From b6cda9bcb4df7544c67fc3548a53bc1607d59f46 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 14 Dec 2007 15:30:32 -0500 Subject: [PATCH] Btrfs: Add mount -o nodatasum to turn of file data checksumming Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 14 ++++++++------ fs/btrfs/disk-io.c | 1 + fs/btrfs/inode.c | 11 ++++++++++- fs/btrfs/super.c | 17 +++++++++++++++-- 4 files changed, 34 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 052555ced44d..5e255cabfd10 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -321,6 +321,7 @@ struct btrfs_fs_info { u64 generation; u64 last_trans_committed; + unsigned long mount_opt; struct btrfs_transaction *running_transaction; struct btrfs_super_block super_copy; struct extent_buffer *sb_buffer; @@ -429,6 +430,13 @@ struct btrfs_root { */ #define BTRFS_STRING_ITEM_KEY 253 +#define BTRFS_MOUNT_NODATASUM 0x1 + +#define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt) +#define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt) +#define btrfs_test_opt(root, opt) ((root)->fs_info->mount_opt & \ + BTRFS_MOUNT_##opt) + /* some macros to generate set/get funcs for the struct fields. This * assumes there is a lefoo_to_cpu for every type, so lets make a simple * one for u8: @@ -906,12 +914,6 @@ static inline u32 btrfs_level_size(struct btrfs_root *root, int level) { ((unsigned long)(btrfs_leaf_data(leaf) + \ btrfs_item_offset_nr(leaf, slot))) -/* mount option defines and helpers */ -#define BTRFS_MOUNT_SUBVOL 0x000001 -#define btrfs_clear_opt(o, opt) o &= ~BTRFS_MOUNT_##opt -#define btrfs_set_opt(o, opt) o |= BTRFS_MOUNT_##opt -#define btrfs_test_opt(sb, opt) (BTRFS_SB(sb)->s_mount_opt & \ - BTRFS_MOUNT_##opt) /* extent-tree.c */ int btrfs_extent_post_op(struct btrfs_trans_handle *trans, struct btrfs_root *root); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 60a30da6af00..4338b00c2a25 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -568,6 +568,7 @@ struct btrfs_root *open_ctree(struct super_block *sb) fs_info->tree_root = tree_root; fs_info->extent_root = extent_root; fs_info->sb = sb; + fs_info->mount_opt = 0; fs_info->btree_inode = new_inode(sb); fs_info->btree_inode->i_ino = 1; fs_info->btree_inode->i_nlink = 1; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index e535c50e669b..11885cb114e2 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -116,10 +116,13 @@ int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end) struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; char *kaddr; - int ret; + int ret = 0; u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT; size_t offset = start - page_start; + if (btrfs_test_opt(root, NODATASUM)) + return 0; + mutex_lock(&root->fs_info->fs_mutex); trans = btrfs_start_transaction(root, 1); btrfs_set_trans_block_group(trans, inode); @@ -143,6 +146,9 @@ int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end) struct btrfs_path *path = NULL; u32 csum; + if (btrfs_test_opt(root, NODATASUM)) + return 0; + mutex_lock(&root->fs_info->fs_mutex); path = btrfs_alloc_path(); item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0); @@ -176,6 +182,9 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end) u32 csum = ~(u32)0; unsigned long flags; + if (btrfs_test_opt(root, NODATASUM)) + return 0; + ret = get_state_private(em_tree, start, &private); local_irq_save(flags); kaddr = kmap_atomic(page, KM_IRQ0); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index ffa02872c4d6..ad4f280ec777 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -61,11 +61,12 @@ static void btrfs_put_super (struct super_block * sb) } enum { - Opt_subvol, Opt_err, + Opt_subvol, Opt_nodatasum, Opt_err, }; static match_table_t tokens = { {Opt_subvol, "subvol=%s"}, + {Opt_nodatasum, "nodatasum"}, {Opt_err, NULL} }; @@ -74,7 +75,12 @@ static int parse_options (char * options, char **subvol_name) { char * p; + struct btrfs_fs_info *info = NULL; substring_t args[MAX_OPT_ARGS]; + + if (root) + info = root->fs_info; + if (!options) return 1; @@ -86,7 +92,12 @@ static int parse_options (char * options, token = match_token(p, tokens, args); switch (token) { case Opt_subvol: - *subvol_name = match_strdup(&args[0]); + if (subvol_name) + *subvol_name = match_strdup(&args[0]); + break; + case Opt_nodatasum: + if (root) + btrfs_set_opt(info->mount_opt, NODATASUM); break; default: return 0; @@ -143,6 +154,8 @@ static int btrfs_fill_super(struct super_block * sb, void * data, int silent) goto fail_close; } + parse_options((char *)data, tree_root, NULL); + /* this does the super kobj at the same time */ err = btrfs_sysfs_add_super(tree_root->fs_info); if (err)