xfs: Extend project quotas to support 32bit project ids

This patch adds support for 32bit project quota identifiers.

On disk format is backward compatible with 16bit projid numbers. projid
on disk is now kept in two 16bit values - di_projid_lo (which holds the
same position as old 16bit projid value) and new di_projid_hi (takes
existing padding) and converts from/to 32bit value on the fly.

xfs_admin (for existing fs), mkfs.xfs (for new fs) needs to be used
to enable PROJID32BIT support.

Signed-off-by: Arkadiusz Miśkiewicz <arekm@maven.pl>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

1 files changed, 23 insertions, 3 deletions

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index ac82327ec9db..fac52290de90 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -134,8 +134,9 @@ typedef struct xfs_icdinode {
         __uint32_t      di_uid;         /* owner's user id */
         __uint32_t      di_gid;         /* owner's group id */
         __uint32_t      di_nlink;       /* number of links to file */
-        __uint16_t      di_projid;      /* owner's project id */
-        __uint8_t       di_pad[8];      /* unused, zeroed space */
+        __uint16_t      di_projid_lo;   /* lower part of owner's project id */
+        __uint16_t      di_projid_hi;   /* higher part of owner's project id */
+        __uint8_t       di_pad[6];      /* unused, zeroed space */
         __uint16_t      di_flushiter;   /* incremented on flush */
         xfs_ictimestamp_t di_atime;     /* time last accessed */
         xfs_ictimestamp_t di_mtime;     /* time last modified */
@@ -334,6 +335,25 @@ xfs_iflags_test_and_clear(xfs_inode_t *ip, unsigned short flags)
 }
 
 /*
+ * Project quota id helpers (previously projid was 16bit only
+ * and using two 16bit values to hold new 32bit projid was choosen
+ * to retain compatibility with "old" filesystems).
+ */
+static inline prid_t
+xfs_get_projid(struct xfs_inode *ip)
+{
+        return (prid_t)ip->i_d.di_projid_hi << 16 | ip->i_d.di_projid_lo;
+}
+
+static inline void
+xfs_set_projid(struct xfs_inode *ip,
+                prid_t projid)
+{
+        ip->i_d.di_projid_hi = (__uint16_t) (projid >> 16);
+        ip->i_d.di_projid_lo = (__uint16_t) (projid & 0xffff);
+}
+
+/*
  * Manage the i_flush queue embedded in the inode.  This completion
  * queue synchronizes processes attempting to flush the in-core
  * inode back to disk.
@@ -455,7 +475,7 @@ void		xfs_inode_free(struct xfs_inode *ip);
  * xfs_inode.c prototypes.
  */
 int             xfs_ialloc(struct xfs_trans *, xfs_inode_t *, mode_t,
-                           xfs_nlink_t, xfs_dev_t, xfs_prid_t, int,
+                           xfs_nlink_t, xfs_dev_t, prid_t, int,
                            struct xfs_buf **, boolean_t *, xfs_inode_t **);
 
 uint            xfs_ip2xflags(struct xfs_inode *);