[PATCH] knfsd: add some new fsid types
Add support for using a filesystem UUID to identify and export point in the
filehandle.
For NFSv2, this UUID is xor-ed down to 4 or 8 bytes so that it doesn't take up
too much room. For NFSv3+, we use the full 16 bytes, and possibly also a
64bit inode number for exports beneath the root of a filesystem.
When generating an fsid to return in 'stat' information, use the UUID (hashed
down to size) if it is available and a small 'fsid' was not specifically
provided.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/nfsd/nfsfh.h b/include/linux/nfsd/nfsfh.h
index d9c6c38..11e568e 100644
--- a/include/linux/nfsd/nfsfh.h
+++ b/include/linux/nfsd/nfsfh.h
@@ -165,38 +165,91 @@
} svc_fh;
-static inline void mk_fsid_v0(u32 *fsidv, dev_t dev, ino_t ino)
-{
- fsidv[0] = htonl((MAJOR(dev)<<16) |
- MINOR(dev));
- fsidv[1] = ino_t_to_u32(ino);
-}
+enum nfsd_fsid {
+ FSID_DEV = 0,
+ FSID_NUM,
+ FSID_MAJOR_MINOR,
+ FSID_ENCODE_DEV,
+ FSID_UUID4_INUM,
+ FSID_UUID8,
+ FSID_UUID16,
+ FSID_UUID16_INUM,
+};
-static inline void mk_fsid_v1(u32 *fsidv, u32 fsid)
-{
- fsidv[0] = fsid;
-}
+enum fsid_source {
+ FSIDSOURCE_DEV,
+ FSIDSOURCE_FSID,
+ FSIDSOURCE_UUID,
+};
+extern enum fsid_source fsid_source(struct svc_fh *fhp);
-static inline void mk_fsid_v2(u32 *fsidv, dev_t dev, ino_t ino)
-{
- fsidv[0] = htonl(MAJOR(dev));
- fsidv[1] = htonl(MINOR(dev));
- fsidv[2] = ino_t_to_u32(ino);
-}
-static inline void mk_fsid_v3(u32 *fsidv, dev_t dev, ino_t ino)
+/* This might look a little large to "inline" but in all calls except
+ * one, 'vers' is constant so moste of the function disappears.
+ */
+static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
+ u32 fsid, unsigned char *uuid)
{
- fsidv[0] = new_encode_dev(dev);
- fsidv[1] = ino_t_to_u32(ino);
+ u32 *up;
+ switch(vers) {
+ case FSID_DEV:
+ fsidv[0] = htonl((MAJOR(dev)<<16) |
+ MINOR(dev));
+ fsidv[1] = ino_t_to_u32(ino);
+ break;
+ case FSID_NUM:
+ fsidv[0] = fsid;
+ break;
+ case FSID_MAJOR_MINOR:
+ fsidv[0] = htonl(MAJOR(dev));
+ fsidv[1] = htonl(MINOR(dev));
+ fsidv[2] = ino_t_to_u32(ino);
+ break;
+
+ case FSID_ENCODE_DEV:
+ fsidv[0] = new_encode_dev(dev);
+ fsidv[1] = ino_t_to_u32(ino);
+ break;
+
+ case FSID_UUID4_INUM:
+ /* 4 byte fsid and inode number */
+ up = (u32*)uuid;
+ fsidv[0] = ino_t_to_u32(ino);
+ fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
+ break;
+
+ case FSID_UUID8:
+ /* 8 byte fsid */
+ up = (u32*)uuid;
+ fsidv[0] = up[0] ^ up[2];
+ fsidv[1] = up[1] ^ up[3];
+ break;
+
+ case FSID_UUID16:
+ /* 16 byte fsid - NFSv3+ only */
+ memcpy(fsidv, uuid, 16);
+ break;
+
+ case FSID_UUID16_INUM:
+ /* 8 byte inode and 16 byte fsid */
+ *(u64*)fsidv = (u64)ino;
+ memcpy(fsidv+2, uuid, 16);
+ break;
+ default: BUG();
+ }
}
static inline int key_len(int type)
{
switch(type) {
- case 0: return 8;
- case 1: return 4;
- case 2: return 12;
- case 3: return 8;
+ case FSID_DEV: return 8;
+ case FSID_NUM: return 4;
+ case FSID_MAJOR_MINOR: return 12;
+ case FSID_ENCODE_DEV: return 8;
+ case FSID_UUID4_INUM: return 8;
+ case FSID_UUID8: return 8;
+ case FSID_UUID16: return 16;
+ case FSID_UUID16_INUM: return 24;
default: return 0;
}
}