[V20,07/19] Btrfs: subpage-blocksize: Allow mounting filesystems where sectorsize < PAGE_SIZE
diff mbox

Message ID 1467606879-14181-8-git-send-email-chandan@linux.vnet.ibm.com
State New
Headers show

Commit Message

Chandan Rajendra July 4, 2016, 4:34 a.m. UTC
This commit allows mounting filesystem instances with sectorsize smaller
than the PAGE_SIZE.

Since the code assumes that the super block is either equal to or larger
than sectorsize, this commit brings back the nodesize argument for
btrfs_find_create_tree_block() function. This change allows us to be
able to mount and use filesystems with 2048 bytes as the sectorsize.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
---
 fs/btrfs/disk-io.c     | 21 ++++++++-------------
 fs/btrfs/disk-io.h     |  2 +-
 fs/btrfs/extent-tree.c |  4 ++--
 fs/btrfs/extent_io.c   |  3 +--
 fs/btrfs/extent_io.h   |  4 ++--
 fs/btrfs/tree-log.c    |  2 +-
 fs/btrfs/volumes.c     | 10 +++-------
 7 files changed, 18 insertions(+), 28 deletions(-)

Patch
diff mbox

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 2d9e86b..0727c1c 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1099,7 +1099,7 @@  void readahead_tree_block(struct btrfs_root *root, u64 bytenr)
 	struct extent_buffer *buf = NULL;
 	struct inode *btree_inode = root->fs_info->btree_inode;
 
-	buf = btrfs_find_create_tree_block(root, bytenr);
+	buf = btrfs_find_create_tree_block(root, bytenr, root->nodesize);
 	if (IS_ERR(buf))
 		return;
 	read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
@@ -1115,7 +1115,7 @@  int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
 	struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
 	int ret;
 
-	buf = btrfs_find_create_tree_block(root, bytenr);
+	buf = btrfs_find_create_tree_block(root, bytenr, root->nodesize);
 	if (IS_ERR(buf))
 		return 0;
 
@@ -1146,12 +1146,12 @@  struct extent_buffer *btrfs_find_tree_block(struct btrfs_fs_info *fs_info,
 }
 
 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
-						 u64 bytenr)
+						 u64 bytenr, u32 blocksize)
 {
 	if (btrfs_test_is_dummy_root(root))
 		return alloc_test_extent_buffer(root->fs_info, bytenr,
-				root->nodesize);
-	return alloc_extent_buffer(root->fs_info, bytenr);
+						blocksize);
+	return alloc_extent_buffer(root->fs_info, bytenr, blocksize);
 }
 
 
@@ -1175,7 +1175,7 @@  struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 	struct extent_buffer *buf = NULL;
 	int ret;
 
-	buf = btrfs_find_create_tree_block(root, bytenr);
+	buf = btrfs_find_create_tree_block(root, bytenr, root->nodesize);
 	if (IS_ERR(buf))
 		return buf;
 
@@ -4093,17 +4093,12 @@  static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
 	 * Check sectorsize and nodesize first, other check will need it.
 	 * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
 	 */
-	if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
+	if (!is_power_of_2(sectorsize) || sectorsize < 2048 ||
 	    sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
 		printk(KERN_ERR "BTRFS: invalid sectorsize %llu\n", sectorsize);
 		ret = -EINVAL;
 	}
-	/* Only PAGE SIZE is supported yet */
-	if (sectorsize != PAGE_SIZE) {
-		printk(KERN_ERR "BTRFS: sectorsize %llu not supported yet, only support %lu\n",
-				sectorsize, PAGE_SIZE);
-		ret = -EINVAL;
-	}
+
 	if (!is_power_of_2(nodesize) || nodesize < sectorsize ||
 	    nodesize > BTRFS_MAX_METADATA_BLOCKSIZE) {
 		printk(KERN_ERR "BTRFS: invalid nodesize %llu\n", nodesize);
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index a81ff8d..aa3fb08 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -50,7 +50,7 @@  void readahead_tree_block(struct btrfs_root *root, u64 bytenr);
 int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr,
 			 int mirror_num, struct extent_buffer **eb);
 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
-						   u64 bytenr);
+						   u64 bytenr, u32 blocksize);
 void clean_tree_block(struct btrfs_trans_handle *trans,
 		      struct btrfs_fs_info *fs_info, struct extent_buffer *buf);
 int open_ctree(struct super_block *sb,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 51e514c..590d0e7 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -8226,7 +8226,7 @@  btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 {
 	struct extent_buffer *buf;
 
-	buf = btrfs_find_create_tree_block(root, bytenr);
+	buf = btrfs_find_create_tree_block(root, bytenr, root->nodesize);
 	if (IS_ERR(buf))
 		return buf;
 
@@ -8871,7 +8871,7 @@  static noinline int do_walk_down(struct btrfs_trans_handle *trans,
 
 	next = btrfs_find_tree_block(root->fs_info, bytenr);
 	if (!next) {
-		next = btrfs_find_create_tree_block(root, bytenr);
+		next = btrfs_find_create_tree_block(root, bytenr, blocksize);
 		if (IS_ERR(next))
 			return PTR_ERR(next);
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2b5fc13..0ec3b1e 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5427,9 +5427,8 @@  free_eb:
 #endif
 
 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
-					  u64 start)
+					  u64 start, unsigned long len)
 {
-	unsigned long len = fs_info->tree_root->nodesize;
 	unsigned long num_pages = num_extent_pages(start, len);
 	unsigned long i;
 	unsigned long index = start >> PAGE_SHIFT;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 9f073a1..91e7a75 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -435,7 +435,7 @@  int clear_page_blks_state(struct page *page, unsigned long blk_states,
 int test_page_blks_state(struct page *page, enum blk_state blk_state,
 			u64 start, u64 end, int check_all);
 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
-					  u64 start);
+					u64 start, unsigned long len);
 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 						  u64 start, unsigned long len);
 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
@@ -558,5 +558,5 @@  noinline u64 find_lock_delalloc_range(struct inode *inode,
 				      u64 *end, u64 max_bytes);
 #endif
 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
-					       u64 start, u32 nodesize);
+					      u64 start, u32 nodesize);
 #endif
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 5fa624c..2fac4d3 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2421,7 +2421,7 @@  static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
 		parent = path->nodes[*level];
 		root_owner = btrfs_header_owner(parent);
 
-		next = btrfs_find_create_tree_block(root, bytenr);
+		next = btrfs_find_create_tree_block(root, bytenr, blocksize);
 		if (IS_ERR(next))
 			return PTR_ERR(next);
 
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 986c2d8..d04ae40 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6600,15 +6600,11 @@  int btrfs_read_sys_array(struct btrfs_root *root)
 	u64 type;
 	struct btrfs_key key;
 
-	ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
-	/*
-	 * This will create extent buffer of nodesize, superblock size is
-	 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
-	 * overallocate but we can keep it as-is, only the first page is used.
-	 */
-	sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
+	sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
+					  BTRFS_SUPER_INFO_SIZE);
 	if (IS_ERR(sb))
 		return PTR_ERR(sb);
+
 	set_extent_buffer_uptodate(sb);
 	btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
 	/*