static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
{
struct super_block *sb = sdp->sd_vfs;
struct gfs2_sb *p;
struct page *page;
struct bio *bio;
page = alloc_page(GFP_NOFS);
if (unlikely(!page))
return -ENOBUFS;
ClearPageUptodate(page);
ClearPageDirty(page);
lock_page(page);
bio = bio_alloc(GFP_NOFS, 1);
bio->bi_sector = sector * (sb->s_blocksize >> 9);
bio->bi_bdev = sb->s_bdev;
bio_add_page(bio, page, PAGE_SIZE, 0);
bio->bi_end_io = end_bio_io_page;
bio->bi_private = page;
submit_bio(READ_SYNC | REQ_META, bio);
wait_on_page_locked(page);
bio_put(bio);
if (!PageUptodate(page)) {
__free_page(page);
return -EIO;
}
p = kmap(page);
gfs2_sb_in(sdp, p);
kunmap(page);
__free_page(page);
return gfs2_check_sb(sdp, silent);
}
static int init_names(struct gfs2_sbd *sdp, int silent)
{
char *proto, *table;
int error = 0;
proto = sdp->sd_args.ar_lockproto;
table = sdp->sd_args.ar_locktable;
/* Try to autodetect */
if (!proto[0] || !table[0]) {
error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
if (error)
return error;
error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
if (error)
goto out;
if (!proto[0])
proto = sdp->sd_sb.sb_lockproto;
if (!table[0])
table = sdp->sd_sb.sb_locktable;
}
static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
{
u32 hash_blocks, ind_blocks, leaf_blocks;
u32 tmp_blocks;
unsigned int x;
int error;
error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
if (error) {
if (!silent)
fs_err(sdp, "can't read superblock\n");
return error;
}
error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
if (error)
return error;
sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
GFS2_BASIC_BLOCK_SHIFT;
sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode)) / sizeof(u64);
sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header)) / sizeof(u64);
sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header)) /
sizeof(struct gfs2_quota_change);
/* Compute maximum reservation required to add a entry to a directory */
hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
sdp->sd_jbsize);
ind_blocks = 0;
for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
ind_blocks += tmp_blocks;
}
leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode);
sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
for (x = 2;; x++) {
u64 space, d;
u32 m;
space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
d = space;
m = do_div(d, sdp->sd_inptrs);
if (d != sdp->sd_heightsize[x - 1] || m)
break;
sdp->sd_heightsize[x] = space;
}
sdp->sd_max_height = x;
sdp->sd_heightsize[x] = ~0;
gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode);
sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
for (x = 2;; x++) {
u64 space, d;
u32 m;
space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
d = space;
m = do_div(d, sdp->sd_inptrs);
if (d != sdp->sd_jheightsize[x - 1] || m)
break;
sdp->sd_jheightsize[x] = space;
}
sdp->sd_max_jheight = x;
sdp->sd_jheightsize[x] = ~0;
gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
return 0;
}
