diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index ac0b39d..eee994f 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -280,4 +280,11 @@ static inline void btrfs_inode_resume_unlocked_dio(struct inode *inode)
 		  &BTRFS_I(inode)->runtime_flags);
 }
 
+static inline u64 btrfs_align_size(struct inode *inode)
+{
+	if (BTRFS_I(inode)->root->sectorsize < PAGE_CACHE_SIZE)
+		return (u64)PAGE_CACHE_SIZE;
+	else
+		return (u64)BTRFS_I(inode)->root->sectorsize;
+}
 #endif
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 1499b27..259f2c5 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -89,9 +89,10 @@ static inline int compressed_bio_size(struct btrfs_root *root,
 				      unsigned long disk_size)
 {
 	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
+	int align_size = max_t(size_t, root->sectorsize, PAGE_CACHE_SIZE);
 
 	return sizeof(struct compressed_bio) +
-		((disk_size + root->sectorsize - 1) / root->sectorsize) *
+		((disk_size + align_size - 1) / align_size) *
 		csum_size;
 }
 
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 79cf87f..621af18 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3617,8 +3617,8 @@ int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
 	u64 used;
 	int ret = 0, committed = 0, alloc_chunk = 1;
 
-	/* make sure bytes are sectorsize aligned */
-	bytes = ALIGN(bytes, root->sectorsize);
+	/* make sure bytes are appropriately aligned */
+	bytes = ALIGN(bytes, btrfs_align_size(inode));
 
 	if (btrfs_is_free_space_inode(inode)) {
 		committed = 1;
@@ -3726,8 +3726,8 @@ void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes)
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_space_info *data_sinfo;
 
-	/* make sure bytes are sectorsize aligned */
-	bytes = ALIGN(bytes, root->sectorsize);
+	/* make sure bytes are appropriately aligned */
+	bytes = ALIGN(bytes, btrfs_align_size(inode));
 
 	data_sinfo = root->fs_info->data_sinfo;
 	spin_lock(&data_sinfo->lock);
@@ -4988,7 +4988,7 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 	if (delalloc_lock)
 		mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
 
-	num_bytes = ALIGN(num_bytes, root->sectorsize);
+	num_bytes = ALIGN(num_bytes, btrfs_align_size(inode));
 
 	spin_lock(&BTRFS_I(inode)->lock);
 	BTRFS_I(inode)->outstanding_extents++;
@@ -5126,7 +5126,7 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
 	u64 to_free = 0;
 	unsigned dropped;
 
-	num_bytes = ALIGN(num_bytes, root->sectorsize);
+	num_bytes = ALIGN(num_bytes, btrfs_align_size(inode));
 	spin_lock(&BTRFS_I(inode)->lock);
 	dropped = drop_outstanding_extent(inode);
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index a1a849b..e1992ed 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2766,7 +2766,7 @@ static int __do_readpage(struct extent_io_tree *tree,
 	size_t pg_offset = 0;
 	size_t iosize;
 	size_t disk_io_size;
-	size_t blocksize = inode->i_sb->s_blocksize;
+	size_t blocksize = btrfs_align_size(inode);
 	unsigned long this_bio_flag = *bio_flags & EXTENT_BIO_PARENT_LOCKED;
 
 	set_page_extent_mapped(page);
@@ -3078,7 +3078,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 	int ret;
 	int nr = 0;
 	size_t pg_offset = 0;
-	size_t blocksize;
 	loff_t i_size = i_size_read(inode);
 	unsigned long end_index = i_size >> PAGE_CACHE_SHIFT;
 	u64 nr_delalloc;
@@ -3218,8 +3217,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 		goto done;
 	}
 
-	blocksize = inode->i_sb->s_blocksize;
-
 	while (cur <= end) {
 		if (cur >= last_byte) {
 			if (tree->ops && tree->ops->writepage_end_io_hook)
@@ -3238,7 +3235,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 		BUG_ON(extent_map_end(em) <= cur);
 		BUG_ON(end < cur);
 		iosize = min(extent_map_end(em) - cur, end - cur + 1);
-		iosize = ALIGN(iosize, blocksize);
+		iosize = ALIGN(iosize, btrfs_align_size(inode));
 		sector = (em->block_start + extent_offset) >> 9;
 		bdev = em->bdev;
 		block_start = em->block_start;
@@ -3934,9 +3931,8 @@ int extent_invalidatepage(struct extent_io_tree *tree,
 	struct extent_state *cached_state = NULL;
 	u64 start = page_offset(page);
 	u64 end = start + PAGE_CACHE_SIZE - 1;
-	size_t blocksize = page->mapping->host->i_sb->s_blocksize;
 
-	start += ALIGN(offset, blocksize);
+	start += ALIGN(offset, btrfs_align_size(page->mapping->host));
 	if (start > end)
 		return 0;
 
@@ -4044,7 +4040,6 @@ static struct extent_map *get_extent_skip_holes(struct inode *inode,
 						u64 last,
 						get_extent_t *get_extent)
 {
-	u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
 	struct extent_map *em;
 	u64 len;
 
@@ -4055,7 +4050,7 @@ static struct extent_map *get_extent_skip_holes(struct inode *inode,
 		len = last - offset;
 		if (len == 0)
 			break;
-		len = ALIGN(len, sectorsize);
+		len = ALIGN(len, btrfs_align_size(inode));
 		em = get_extent(inode, NULL, 0, offset, len, 0);
 		if (IS_ERR_OR_NULL(em))
 			return em;
@@ -4119,8 +4114,8 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		return -ENOMEM;
 	path->leave_spinning = 1;
 
-	start = ALIGN(start, BTRFS_I(inode)->root->sectorsize);
-	len = ALIGN(len, BTRFS_I(inode)->root->sectorsize);
+	start = ALIGN(start, btrfs_align_size(inode));
+	len = ALIGN(len, btrfs_align_size(inode));
 
 	/*
 	 * lookup the last file extent.  We're not using i_size here
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 82d0342..1861322 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -505,8 +505,8 @@ int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
 	u64 end_pos = pos + write_bytes;
 	loff_t isize = i_size_read(inode);
 
-	start_pos = pos & ~((u64)root->sectorsize - 1);
-	num_bytes = ALIGN(write_bytes + pos - start_pos, root->sectorsize);
+	start_pos = pos & ~(btrfs_align_size(inode) - 1);
+	num_bytes = ALIGN(write_bytes + pos - start_pos, btrfs_align_size(inode));
 
 	end_of_last_block = start_pos + num_bytes - 1;
 	err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
@@ -889,7 +889,7 @@ next_slot:
 				inode_sub_bytes(inode,
 						extent_end - key.offset);
 				extent_end = ALIGN(extent_end,
-						   root->sectorsize);
+						   btrfs_align_size(inode));
 			} else if (update_refs && disk_bytenr > 0) {
 				ret = btrfs_free_extent(trans, root,
 						disk_bytenr, num_bytes, 0,
@@ -1254,7 +1254,7 @@ static noinline int prepare_pages(struct btrfs_root *root, struct file *file,
 	u64 start_pos;
 	u64 last_pos;
 
-	start_pos = pos & ~((u64)root->sectorsize - 1);
+	start_pos = pos & ~((u64)btrfs_align_size(inode) - 1);
 	last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
 
 again:
@@ -2263,11 +2263,10 @@ static long btrfs_fallocate(struct file *file, int mode,
 	u64 alloc_hint = 0;
 	u64 locked_end;
 	struct extent_map *em;
-	int blocksize = BTRFS_I(inode)->root->sectorsize;
 	int ret;
 
-	alloc_start = round_down(offset, blocksize);
-	alloc_end = round_up(offset + len, blocksize);
+	alloc_start = round_down(offset, btrfs_align_size(inode));
+	alloc_end = round_up(offset + len, btrfs_align_size(inode));
 
 	/* Make sure we aren't being give some crap mode */
 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
@@ -2367,7 +2366,7 @@ static long btrfs_fallocate(struct file *file, int mode,
 		}
 		last_byte = min(extent_map_end(em), alloc_end);
 		actual_end = min_t(u64, extent_map_end(em), offset + len);
-		last_byte = ALIGN(last_byte, blocksize);
+		last_byte = ALIGN(last_byte, btrfs_align_size(inode));
 
 		if (em->block_start == EXTENT_MAP_HOLE ||
 		    (cur_offset >= inode->i_size &&
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f1a7744..c79c9cd 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -239,7 +239,7 @@ static noinline int cow_file_range_inline(struct btrfs_root *root,
 	u64 isize = i_size_read(inode);
 	u64 actual_end = min(end + 1, isize);
 	u64 inline_len = actual_end - start;
-	u64 aligned_end = ALIGN(end, root->sectorsize);
+	u64 aligned_end = ALIGN(end, btrfs_align_size(inode));
 	u64 data_len = inline_len;
 	int ret;
 
@@ -354,7 +354,6 @@ static noinline int compress_file_range(struct inode *inode,
 {
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	u64 num_bytes;
-	u64 blocksize = root->sectorsize;
 	u64 actual_end;
 	u64 isize = i_size_read(inode);
 	int ret = 0;
@@ -407,8 +406,8 @@ again:
 	 * a compressed extent to 128k.
 	 */
 	total_compressed = min(total_compressed, max_uncompressed);
-	num_bytes = ALIGN(end - start + 1, blocksize);
-	num_bytes = max(blocksize,  num_bytes);
+	num_bytes = ALIGN(end - start + 1, btrfs_align_size(inode));
+	num_bytes = max(btrfs_align_size(inode),  num_bytes);
 	total_in = 0;
 	ret = 0;
 
@@ -508,7 +507,7 @@ cont:
 		 * up to a block size boundary so the allocator does sane
 		 * things
 		 */
-		total_compressed = ALIGN(total_compressed, blocksize);
+		total_compressed = ALIGN(total_compressed, btrfs_align_size(inode));
 
 		/*
 		 * one last check to make sure the compression is really a
@@ -837,7 +836,6 @@ static noinline int cow_file_range(struct inode *inode,
 	unsigned long ram_size;
 	u64 disk_num_bytes;
 	u64 cur_alloc_size;
-	u64 blocksize = root->sectorsize;
 	struct btrfs_key ins;
 	struct extent_map *em;
 	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
@@ -848,8 +846,8 @@ static noinline int cow_file_range(struct inode *inode,
 		return -EINVAL;
 	}
 
-	num_bytes = ALIGN(end - start + 1, blocksize);
-	num_bytes = max(blocksize,  num_bytes);
+	num_bytes = ALIGN(end - start + 1, btrfs_align_size(inode));
+	num_bytes = max(btrfs_align_size(inode), num_bytes);
 	disk_num_bytes = num_bytes;
 
 	/* if this is a small write inside eof, kick off defrag */
@@ -1263,7 +1261,7 @@ next_slot:
 		} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 			extent_end = found_key.offset +
 				btrfs_file_extent_inline_len(leaf, fi);
-			extent_end = ALIGN(extent_end, root->sectorsize);
+			extent_end = ALIGN(extent_end, btrfs_align_size(inode));
 		} else {
 			BUG_ON(1);
 		}
@@ -1389,6 +1387,12 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
 	int ret;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 
+	if (inode->i_sb->s_blocksize < PAGE_CACHE_SIZE) {
+		start &= ~(PAGE_CACHE_SIZE - 1);
+		end = max_t(u64, start + PAGE_CACHE_SIZE - 1, end);
+	}
+
+
 	if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
 		ret = run_delalloc_nocow(inode, locked_page, start, end,
 					 page_started, 1, nr_written);
@@ -3894,7 +3898,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
 	 */
 	if (root->ref_cows || root == root->fs_info->tree_root)
 		btrfs_drop_extent_cache(inode, ALIGN(new_size,
-					root->sectorsize), (u64)-1, 0);
+					btrfs_align_size(inode)), (u64)-1, 0);
 
 	/*
 	 * This function is also used to drop the items in the log tree before
@@ -3980,7 +3984,7 @@ search_again:
 					btrfs_file_extent_num_bytes(leaf, fi);
 				extent_num_bytes = ALIGN(new_size -
 						found_key.offset,
-						root->sectorsize);
+						btrfs_align_size(inode));
 				btrfs_set_file_extent_num_bytes(leaf, fi,
 							 extent_num_bytes);
 				num_dec = (orig_num_bytes -
@@ -4217,8 +4221,8 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 	struct extent_map *em = NULL;
 	struct extent_state *cached_state = NULL;
 	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-	u64 hole_start = ALIGN(oldsize, root->sectorsize);
-	u64 block_end = ALIGN(size, root->sectorsize);
+	u64 hole_start = ALIGN(oldsize, btrfs_align_size(inode));
+	u64 block_end = ALIGN(size, btrfs_align_size(inode));
 	u64 last_byte;
 	u64 cur_offset;
 	u64 hole_size;
@@ -4261,7 +4265,7 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 			break;
 		}
 		last_byte = min(extent_map_end(em), block_end);
-		last_byte = ALIGN(last_byte , root->sectorsize);
+		last_byte = ALIGN(last_byte , btrfs_align_size(inode));
 		if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
 			struct extent_map *hole_em;
 			hole_size = last_byte - cur_offset;
@@ -6001,7 +6005,7 @@ again:
 	} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
 		size_t size;
 		size = btrfs_file_extent_inline_len(leaf, item);
-		extent_end = ALIGN(extent_start + size, root->sectorsize);
+		extent_end = ALIGN(extent_start + size, btrfs_align_size(inode));
 	}
 next:
 	if (start >= extent_end) {
@@ -6074,7 +6078,7 @@ next:
 		copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
 				size - extent_offset);
 		em->start = extent_start + extent_offset;
-		em->len = ALIGN(copy_size, root->sectorsize);
+		em->len = ALIGN(copy_size, btrfs_align_size(inode));
 		em->orig_block_len = em->len;
 		em->orig_start = em->start;
 		if (compress_type) {
@@ -7967,7 +7971,6 @@ static int btrfs_getattr(struct vfsmount *mnt,
 {
 	u64 delalloc_bytes;
 	struct inode *inode = dentry->d_inode;
-	u32 blocksize = inode->i_sb->s_blocksize;
 
 	generic_fillattr(inode, stat);
 	stat->dev = BTRFS_I(inode)->root->anon_dev;
@@ -7976,8 +7979,8 @@ static int btrfs_getattr(struct vfsmount *mnt,
 	spin_lock(&BTRFS_I(inode)->lock);
 	delalloc_bytes = BTRFS_I(inode)->delalloc_bytes;
 	spin_unlock(&BTRFS_I(inode)->lock);
-	stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
-			ALIGN(delalloc_bytes, blocksize)) >> 9;
+	stat->blocks = (ALIGN(inode_get_bytes(inode), btrfs_align_size(inode)) +
+			ALIGN(delalloc_bytes, btrfs_align_size(inode))) >> 9;
 	return 0;
 }
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a111622..c41e342 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2631,7 +2631,7 @@ static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
 
 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
 {
-	u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
+	u64 bs = btrfs_align_size(inode);
 
 	if (off + len > inode->i_size || off + len < off)
 		return -EINVAL;
@@ -2698,7 +2698,7 @@ static long btrfs_ioctl_file_extent_same(struct file *file,
 	int i;
 	int ret;
 	unsigned long size;
-	u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
+	u64 bs = btrfs_align_size(src);
 	bool is_admin = capable(CAP_SYS_ADMIN);
 
 	if (!(file->f_mode & FMODE_READ))
@@ -3111,7 +3111,7 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 	struct inode *src;
 	int ret;
 	u64 len = olen;
-	u64 bs = root->fs_info->sb->s_blocksize;
+	u64 bs = btrfs_align_size(inode);
 	int same_inode = 0;
 
 	/*
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 69582d5..8d703e8 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -936,7 +936,7 @@ int btrfs_ordered_update_i_size(struct inode *inode, u64 offset,
 				     ordered->file_offset +
 				     ordered->truncated_len);
 	} else {
-		offset = ALIGN(offset, BTRFS_I(inode)->root->sectorsize);
+		offset = ALIGN(offset, btrfs_align_size(inode));
 	}
 	disk_i_size = BTRFS_I(inode)->disk_i_size;
 
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 9f7fc51..455d288 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -572,7 +572,7 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
 	} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
 		size = btrfs_file_extent_inline_len(eb, item);
 		nbytes = btrfs_file_extent_ram_bytes(eb, item);
-		extent_end = ALIGN(start + size, root->sectorsize);
+		extent_end = ALIGN(start + size, btrfs_align_size(inode));
 	} else {
 		ret = 0;
 		goto out;
