From 479965d66e320f1a095bb76027171daa675a9c72 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 15 Oct 2007 16:14:27 -0400 Subject: Btrfs: Optimizations for the extent_buffer code Signed-off-by: Chris Mason diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index f60920e..9427b79 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -464,22 +464,12 @@ static int check_block(struct btrfs_root *root, struct btrfs_path *path, int level) { struct extent_buffer *buf = path->nodes[level]; - char fsid[BTRFS_FSID_SIZE]; - read_extent_buffer(buf, fsid, (unsigned long)btrfs_header_fsid(buf), - BTRFS_FSID_SIZE); - - if (memcmp(fsid, root->fs_info->fsid, BTRFS_FSID_SIZE)) { - int i = 0; + if (memcmp_extent_buffer(buf, root->fs_info->fsid, + (unsigned long)btrfs_header_fsid(buf), + BTRFS_FSID_SIZE)) { printk("warning bad block %Lu\n", buf->start); - if (!btrfs_buffer_uptodate(buf)) { - WARN_ON(1); - } - for (i = 0; i < BTRFS_FSID_SIZE; i++) { - printk("%x:%x ", root->fs_info->fsid[i], fsid[i]); - } - printk("\n"); - // BUG(); + BUG(); } if (level == 0) return check_leaf(root, path, level); @@ -504,13 +494,14 @@ static int generic_bin_search(struct extent_buffer *eb, unsigned long p, int high = max; int mid; int ret; - struct btrfs_disk_key *tmp; + struct btrfs_disk_key *tmp = NULL; struct btrfs_disk_key unaligned; unsigned long offset; char *map_token = NULL; char *kaddr = NULL; unsigned long map_start = 0; unsigned long map_len = 0; + int err; while(low < high) { mid = (low + high) / 2; @@ -519,19 +510,24 @@ static int generic_bin_search(struct extent_buffer *eb, unsigned long p, if (!map_token || offset < map_start || (offset + sizeof(struct btrfs_disk_key)) > map_start + map_len) { - if (map_token) + if (map_token) { unmap_extent_buffer(eb, map_token, KM_USER0); - map_extent_buffer(eb, offset, &map_token, &kaddr, - &map_start, &map_len, KM_USER0); + map_token = NULL; + } + err = map_extent_buffer(eb, offset, + sizeof(struct btrfs_disk_key), + &map_token, &kaddr, + &map_start, &map_len, KM_USER0); + + if (!err) { + tmp = (struct btrfs_disk_key *)(kaddr + offset - + map_start); + } else { + read_extent_buffer(eb, &unaligned, + offset, sizeof(unaligned)); + tmp = &unaligned; + } - } - if (offset + sizeof(struct btrfs_disk_key) > - map_start + map_len) { - unmap_extent_buffer(eb, map_token, KM_USER0); - read_extent_buffer(eb, &unaligned, - offset, sizeof(unaligned)); - map_token = NULL; - tmp = &unaligned; } else { tmp = (struct btrfs_disk_key *)(kaddr + offset - map_start); @@ -544,7 +540,8 @@ static int generic_bin_search(struct extent_buffer *eb, unsigned long p, high = mid; else { *slot = mid; - unmap_extent_buffer(eb, map_token, KM_USER0); + if (map_token) + unmap_extent_buffer(eb, map_token, KM_USER0); return 0; } } diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index c4b8298..30fbbd7 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -22,6 +22,7 @@ #include #include #include +#include #include "bit-radix.h" #include "extent_map.h" @@ -431,15 +432,52 @@ struct btrfs_root { static inline u##bits btrfs_##name(struct extent_buffer *eb, \ type *s) \ { \ - __le##bits res; \ - read_eb_member(eb, s, type, member, &res); \ - return le##bits##_to_cpu(res); \ + int err; \ + char *map_token; \ + char *kaddr; \ + unsigned long map_start; \ + unsigned long map_len; \ + unsigned long offset = (unsigned long)s + \ + offsetof(type, member); \ + err = map_extent_buffer(eb, offset, \ + sizeof(((type *)0)->member), \ + &map_token, &kaddr, \ + &map_start, &map_len, KM_USER0); \ + if (!err) { \ + __le##bits *tmp = (__le##bits *)(kaddr + offset - \ + map_start); \ + u##bits res = le##bits##_to_cpu(*tmp); \ + unmap_extent_buffer(eb, map_token, KM_USER0); \ + return res; \ + } else { \ + __le##bits res; \ + read_eb_member(eb, s, type, member, &res); \ + return le##bits##_to_cpu(res); \ + } \ } \ static inline void btrfs_set_##name(struct extent_buffer *eb, \ type *s, u##bits val) \ { \ - val = cpu_to_le##bits(val); \ - write_eb_member(eb, s, type, member, &val); \ + int err; \ + char *map_token; \ + char *kaddr; \ + unsigned long map_start; \ + unsigned long map_len; \ + unsigned long offset = (unsigned long)s + \ + offsetof(type, member); \ + err = map_extent_buffer(eb, offset, \ + sizeof(((type *)0)->member), \ + &map_token, &kaddr, \ + &map_start, &map_len, KM_USER0); \ + if (!err) { \ + __le##bits *tmp = (__le##bits *)(kaddr + offset - \ + map_start); \ + *tmp = cpu_to_le##bits(val); \ + unmap_extent_buffer(eb, map_token, KM_USER0); \ + } else { \ + val = cpu_to_le##bits(val); \ + write_eb_member(eb, s, type, member, &val); \ + } \ } #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits) \ diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 55fefdf..8bef309 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -2140,14 +2140,20 @@ void read_extent_buffer(struct extent_buffer *eb, void *dstv, EXPORT_SYMBOL(read_extent_buffer); int map_extent_buffer(struct extent_buffer *eb, unsigned long start, + unsigned long min_len, char **token, char **map, unsigned long *map_start, unsigned long *map_len, int km) { - size_t offset; + size_t offset = start & (PAGE_CACHE_SIZE - 1); char *kaddr; size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT; + unsigned long end_i = (start_offset + start + min_len) >> + PAGE_CACHE_SHIFT; + + if (i != end_i) + return -EINVAL; WARN_ON(start > eb->len); @@ -2155,8 +2161,7 @@ int map_extent_buffer(struct extent_buffer *eb, unsigned long start, offset = start_offset; *map_start = 0; } else { - offset = 0; - *map_start = (i << PAGE_CACHE_SHIFT) - offset; + *map_start = (i << PAGE_CACHE_SHIFT) - start_offset; } // kaddr = kmap_atomic(eb->pages[i], km); diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index 430b997..8957890 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -173,7 +173,7 @@ int set_extent_buffer_uptodate(struct extent_map_tree *tree, int extent_buffer_uptodate(struct extent_map_tree *tree, struct extent_buffer *eb); int map_extent_buffer(struct extent_buffer *eb, unsigned long offset, - char **token, char **map, + unsigned long min_len, char **token, char **map, unsigned long *map_start, unsigned long *map_len, int km); void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km); -- cgit v0.10.2