Merge tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux…

…/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Some request-based DM core and DM multipath fixes and cleanups

 - Constify a few variables in DM core and DM integrity

 - Add bufio optimization and checksum failure accounting to DM
   integrity

 - Fix DM integrity to avoid checking integrity of failed reads

 - Fix DM integrity to use init_completion

 - A couple DM log-writes target fixes

 - Simplify DAX flushing by eliminating the unnecessary flush
   abstraction that was stood up for DM's use.

* tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dax: remove the pmem_dax_ops->flush abstraction
  dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK
  dm integrity: make blk_integrity_profile structure const
  dm integrity: do not check integrity for failed read operations
  dm log writes: fix >512b sectorsize support
  dm log writes: don't use all the cpu while waiting to log blocks
  dm ioctl: constify ioctl lookup table
  dm: constify argument arrays
  dm integrity: count and display checksum failures
  dm integrity: optimize writing dm-bufio buffers that are partially changed
  dm rq: do not update rq partially in each ending bio
  dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior
  dm mpath: complain about unsupported __multipath_map_bio() return values
  dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through

drivers/dax/super.c

@@ -201,8 +201,10 @@ static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
 	if (!dax_dev)
 		return 0;
 
-	if (a == &dev_attr_write_cache.attr && !dax_dev->ops->flush)
+#ifndef CONFIG_ARCH_HAS_PMEM_API
+	if (a == &dev_attr_write_cache.attr)
 		return 0;
+#endif
 	return a->mode;
 }
 
@@ -267,18 +269,23 @@ size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
 }
 EXPORT_SYMBOL_GPL(dax_copy_from_iter);
 
-void dax_flush(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
-		size_t size)
+#ifdef CONFIG_ARCH_HAS_PMEM_API
+void arch_wb_cache_pmem(void *addr, size_t size);
+void dax_flush(struct dax_device *dax_dev, void *addr, size_t size)
 {
-	if (!dax_alive(dax_dev))
+	if (unlikely(!dax_alive(dax_dev)))
 		return;
 
-	if (!test_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags))
+	if (unlikely(!test_bit(DAXDEV_WRITE_CACHE, &dax_dev->flags)))
 		return;
 
-	if (dax_dev->ops->flush)
-		dax_dev->ops->flush(dax_dev, pgoff, addr, size);
+	arch_wb_cache_pmem(addr, size);
 }
+#else
+void dax_flush(struct dax_device *dax_dev, void *addr, size_t size)
+{
+}
+#endif
 EXPORT_SYMBOL_GPL(dax_flush);
 
 void dax_write_cache(struct dax_device *dax_dev, bool wc)

drivers/md/dm-bufio.c

@@ -63,6 +63,12 @@
 #define DM_BUFIO_BLOCK_SIZE_SLAB_LIMIT	(PAGE_SIZE >> 1)
 #define DM_BUFIO_BLOCK_SIZE_GFP_LIMIT	(PAGE_SIZE << (MAX_ORDER - 1))
 
+/*
+ * Align buffer writes to this boundary.
+ * Tests show that SSDs have the highest IOPS when using 4k writes.
+ */
+#define DM_BUFIO_WRITE_ALIGN		4096
+
 /*
  * dm_buffer->list_mode
  */
@@ -149,6 +155,10 @@ struct dm_buffer {
 	blk_status_t write_error;
 	unsigned long state;
 	unsigned long last_accessed;
+	unsigned dirty_start;
+	unsigned dirty_end;
+	unsigned write_start;
+	unsigned write_end;
 	struct dm_bufio_client *c;
 	struct list_head write_list;
 	struct bio bio;
@@ -560,7 +570,7 @@ static void dmio_complete(unsigned long error, void *context)
 }
 
 static void use_dmio(struct dm_buffer *b, int rw, sector_t sector,
-		     unsigned n_sectors, bio_end_io_t *end_io)
+		     unsigned n_sectors, unsigned offset, bio_end_io_t *end_io)
 {
 	int r;
 	struct dm_io_request io_req = {
@@ -578,10 +588,10 @@ static void use_dmio(struct dm_buffer *b, int rw, sector_t sector,
 
 	if (b->data_mode != DATA_MODE_VMALLOC) {
 		io_req.mem.type = DM_IO_KMEM;
-		io_req.mem.ptr.addr = b->data;
+		io_req.mem.ptr.addr = (char *)b->data + offset;
 	} else {
 		io_req.mem.type = DM_IO_VMA;
-		io_req.mem.ptr.vma = b->data;
+		io_req.mem.ptr.vma = (char *)b->data + offset;
 	}
 
 	b->bio.bi_end_io = end_io;
@@ -609,10 +619,10 @@ static void inline_endio(struct bio *bio)
 }
 
 static void use_inline_bio(struct dm_buffer *b, int rw, sector_t sector,
-			   unsigned n_sectors, bio_end_io_t *end_io)
+			   unsigned n_sectors, unsigned offset, bio_end_io_t *end_io)
 {
 	char *ptr;
-	int len;
+	unsigned len;
 
 	bio_init(&b->bio, b->bio_vec, DM_BUFIO_INLINE_VECS);
 	b->bio.bi_iter.bi_sector = sector;
@@ -625,29 +635,20 @@ static void use_inline_bio(struct dm_buffer *b, int rw, sector_t sector,
 	b->bio.bi_private = end_io;
 	bio_set_op_attrs(&b->bio, rw, 0);
 
-	/*
-	 * We assume that if len >= PAGE_SIZE ptr is page-aligned.
-	 * If len < PAGE_SIZE the buffer doesn't cross page boundary.
-	 */
-	ptr = b->data;
+	ptr = (char *)b->data + offset;
 	len = n_sectors << SECTOR_SHIFT;
 
-	if (len >= PAGE_SIZE)
-		BUG_ON((unsigned long)ptr & (PAGE_SIZE - 1));
-	else
-		BUG_ON((unsigned long)ptr & (len - 1));
-
 	do {
-		if (!bio_add_page(&b->bio, virt_to_page(ptr),
-				  len < PAGE_SIZE ? len : PAGE_SIZE,
+		unsigned this_step = min((unsigned)(PAGE_SIZE - offset_in_page(ptr)), len);
+		if (!bio_add_page(&b->bio, virt_to_page(ptr), this_step,
 				  offset_in_page(ptr))) {
 			BUG_ON(b->c->block_size <= PAGE_SIZE);
-			use_dmio(b, rw, sector, n_sectors, end_io);
+			use_dmio(b, rw, sector, n_sectors, offset, end_io);
 			return;
 		}
 
-		len -= PAGE_SIZE;
-		ptr += PAGE_SIZE;
+		len -= this_step;
+		ptr += this_step;
 	} while (len > 0);
 
 	submit_bio(&b->bio);
@@ -657,18 +658,33 @@ static void submit_io(struct dm_buffer *b, int rw, bio_end_io_t *end_io)
 {
 	unsigned n_sectors;
 	sector_t sector;
-
-	if (rw == WRITE && b->c->write_callback)
-		b->c->write_callback(b);
+	unsigned offset, end;
 
 	sector = (b->block << b->c->sectors_per_block_bits) + b->c->start;
-	n_sectors = 1 << b->c->sectors_per_block_bits;
+
+	if (rw != WRITE) {
+		n_sectors = 1 << b->c->sectors_per_block_bits;
+		offset = 0;
+	} else {
+		if (b->c->write_callback)
+			b->c->write_callback(b);
+		offset = b->write_start;
+		end = b->write_end;
+		offset &= -DM_BUFIO_WRITE_ALIGN;
+		end += DM_BUFIO_WRITE_ALIGN - 1;
+		end &= -DM_BUFIO_WRITE_ALIGN;
+		if (unlikely(end > b->c->block_size))
+			end = b->c->block_size;
+
+		sector += offset >> SECTOR_SHIFT;
+		n_sectors = (end - offset) >> SECTOR_SHIFT;
+	}
 
 	if (n_sectors <= ((DM_BUFIO_INLINE_VECS * PAGE_SIZE) >> SECTOR_SHIFT) &&
 	    b->data_mode != DATA_MODE_VMALLOC)
-		use_inline_bio(b, rw, sector, n_sectors, end_io);
+		use_inline_bio(b, rw, sector, n_sectors, offset, end_io);
 	else
-		use_dmio(b, rw, sector, n_sectors, end_io);
+		use_dmio(b, rw, sector, n_sectors, offset, end_io);
 }
 
 /*----------------------------------------------------------------
@@ -720,6 +736,9 @@ static void __write_dirty_buffer(struct dm_buffer *b,
 	clear_bit(B_DIRTY, &b->state);
 	wait_on_bit_lock_io(&b->state, B_WRITING, TASK_UNINTERRUPTIBLE);
 
+	b->write_start = b->dirty_start;
+	b->write_end = b->dirty_end;
+
 	if (!write_list)
 		submit_io(b, WRITE, write_endio);
 	else
@@ -1221,19 +1240,37 @@ void dm_bufio_release(struct dm_buffer *b)
 }
 EXPORT_SYMBOL_GPL(dm_bufio_release);
 
-void dm_bufio_mark_buffer_dirty(struct dm_buffer *b)
+void dm_bufio_mark_partial_buffer_dirty(struct dm_buffer *b,
+					unsigned start, unsigned end)
 {
 	struct dm_bufio_client *c = b->c;
 
+	BUG_ON(start >= end);
+	BUG_ON(end > b->c->block_size);
+
 	dm_bufio_lock(c);
 
 	BUG_ON(test_bit(B_READING, &b->state));
 
-	if (!test_and_set_bit(B_DIRTY, &b->state))
+	if (!test_and_set_bit(B_DIRTY, &b->state)) {
+		b->dirty_start = start;
+		b->dirty_end = end;
 		__relink_lru(b, LIST_DIRTY);
+	} else {
+		if (start < b->dirty_start)
+			b->dirty_start = start;
+		if (end > b->dirty_end)
+			b->dirty_end = end;
+	}
 
 	dm_bufio_unlock(c);
 }
+EXPORT_SYMBOL_GPL(dm_bufio_mark_partial_buffer_dirty);
+
+void dm_bufio_mark_buffer_dirty(struct dm_buffer *b)
+{
+	dm_bufio_mark_partial_buffer_dirty(b, 0, b->c->block_size);
+}
 EXPORT_SYMBOL_GPL(dm_bufio_mark_buffer_dirty);
 
 void dm_bufio_write_dirty_buffers_async(struct dm_bufio_client *c)
@@ -1398,6 +1435,8 @@ void dm_bufio_release_move(struct dm_buffer *b, sector_t new_block)
 		wait_on_bit_io(&b->state, B_WRITING,
 			       TASK_UNINTERRUPTIBLE);
 		set_bit(B_DIRTY, &b->state);
+		b->dirty_start = 0;
+		b->dirty_end = c->block_size;
 		__unlink_buffer(b);
 		__link_buffer(b, new_block, LIST_DIRTY);
 	} else {

drivers/md/dm-bufio.h

@@ -93,6 +93,15 @@ void dm_bufio_release(struct dm_buffer *b);
  */
 void dm_bufio_mark_buffer_dirty(struct dm_buffer *b);
 
+/*
+ * Mark a part of the buffer dirty.
+ *
+ * The specified part of the buffer is scheduled to be written. dm-bufio may
+ * write the specified part of the buffer or it may write a larger superset.
+ */
+void dm_bufio_mark_partial_buffer_dirty(struct dm_buffer *b,
+					unsigned start, unsigned end);
+
 /*
  * Initiate writing of dirty buffers, without waiting for completion.
  */

drivers/md/dm-cache-target.c

@@ -2306,7 +2306,7 @@ static void init_features(struct cache_features *cf)
 static int parse_features(struct cache_args *ca, struct dm_arg_set *as,
 			  char **error)
 {
-	static struct dm_arg _args[] = {
+	static const struct dm_arg _args[] = {
 		{0, 2, "Invalid number of cache feature arguments"},
 	};
 
@@ -2348,7 +2348,7 @@ static int parse_features(struct cache_args *ca, struct dm_arg_set *as,
 static int parse_policy(struct cache_args *ca, struct dm_arg_set *as,
 			char **error)
 {
-	static struct dm_arg _args[] = {
+	static const struct dm_arg _args[] = {
 		{0, 1024, "Invalid number of policy arguments"},
 	};
 

drivers/md/dm-crypt.c

@@ -2529,7 +2529,7 @@ static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **ar
 {
 	struct crypt_config *cc = ti->private;
 	struct dm_arg_set as;
-	static struct dm_arg _args[] = {
+	static const struct dm_arg _args[] = {
 		{0, 6, "Invalid number of feature args"},
 	};
 	unsigned int opt_params, val;

drivers/md/dm-flakey.c

@@ -51,7 +51,7 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
 	unsigned argc;
 	const char *arg_name;
 
-	static struct dm_arg _args[] = {
+	static const struct dm_arg _args[] = {
 		{0, 6, "Invalid number of feature args"},
 		{1, UINT_MAX, "Invalid corrupt bio byte"},
 		{0, 255, "Invalid corrupt value to write into bio byte (0-255)"},
@@ -178,7 +178,7 @@ static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
  */
 static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 {
-	static struct dm_arg _args[] = {
+	static const struct dm_arg _args[] = {
 		{0, UINT_MAX, "Invalid up interval"},
 		{0, UINT_MAX, "Invalid down interval"},
 	};