From ecc30c79157103e8bd7492043ee992b763443832 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 28 Jan 2008 10:37:35 +0000 Subject: [GFS2] Streamline indirect pointer tree height calculation This patch improves the calculation of the tree height in order to reduce the number of operations which are carried out on each call to gfs2_block_map. In the common case, we now make a single comparison, rather than calculating the required tree height from scratch each time. Also in the case that the tree does need some extra height, we start from the current height rather from zero when we work out what the new height ought to be. In addition the di_height field is moved into the inode proper and reduced in size to a u8 since the value must be between 0 and GFS2_MAX_META_HEIGHT (10). Signed-off-by: Steven Whitehouse --- fs/gfs2/inode.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) (limited to 'fs/gfs2/inode.c') diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 37725ade3c51..ff66ab7a17c8 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -248,12 +248,10 @@ static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf) { struct gfs2_dinode_host *di = &ip->i_di; const struct gfs2_dinode *str = buf; + u16 height; - if (ip->i_no_addr != be64_to_cpu(str->di_num.no_addr)) { - if (gfs2_consist_inode(ip)) - gfs2_dinode_print(ip); - return -EIO; - } + if (unlikely(ip->i_no_addr != be64_to_cpu(str->di_num.no_addr))) + goto corrupt; ip->i_no_formal_ino = be64_to_cpu(str->di_num.no_formal_ino); ip->i_inode.i_mode = be32_to_cpu(str->di_mode); ip->i_inode.i_rdev = 0; @@ -290,7 +288,10 @@ static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf) di->di_flags = be32_to_cpu(str->di_flags); gfs2_set_inode_flags(&ip->i_inode); - di->di_height = be16_to_cpu(str->di_height); + height = be16_to_cpu(str->di_height); + if (unlikely(height > GFS2_MAX_META_HEIGHT)) + goto corrupt; + ip->i_height = (u8)height; di->di_depth = be16_to_cpu(str->di_depth); di->di_entries = be32_to_cpu(str->di_entries); @@ -300,6 +301,10 @@ static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf) gfs2_set_aops(&ip->i_inode); return 0; +corrupt: + if (gfs2_consist_inode(ip)) + gfs2_dinode_print(ip); + return -EIO; } /** @@ -1401,7 +1406,7 @@ void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf) str->di_generation = cpu_to_be64(di->di_generation); str->di_flags = cpu_to_be32(di->di_flags); - str->di_height = cpu_to_be16(di->di_height); + str->di_height = cpu_to_be16(ip->i_height); str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) && !(ip->i_di.di_flags & GFS2_DIF_EXHASH) ? GFS2_FORMAT_DE : 0); @@ -1430,7 +1435,6 @@ void gfs2_dinode_print(const struct gfs2_inode *ip) printk(KERN_INFO " di_goal_data = %llu\n", (unsigned long long)di->di_goal_data); printk(KERN_INFO " di_flags = 0x%.8X\n", di->di_flags); - printk(KERN_INFO " di_height = %u\n", di->di_height); printk(KERN_INFO " di_depth = %u\n", di->di_depth); printk(KERN_INFO " di_entries = %u\n", di->di_entries); printk(KERN_INFO " di_eattr = %llu\n", -- cgit v1.2.3-58-ga151