btrfs-progs: btrfs-convert: Allow setting nodesize

Allow btrfs-convert to use nodesizes other than 4096. It defaults to
max(16384, pagesize), like mkfs.

Signed-off-by: Sebastian Thorarensen <sebth@naju.se>
Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/Documentation/btrfs-convert.txt b/Documentation/btrfs-convert.txt
index 6a9e1de..89b2fbd 100644 (file)
--- a/Documentation/btrfs-convert.txt
+++ b/Documentation/btrfs-convert.txt
@@ -23,6 +23,10 @@ Disable data checksum.
 Ignore xattrs and ACLs.
 -n::
 Disable packing of small files.
+-N <SIZE>::
+Set filesystem nodesize, the tree block size in which btrfs stores data.
+The default value is 16KB (16384) or the page size, whichever is bigger.
+Must be a multiple of the sectorsize, but not larger than 65536.
 -r::
 Roll back to ext2fs.
 -l <LABEL>::

diff --git a/btrfs-convert.c b/btrfs-convert.c
index 205eaf5..0123654 100644 (file)
--- a/btrfs-convert.c
+++ b/btrfs-convert.c
@@ -141,6 +141,25 @@ static int ext2_alloc_block(ext2_filsys fs, u64 goal, u64 *block_ret)
        return -ENOSPC;
 }
 
+static int ext2_alloc_block_range(ext2_filsys fs, u64 goal, int num,
+               u64 *block_ret)
+{
+       blk_t block;
+       ext2fs_block_bitmap bitmap = fs->block_map;
+       blk_t start = ext2fs_get_block_bitmap_start(bitmap);
+       blk_t end = ext2fs_get_block_bitmap_end(bitmap);
+
+       for (block = max_t(u64, goal, start); block + num < end; block++) {
+               if (ext2fs_fast_test_block_bitmap_range(bitmap, block, num)) {
+                       ext2fs_fast_mark_block_bitmap_range(bitmap, block,
+                                       num);
+                       *block_ret = block;
+                       return 0;
+               }
+       }
+       return -ENOSPC;
+}
+
 static int ext2_free_block(ext2_filsys fs, u64 block)
 {
        BUG_ON(block != (blk_t)block);
@@ -148,6 +167,13 @@ static int ext2_free_block(ext2_filsys fs, u64 block)
        return 0;
 }
 
+static int ext2_free_block_range(ext2_filsys fs, u64 block, int num)
+{
+       BUG_ON(block != (blk_t)block);
+       ext2fs_fast_unmark_block_bitmap_range(fs->block_map, block, num);
+       return 0;
+}
+
 static int cache_free_extents(struct btrfs_root *root, ext2_filsys ext2_fs)
 
 {
@@ -2233,9 +2259,9 @@ err:
 }
 
 static int do_convert(const char *devname, int datacsum, int packing, int noxattr,
-              int copylabel, const char *fslabel, int progress)
+               u32 nodesize, int copylabel, const char *fslabel, int progress)
 {
-       int i, ret;
+       int i, ret, blocks_per_node;
        int fd = -1;
        u32 blocksize;
        u64 blocks[7];
@@ -2262,8 +2288,17 @@ static int do_convert(const char *devname, int datacsum, int packing, int noxatt
                fprintf(stderr, "filetype feature is missing\n");
                goto fail;
        }
+       if (btrfs_check_node_or_leaf_size(nodesize, blocksize))
+               goto fail;
+       blocks_per_node = nodesize / blocksize;
+       ret = -blocks_per_node;
        for (i = 0; i < 7; i++) {
-               ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
+               if (nodesize == blocksize)
+                       ret = ext2_alloc_block(ext2_fs, 0, blocks + i);
+               else
+                       ret = ext2_alloc_block_range(ext2_fs,
+                                       ret + blocks_per_node, blocks_per_node,
+                                       blocks + i);
                if (ret) {
                        fprintf(stderr, "not enough free space\n");
                        goto fail;
@@ -2277,7 +2312,7 @@ static int do_convert(const char *devname, int datacsum, int packing, int noxatt
                goto fail;
        }
        ret = make_btrfs(fd, devname, ext2_fs->super->s_volume_name,
-                        NULL, blocks, total_bytes, blocksize, blocksize,
+                        NULL, blocks, total_bytes, nodesize, nodesize,
                         blocksize, blocksize, 0);
        if (ret) {
                fprintf(stderr, "unable to create initial ctree: %s\n",
@@ -2304,7 +2339,11 @@ static int do_convert(const char *devname, int datacsum, int packing, int noxatt
        /* recover block allocation bitmap */
        for (i = 0; i < 7; i++) {
                blocks[i] /= blocksize;
-               ext2_free_block(ext2_fs, blocks[i]);
+               if (nodesize == blocksize)
+                       ext2_free_block(ext2_fs, blocks[i]);
+               else
+                       ext2_free_block_range(ext2_fs, blocks[i],
+                                       blocks_per_node);
        }
        ret = init_btrfs(root);
        if (ret) {
@@ -2764,6 +2803,7 @@ static void print_usage(void)
        printf("\t-d             disable data checksum\n");
        printf("\t-i             ignore xattrs and ACLs\n");
        printf("\t-n             disable packing of small files\n");
+       printf("\t-N SIZE        set filesystem nodesize\n");
        printf("\t-r             roll back to ext2fs\n");
        printf("\t-l LABEL       set filesystem label\n");
        printf("\t-L             use label from converted fs\n");
@@ -2777,6 +2817,8 @@ int main(int argc, char *argv[])
        int packing = 1;
        int noxattr = 0;
        int datacsum = 1;
+       u32 nodesize = max_t(u32, sysconf(_SC_PAGESIZE),
+                       BTRFS_MKFS_DEFAULT_NODE_SIZE);
        int rollback = 0;
        int copylabel = 0;
        int usage_error = 0;
@@ -2791,7 +2833,7 @@ int main(int argc, char *argv[])
                        { "no-progress", no_argument, NULL, GETOPT_VAL_IEC},
                        { NULL, 0, NULL, 0 }
                };
-               int c = getopt_long(argc, argv, "dinrl:Lp", long_options,
+               int c = getopt_long(argc, argv, "dinN:rl:Lp", long_options,
                                &long_index);
 
                if (c < 0)
@@ -2806,6 +2848,9 @@ int main(int argc, char *argv[])
                        case 'n':
                                packing = 0;
                                break;
+                       case 'N':
+                               nodesize = parse_size(optarg);
+                               break;
                        case 'r':
                                rollback = 1;
                                break;
@@ -2865,7 +2910,8 @@ int main(int argc, char *argv[])
        if (rollback) {
                ret = do_rollback(file);
        } else {
-               ret = do_convert(file, datacsum, packing, noxattr, copylabel, fslabel, progress);
+               ret = do_convert(file, datacsum, packing, noxattr, nodesize,
+                               copylabel, fslabel, progress);
        }
        if (ret)
                return 1;