From: Joel Becker Date: Tue, 13 Apr 2010 06:26:12 +0000 (+0800) Subject: ocfs2: Define data structures for discontiguous block groups. X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4cbe4249d6586d5d88ef271e07302407a14c8443;p=linux-beck.git ocfs2: Define data structures for discontiguous block groups. Defines the OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG feature bit and modifies struct ocfs2_group_desc for the feature. Signed-off-by: Joel Becker Signed-off-by: Tao Ma --- diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c index 63c41e206792..9538bbe028d4 100644 --- a/fs/ocfs2/localalloc.c +++ b/fs/ocfs2/localalloc.c @@ -122,7 +122,7 @@ unsigned int ocfs2_la_default_mb(struct ocfs2_super *osb) struct super_block *sb = osb->sb; gd_mb = ocfs2_clusters_to_megabytes(osb->sb, - 8 * ocfs2_group_bitmap_size(sb)); + 8 * ocfs2_group_bitmap_size(sb, 0)); /* * This takes care of files systems with very small group diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h index d61a1521b10e..448aa8d11a97 100644 --- a/fs/ocfs2/ocfs2_fs.h +++ b/fs/ocfs2/ocfs2_fs.h @@ -165,6 +165,9 @@ /* Refcount tree support */ #define OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE 0x1000 +/* Discontigous block groups */ +#define OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG 0x2000 + /* * backup superblock flag is used to indicate that this volume * has backup superblocks. @@ -831,6 +834,13 @@ struct ocfs2_dx_leaf { struct ocfs2_dx_entry_list dl_list; }; +/* + * Largest bitmap for a block (suballocator) group in bytes. This limit + * does not affect cluster groups (global allocator). Cluster group + * bitmaps run to the end of the block. + */ +#define OCFS2_MAX_BG_BITMAP_SIZE 256 + /* * On disk allocator group structure for OCFS2 */ @@ -852,7 +862,29 @@ struct ocfs2_group_desc __le64 bg_blkno; /* Offset on disk, in blocks */ /*30*/ struct ocfs2_block_check bg_check; /* Error checking */ __le64 bg_reserved2; -/*40*/ __u8 bg_bitmap[0]; +/*40*/ union { + __u8 bg_bitmap[0]; + struct { + /* + * Block groups may be discontiguous when + * OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG is set. + * The extents of a discontigous block group are + * stored in bg_list. It is a flat list. + * l_tree_depth must always be zero. A + * discontiguous group is signified by a non-zero + * bg_list->l_next_free_rec. Only block groups + * can be discontiguous; Cluster groups cannot. + * We've never made a block group with more than + * 2048 blocks (256 bytes of bg_bitmap). This + * codifies that limit so that we can fit bg_list. + * bg_size of a discontiguous block group will + * be 256 to match bg_bitmap_filler. + */ + __u8 bg_bitmap_filler[OCFS2_MAX_BG_BITMAP_SIZE]; +/*140*/ struct ocfs2_extent_list bg_list; + }; + }; +/* Actual on-disk size is one block */ }; struct ocfs2_refcount_rec { @@ -1276,12 +1308,16 @@ static inline u16 ocfs2_local_alloc_size(struct super_block *sb) return size; } -static inline int ocfs2_group_bitmap_size(struct super_block *sb) +static inline int ocfs2_group_bitmap_size(struct super_block *sb, + int suballocator) { int size; - size = sb->s_blocksize - - offsetof(struct ocfs2_group_desc, bg_bitmap); + if (suballocator) + size = OCFS2_MAX_BG_BITMAP_SIZE; + else + size = sb->s_blocksize - + offsetof(struct ocfs2_group_desc, bg_bitmap); return size; } @@ -1404,12 +1440,15 @@ static inline int ocfs2_local_alloc_size(int blocksize) return size; } -static inline int ocfs2_group_bitmap_size(int blocksize) +static inline int ocfs2_group_bitmap_size(int blocksize, int suballocator) { int size; - size = blocksize - - offsetof(struct ocfs2_group_desc, bg_bitmap); + if (suballocator) + size = OCFS2_MAX_BG_BITMAP_SIZE; + else + size = blocksize - + offsetof(struct ocfs2_group_desc, bg_bitmap); return size; } diff --git a/fs/ocfs2/resize.c b/fs/ocfs2/resize.c index a821f667b5c4..5bbfc123781f 100644 --- a/fs/ocfs2/resize.c +++ b/fs/ocfs2/resize.c @@ -315,7 +315,7 @@ int ocfs2_group_extend(struct inode * inode, int new_clusters) BUG_ON(!OCFS2_IS_VALID_DINODE(fe)); if (le16_to_cpu(fe->id2.i_chain.cl_cpg) != - ocfs2_group_bitmap_size(osb->sb) * 8) { + ocfs2_group_bitmap_size(osb->sb, 0) * 8) { mlog(ML_ERROR, "The disk is too old and small. " "Force to do offline resize."); ret = -EINVAL; @@ -496,7 +496,7 @@ int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input) fe = (struct ocfs2_dinode *)main_bm_bh->b_data; if (le16_to_cpu(fe->id2.i_chain.cl_cpg) != - ocfs2_group_bitmap_size(osb->sb) * 8) { + ocfs2_group_bitmap_size(osb->sb, 0) * 8) { mlog(ML_ERROR, "The disk is too old and small." " Force to do offline resize."); ret = -EINVAL; diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index 667d622b3659..1070f79fa068 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -360,7 +360,7 @@ static int ocfs2_block_group_fill(handle_t *handle, memset(bg, 0, sb->s_blocksize); strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE); bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation); - bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb)); + bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1)); bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl)); bg->bg_chain = cpu_to_le16(my_chain); bg->bg_next_group = cl->cl_recs[my_chain].c_blkno; diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c index 12c2203a62fe..59930ee4fe2e 100644 --- a/fs/ocfs2/super.c +++ b/fs/ocfs2/super.c @@ -2277,7 +2277,7 @@ static int ocfs2_initialize_super(struct super_block *sb, osb->osb_clusters_at_boot = OCFS2_I(inode)->ip_clusters; iput(inode); - osb->bitmap_cpg = ocfs2_group_bitmap_size(sb) * 8; + osb->bitmap_cpg = ocfs2_group_bitmap_size(sb, 0) * 8; status = ocfs2_init_slot_info(osb); if (status < 0) {