diff options
| -rw-r--r-- | fs/ocfs2/super.c | 68 |
1 files changed, 40 insertions, 28 deletions
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c index a100b48..c3c89e2 100644 --- a/fs/ocfs2/super.c +++ b/fs/ocfs2/super.c @@ -316,39 +316,51 @@ static void ocfs2_destroy_inode(struct inode *inode) kmem_cache_free(ocfs2_inode_cachep, OCFS2_I(inode)); } -/* From xfs_super.c:xfs_max_file_offset - * Copyright (c) 2000-2004 Silicon Graphics, Inc. - */ -static unsigned long long ocfs2_max_file_offset(unsigned int blockshift) +static unsigned long long ocfs2_max_file_offset(unsigned int bbits, + unsigned int cbits) { - unsigned int pagefactor = 1; - unsigned int bitshift = BITS_PER_LONG - 1; - - /* Figure out maximum filesize, on Linux this can depend on - * the filesystem blocksize (on 32 bit platforms). - * __block_prepare_write does this in an [unsigned] long... - * page->index << (PAGE_CACHE_SHIFT - bbits) - * So, for page sized blocks (4K on 32 bit platforms), - * this wraps at around 8Tb (hence MAX_LFS_FILESIZE which is - * (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) - * but for smaller blocksizes it is less (bbits = log2 bsize). - * Note1: get_block_t takes a long (implicit cast from above) - * Note2: The Large Block Device (LBD and HAVE_SECTOR_T) patch - * can optionally convert the [unsigned] long from above into - * an [unsigned] long long. + unsigned int bytes = 1 << cbits; + unsigned int trim = bytes; + unsigned int bitshift = 32; + + /* + * i_size and all block offsets in ocfs2 are always 64 bits + * wide. i_clusters is 32 bits, in cluster-sized units. So on + * 64 bit platforms, cluster size will be the limiting factor. */ #if BITS_PER_LONG == 32 # if defined(CONFIG_LBD) BUILD_BUG_ON(sizeof(sector_t) != 8); - pagefactor = PAGE_CACHE_SIZE; - bitshift = BITS_PER_LONG; + /* + * We might be limited by page cache size. + */ + if (bytes > PAGE_CACHE_SIZE) { + bytes = PAGE_CACHE_SIZE; + trim = 1; + /* + * Shift by 31 here so that we don't get larger than + * MAX_LFS_FILESIZE + */ + bitshift = 31; + } # else - pagefactor = PAGE_CACHE_SIZE >> (PAGE_CACHE_SHIFT - blockshift); + /* + * We are limited by the size of sector_t. Use block size, as + * that's what we expose to the VFS. + */ + bytes = 1 << bbits; + trim = 1; + bitshift = 31; # endif #endif - return (((unsigned long long)pagefactor) << bitshift) - 1; + /* + * Trim by a whole cluster when we can actually approach the + * on-disk limits. Otherwise we can overflow i_clusters when + * an extent start is at the max offset. + */ + return (((unsigned long long)bytes) << bitshift) - trim; } static int ocfs2_remount(struct super_block *sb, int *flags, char *data) @@ -1259,8 +1271,8 @@ static int ocfs2_initialize_super(struct super_block *sb, int sector_size) { int status = 0; - int i; - struct ocfs2_dinode *di = NULL; + int i, cbits, bbits; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data; struct inode *inode = NULL; struct buffer_head *bitmap_bh = NULL; struct ocfs2_journal *journal; @@ -1281,7 +1293,9 @@ static int ocfs2_initialize_super(struct super_block *sb, sb->s_export_op = &ocfs2_export_ops; sb->s_flags |= MS_NOATIME; /* this is needed to support O_LARGEFILE */ - sb->s_maxbytes = ocfs2_max_file_offset(sb->s_blocksize_bits); + cbits = le32_to_cpu(di->id2.i_super.s_clustersize_bits); + bbits = le32_to_cpu(di->id2.i_super.s_blocksize_bits); + sb->s_maxbytes = ocfs2_max_file_offset(bbits, cbits); osb->sb = sb; /* Save off for ocfs2_rw_direct */ @@ -1341,8 +1355,6 @@ static int ocfs2_initialize_super(struct super_block *sb, goto bail; } - di = (struct ocfs2_dinode *)bh->b_data; - osb->max_slots = le16_to_cpu(di->id2.i_super.s_max_slots); if (osb->max_slots > OCFS2_MAX_SLOTS || osb->max_slots == 0) { mlog(ML_ERROR, "Invalid number of node slots (%u)\n", |
