From baab0630167f7539483af0f277aa6eeff39490d6 Mon Sep 17 00:00:00 2001 From: Andreas Dilger Date: Fri, 16 Sep 2011 03:22:00 -0600 Subject: [PATCH] zpl: Fix "df -i" to have better free inodes value Due to the confusion in Linux statfs between f_frsize and f_bsize the blocks counts were changed to be in units of z_max_blksize instead of SPA_MINBLOCKSIZE as it is on other platforms. However, the free files calculation in zfs_statvfs() is limited by the free blocks count, since each dnode consumes one block/sector. This provided a reasonable estimate of free inodes, but on Linux this meant that the free inodes count was underestimated by a large amount, since 256 512-byte dnodes can fit into a 128kB block, and more if the max blocksize is increased to 1MB or larger. Also, the use of SPA_MINBLOCKSIZE is semantically incorrect since DNODE_SIZE may change to a value other than SPA_MINBLOCKSIZE and may even change per dataset, and devices with large sectors setting ashift will also use a larger blocksize. Correct the f_ffree calculation to use (availbytes >> DNODE_SHIFT) to more accurately compute the maximum number of dnodes that can be created. Signed-off-by: Andreas Dilger Signed-off-by: Brian Behlendorf Closes #413 Closes #400 --- module/zfs/zfs_vfsops.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/module/zfs/zfs_vfsops.c b/module/zfs/zfs_vfsops.c index 31692f4379d8..0ee541358cd6 100644 --- a/module/zfs/zfs_vfsops.c +++ b/module/zfs/zfs_vfsops.c @@ -944,7 +944,7 @@ zfs_statvfs(struct dentry *dentry, struct kstatfs *statp) * For f_ffree, report the smaller of the number of object available * and the number of blocks (each object will take at least a block). */ - statp->f_ffree = MIN(availobjs, statp->f_bfree); + statp->f_ffree = MIN(availobjs, availbytes >> DNODE_SHIFT); statp->f_files = statp->f_ffree + usedobjs; statp->f_fsid.val[0] = dentry->d_sb->s_dev; statp->f_fsid.val[1] = 0;