,
-};
-
-/*
- * Keep track of how many times we encountered a full subbuffer, to aid
- * the user space app in telling how many lost events there were.
- */
-static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
-				     void *prev_subbuf, size_t prev_padding)
-{
-	struct blk_trace *bt;
-
-	if (!relay_buf_full(buf))
-		return 1;
-
-	bt = buf->chan->private_data;
-	atomic_inc(&bt->dropped);
-	return 0;
-}
-
-static int blk_remove_buf_file_callback(struct dentry *dentry)
-{
-	struct dentry *parent = dentry->d_parent;
-	debugfs_remove(dentry);
-
-	/*
-	* this will fail for all but the last file, but that is ok. what we
-	* care about is the top level buts->name directory going away, when
-	* the last trace file is gone. Then we don't have to rmdir() that
-	* manually on trace stop, so it nicely solves the issue with
-	* force killing of running traces.
-	*/
-
-	debugfs_remove(parent);
-	return 0;
-}
-
-static struct dentry *blk_create_buf_file_callback(const char *filename,
-						   struct dentry *parent,
-						   int mode,
-						   struct rchan_buf *buf,
-						   int *is_global)
-{
-	return debugfs_create_file(filename, mode, parent, buf,
-					&relay_file_operations);
-}
-
-static struct rchan_callbacks blk_relay_callbacks = {
-	.subbuf_start		= blk_subbuf_start_callback,
-	.create_buf_file	= blk_create_buf_file_callback,
-	.remove_buf_file	= blk_remove_buf_file_callback,
-};
-
-/*
- * Setup everything required to start tracing
- */
-int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
-			struct blk_user_trace_setup *buts)
-{
-	struct blk_trace *old_bt, *bt = NULL;
-	struct dentry *dir = NULL;
-	int ret, i;
-
-	if (!buts->buf_size || !buts->buf_nr)
-		return -EINVAL;
-
-	strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
-	buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0';
-
-	/*
-	 * some device names have larger paths - convert the slashes
-	 * to underscores for this to work as expected
-	 */
-	for (i = 0; i < strlen(buts->name); i++)
-		if (buts->name[i] == '/')
-			buts->name[i] = '_';
-
-	ret = -ENOMEM;
-	bt = kzalloc(sizeof(*bt), GFP_KERNEL);
-	if (!bt)
-		goto err;
-
-	bt->sequence = alloc_percpu(unsigned long);
-	if (!bt->sequence)
-		goto err;
-
-	bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG);
-	if (!bt->msg_data)
-		goto err;
-
-	ret = -ENOENT;
-
-	if (!blk_tree_root) {
-		blk_tree_root = debugfs_create_dir("block", NULL);
-		if (!blk_tree_root)
-			return -ENOMEM;
-	}
-
-	dir = debugfs_create_dir(buts->name, blk_tree_root);
-
-	if (!dir)
-		goto err;
-
-	bt->dir = dir;
-	bt->dev = dev;
-	atomic_set(&bt->dropped, 0);
-
-	ret = -EIO;
-	bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops);
-	if (!bt->dropped_file)
-		goto err;
-
-	bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops);
-	if (!bt->msg_file)
-		goto err;
-
-	bt->rchan = relay_open("trace", dir, buts->buf_size,
-				buts->buf_nr, &blk_relay_callbacks, bt);
-	if (!bt->rchan)
-		goto err;
-
-	bt->act_mask = buts->act_mask;
-	if (!bt->act_mask)
-		bt->act_mask = (u16) -1;
-
-	bt->start_lba = buts->start_lba;
-	bt->end_lba = buts->end_lba;
-	if (!bt->end_lba)
-		bt->end_lba = -1ULL;
-
-	bt->pid = buts->pid;
-	bt->trace_state = Blktrace_setup;
-
-	mutex_lock(&blk_probe_mutex);
-	if (atomic_add_return(1, &blk_probes_ref) == 1) {
-		ret = blk_register_tracepoints();
-		if (ret)
-			goto probe_err;
-	}
-	mutex_unlock(&blk_probe_mutex);
-
-	ret = -EBUSY;
-	old_bt = xchg(&q->blk_trace, bt);
-	if (old_bt) {
-		(void) xchg(&q->blk_trace, old_bt);
-		goto err;
-	}
-
-	return 0;
-probe_err:
-	atomic_dec(&blk_probes_ref);
-	mutex_unlock(&blk_probe_mutex);
-err:
-	if (bt) {
-		if (bt->msg_file)
-			debugfs_remove(bt->msg_file);
-		if (bt->dropped_file)
-			debugfs_remove(bt->dropped_file);
-		free_percpu(bt->sequence);
-		free_percpu(bt->msg_data);
-		if (bt->rchan)
-			relay_close(bt->rchan);
-		kfree(bt);
-	}
-	return ret;
-}
-
-int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
-		    char __user *arg)
-{
-	struct blk_user_trace_setup buts;
-	int ret;
-
-	ret = copy_from_user(&buts, arg, sizeof(buts));
-	if (ret)
-		return -EFAULT;
-
-	ret = do_blk_trace_setup(q, name, dev, &buts);
-	if (ret)
-		return ret;
-
-	if (copy_to_user(arg, &buts, sizeof(buts)))
-		return -EFAULT;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(blk_trace_setup);
-
-int blk_trace_startstop(struct request_queue *q, int start)
-{
-	struct blk_trace *bt;
-	int ret;
-
-	if ((bt = q->blk_trace) == NULL)
-		return -EINVAL;
-
-	/*
-	 * For starting a trace, we can transition from a setup or stopped
-	 * trace. For stopping a trace, the state must be running
-	 */
-	ret = -EINVAL;
-	if (start) {
-		if (bt->trace_state == Blktrace_setup ||
-		    bt->trace_state == Blktrace_stopped) {
-			blktrace_seq++;
-			smp_mb();
-			bt->trace_state = Blktrace_running;
-
-			trace_note_time(bt);
-			ret = 0;
-		}
-	} else {
-		if (bt->trace_state == Blktrace_running) {
-			bt->trace_state = Blktrace_stopped;
-			relay_flush(bt->rchan);
-			ret = 0;
-		}
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(blk_trace_startstop);
-
-/**
- * blk_trace_ioctl: - handle the ioctls associated with tracing
- * @bdev:	the block device
- * @cmd: 	the ioctl cmd
- * @arg:	the argument data, if any
- *
- **/
-int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
-{
-	struct request_queue *q;
-	int ret, start = 0;
-	char b[BDEVNAME_SIZE];
-
-	q = bdev_get_queue(bdev);
-	if (!q)
-		return -ENXIO;
-
-	mutex_lock(&bdev->bd_mutex);
-
-	switch (cmd) {
-	case BLKTRACESETUP:
-		bdevname(bdev, b);
-		ret = blk_trace_setup(q, b, bdev->bd_dev, arg);
-		break;
-	case BLKTRACESTART:
-		start = 1;
-	case BLKTRACESTOP:
-		ret = blk_trace_startstop(q, start);
-		break;
-	case BLKTRACETEARDOWN:
-		ret = blk_trace_remove(q);
-		break;
-	default:
-		ret = -ENOTTY;
-		break;
-	}
-
-	mutex_unlock(&bdev->bd_mutex);
-	return ret;
-}
-
-/**
- * blk_trace_shutdown: - stop and cleanup trace structures
- * @q:    the request queue associated with the device
- *
- **/
-void blk_trace_shutdown(struct request_queue *q)
-{
-	if (q->blk_trace) {
-		blk_trace_startstop(q, 0);
-		blk_trace_remove(q);
-	}
-}
-
-/*
- * blktrace probes
- */
-
-/**
- * blk_add_trace_rq - Add a trace for a request oriented action
- * @q:		queue the io is for
- * @rq:		the source request
- * @what:	the action
- *
- * Description:
- *     Records an action against a request. Will log the bio offset + size.
- *
- **/
-static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
-				    u32 what)
-{
-	struct blk_trace *bt = q->blk_trace;
-	int rw = rq->cmd_flags & 0x03;
-
-	if (likely(!bt))
-		return;
-
-	if (blk_discard_rq(rq))
-		rw |= (1 << BIO_RW_DISCARD);
-
-	if (blk_pc_request(rq)) {
-		what |= BLK_TC_ACT(BLK_TC_PC);
-		__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors,
-				sizeof(rq->cmd), rq->cmd);
-	} else  {
-		what |= BLK_TC_ACT(BLK_TC_FS);
-		__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9,
-				rw, what, rq->errors, 0, NULL);
-	}
-}
-
-static void blk_add_trace_rq_abort(struct request_queue *q, struct request *rq)
-{
-	blk_add_trace_rq(q, rq, BLK_TA_ABORT);
-}
-
-static void blk_add_trace_rq_insert(struct request_queue *q, struct request *rq)
-{
-	blk_add_trace_rq(q, rq, BLK_TA_INSERT);
-}
-
-static void blk_add_trace_rq_issue(struct request_queue *q, struct request *rq)
-{
-	blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
-}
-
-static void blk_add_trace_rq_requeue(struct request_queue *q, struct request *rq)
-{
-	blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
-}
-
-static void blk_add_trace_rq_complete(struct request_queue *q, struct request *rq)
-{
-	blk_add_trace_rq(q, rq, BLK_TA_COMPLETE);
-}
-
-/**
- * blk_add_trace_bio - Add a trace for a bio oriented action
- * @q:		queue the io is for
- * @bio:	the source bio
- * @what:	the action
- *
- * Description:
- *     Records an action against a bio. Will log the bio offset + size.
- *
- **/
-static void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
-				     u32 what)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (likely(!bt))
-		return;
-
-	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what,
-			!bio_flagged(bio, BIO_UPTODATE), 0, NULL);
-}
-
-static void blk_add_trace_bio_bounce(struct request_queue *q, struct bio *bio)
-{
-	blk_add_trace_bio(q, bio, BLK_TA_BOUNCE);
-}
-
-static void blk_add_trace_bio_complete(struct request_queue *q, struct bio *bio)
-{
-	blk_add_trace_bio(q, bio, BLK_TA_COMPLETE);
-}
-
-static void blk_add_trace_bio_backmerge(struct request_queue *q, struct bio *bio)
-{
-	blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
-}
-
-static void blk_add_trace_bio_frontmerge(struct request_queue *q, struct bio *bio)
-{
-	blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
-}
-
-static void blk_add_trace_bio_queue(struct request_queue *q, struct bio *bio)
-{
-	blk_add_trace_bio(q, bio, BLK_TA_QUEUE);
-}
-
-static void blk_add_trace_getrq(struct request_queue *q, struct bio *bio, int rw)
-{
-	if (bio)
-		blk_add_trace_bio(q, bio, BLK_TA_GETRQ);
-	else {
-		struct blk_trace *bt = q->blk_trace;
-
-		if (bt)
-			__blk_add_trace(bt, 0, 0, rw, BLK_TA_GETRQ, 0, 0, NULL);
-	}
-}
-
-
-static void blk_add_trace_sleeprq(struct request_queue *q, struct bio *bio, int rw)
-{
-	if (bio)
-		blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ);
-	else {
-		struct blk_trace *bt = q->blk_trace;
-
-		if (bt)
-			__blk_add_trace(bt, 0, 0, rw, BLK_TA_SLEEPRQ, 0, 0, NULL);
-	}
-}
-
-static void blk_add_trace_plug(struct request_queue *q)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (bt)
-		__blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL);
-}
-
-static void blk_add_trace_unplug_io(struct request_queue *q)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (bt) {
-		unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE];
-		__be64 rpdu = cpu_to_be64(pdu);
-
-		__blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0,
-				sizeof(rpdu), &rpdu);
-	}
-}
-
-static void blk_add_trace_unplug_timer(struct request_queue *q)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (bt) {
-		unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE];
-		__be64 rpdu = cpu_to_be64(pdu);
-
-		__blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0,
-				sizeof(rpdu), &rpdu);
-	}
-}
-
-static void blk_add_trace_split(struct request_queue *q, struct bio *bio,
-				unsigned int pdu)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (bt) {
-		__be64 rpdu = cpu_to_be64(pdu);
-
-		__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw,
-				BLK_TA_SPLIT, !bio_flagged(bio, BIO_UPTODATE),
-				sizeof(rpdu), &rpdu);
-	}
-}
-
-/**
- * blk_add_trace_remap - Add a trace for a remap operation
- * @q:		queue the io is for
- * @bio:	the source bio
- * @dev:	target device
- * @from:	source sector
- * @to:		target sector
- *
- * Description:
- *     Device mapper or raid target sometimes need to split a bio because
- *     it spans a stripe (or similar). Add a trace for that action.
- *
- **/
-static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
-				       dev_t dev, sector_t from, sector_t to)
-{
-	struct blk_trace *bt = q->blk_trace;
-	struct blk_io_trace_remap r;
-
-	if (likely(!bt))
-		return;
-
-	r.device = cpu_to_be32(dev);
-	r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
-	r.sector = cpu_to_be64(to);
-
-	__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP,
-			!bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
-}
-
-/**
- * blk_add_driver_data - Add binary message with driver-specific data
- * @q:		queue the io is for
- * @rq:		io request
- * @data:	driver-specific data
- * @len:	length of driver-specific data
- *
- * Description:
- *     Some drivers might want to write driver-specific data per request.
- *
- **/
-void blk_add_driver_data(struct request_queue *q,
-			 struct request *rq,
-			 void *data, size_t len)
-{
-	struct blk_trace *bt = q->blk_trace;
-
-	if (likely(!bt))
-		return;
-
-	if (blk_pc_request(rq))
-		__blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA,
-				rq->errors, len, data);
-	else
-		__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9,
-				0, BLK_TA_DRV_DATA, rq->errors, len, data);
-}
-EXPORT_SYMBOL_GPL(blk_add_driver_data);
-
-static int blk_register_tracepoints(void)
-{
-	int ret;
-
-	ret = register_trace_block_rq_abort(blk_add_trace_rq_abort);
-	WARN_ON(ret);
-	ret = register_trace_block_rq_insert(blk_add_trace_rq_insert);
-	WARN_ON(ret);
-	ret = register_trace_block_rq_issue(blk_add_trace_rq_issue);
-	WARN_ON(ret);
-	ret = register_trace_block_rq_requeue(blk_add_trace_rq_requeue);
-	WARN_ON(ret);
-	ret = register_trace_block_rq_complete(blk_add_trace_rq_complete);
-	WARN_ON(ret);
-	ret = register_trace_block_bio_bounce(blk_add_trace_bio_bounce);
-	WARN_ON(ret);
-	ret = register_trace_block_bio_complete(blk_add_trace_bio_complete);
-	WARN_ON(ret);
-	ret = register_trace_block_bio_backmerge(blk_add_trace_bio_backmerge);
-	WARN_ON(ret);
-	ret = register_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge);
-	WARN_ON(ret);
-	ret = register_trace_block_bio_queue(blk_add_trace_bio_queue);
-	WARN_ON(ret);
-	ret = register_trace_block_getrq(blk_add_trace_getrq);
-	WARN_ON(ret);
-	ret = register_trace_block_sleeprq(blk_add_trace_sleeprq);
-	WARN_ON(ret);
-	ret = register_trace_block_plug(blk_add_trace_plug);
-	WARN_ON(ret);
-	ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer);
-	WARN_ON(ret);
-	ret = register_trace_block_unplug_io(blk_add_trace_unplug_io);
-	WARN_ON(ret);
-	ret = register_trace_block_split(blk_add_trace_split);
-	WARN_ON(ret);
-	ret = register_trace_block_remap(blk_add_trace_remap);
-	WARN_ON(ret);
-	return 0;
-}
-
-static void blk_unregister_tracepoints(void)
-{
-	unregister_trace_block_remap(blk_add_trace_remap);
-	unregister_trace_block_split(blk_add_trace_split);
-	unregister_trace_block_unplug_io(blk_add_trace_unplug_io);
-	unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer);
-	unregister_trace_block_plug(blk_add_trace_plug);
-	unregister_trace_block_sleeprq(blk_add_trace_sleeprq);
-	unregister_trace_block_getrq(blk_add_trace_getrq);
-	unregister_trace_block_bio_queue(blk_add_trace_bio_queue);
-	unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge);
-	unregister_trace_block_bio_backmerge(blk_add_trace_bio_backmerge);
-	unregister_trace_block_bio_complete(blk_add_trace_bio_complete);
-	unregister_trace_block_bio_bounce(blk_add_trace_bio_bounce);
-	unregister_trace_block_rq_complete(blk_add_trace_rq_complete);
-	unregister_trace_block_rq_requeue(blk_add_trace_rq_requeue);
-	unregister_trace_block_rq_issue(blk_add_trace_rq_issue);
-	unregister_trace_block_rq_insert(blk_add_trace_rq_insert);
-	unregister_trace_block_rq_abort(blk_add_trace_rq_abort);
-
-	tracepoint_synchronize_unregister();
-}
diff --git a/block/bsg.c b/block/bsg.c
index 0ce8806dd0c..206060e795d 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -218,9 +218,6 @@ bsg_validate_sgv4_hdr(struct request_queue *q, struct sg_io_v4 *hdr, int *rw)
 
 	if (hdr->guard != 'Q')
 		return -EINVAL;
-	if (hdr->dout_xfer_len > (q->max_sectors << 9) ||
-	    hdr->din_xfer_len > (q->max_sectors << 9))
-		return -EIO;
 
 	switch (hdr->protocol) {
 	case BSG_PROTOCOL_SCSI:
@@ -353,6 +350,8 @@ static void bsg_rq_end_io(struct request *rq, int uptodate)
 static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
 			    struct bsg_command *bc, struct request *rq)
 {
+	int at_head = (0 == (bc->hdr.flags & BSG_FLAG_Q_AT_TAIL));
+
 	/*
 	 * add bc command to busy queue and submit rq for io
 	 */
@@ -368,7 +367,7 @@ static void bsg_add_command(struct bsg_device *bd, struct request_queue *q,
 	dprintk("%s: queueing rq %p, bc %p\n", bd->name, rq, bc);
 
 	rq->end_io_data = bc;
-	blk_execute_rq_nowait(q, NULL, rq, 1, bsg_rq_end_io);
+	blk_execute_rq_nowait(q, NULL, rq, at_head, bsg_rq_end_io);
 }
 
 static struct bsg_command *bsg_next_done_cmd(struct bsg_device *bd)
@@ -924,6 +923,7 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		struct request *rq;
 		struct bio *bio, *bidi_bio = NULL;
 		struct sg_io_v4 hdr;
+		int at_head;
 		u8 sense[SCSI_SENSE_BUFFERSIZE];
 
 		if (copy_from_user(&hdr, uarg, sizeof(hdr)))
@@ -936,7 +936,9 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		bio = rq->bio;
 		if (rq->next_rq)
 			bidi_bio = rq->next_rq->bio;
-		blk_execute_rq(bd->queue, NULL, rq, 0);
+
+		at_head = (0 == (hdr.flags & BSG_FLAG_Q_AT_TAIL));
+		blk_execute_rq(bd->queue, NULL, rq, at_head);
 		ret = blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio);
 
 		if (copy_to_user(uarg, &hdr, sizeof(hdr)))
diff --git a/block/cmd-filter.c b/block/cmd-filter.c
index 504b275e1b9..572bbc2f900 100644
--- a/block/cmd-filter.c
+++ b/block/cmd-filter.c
@@ -22,6 +22,7 @@
 #include <linux/spinlock.h>
 #include <linux/capability.h>
 #include <linux/bitops.h>
+#include <linux/blkdev.h>
 
 #include <scsi/scsi.h>
 #include <linux/cdrom.h>
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index ee9c67d7e1b..626ee274c5c 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -214,21 +214,10 @@ static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
 	return 0;
 }
 
-/*
- * unmap a request that was previously mapped to this sg_io_hdr. handles
- * both sg and non-sg sg_io_hdr.
- */
-static int blk_unmap_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr)
-{
-	blk_rq_unmap_user(rq->bio);
-	blk_put_request(rq);
-	return 0;
-}
-
 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 				 struct bio *bio)
 {
-	int r, ret = 0;
+	int ret = 0;
 
 	/*
 	 * fill in all the output members
@@ -253,12 +242,10 @@ static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 			ret = -EFAULT;
 	}
 
-	rq->bio = bio;
-	r = blk_unmap_sghdr_rq(rq, hdr);
-	if (ret)
-		r = ret;
+	blk_rq_unmap_user(bio);
+	blk_put_request(rq);
 
-	return r;
+	return ret;
 }
 
 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,