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authorYehuda Sadeh <yehuda@hq.newdream.net>2010-04-07 02:14:15 +0400
committerSage Weil <sage@newdream.net>2010-10-21 02:37:28 +0400
commit3d14c5d2b6e15c21d8e5467dc62d33127c23a644 (patch)
tree7d123c47847df9d1e865b6b78dc7da3fe739b704 /fs/ceph/ceph_hash.c
parentae1533b62b3369e6ae32338f4a77d64d0e88f676 (diff)
downloadlinux-3d14c5d2b6e15c21d8e5467dc62d33127c23a644.tar.xz
ceph: factor out libceph from Ceph file system
This factors out protocol and low-level storage parts of ceph into a separate libceph module living in net/ceph and include/linux/ceph. This is mostly a matter of moving files around. However, a few key pieces of the interface change as well: - ceph_client becomes ceph_fs_client and ceph_client, where the latter captures the mon and osd clients, and the fs_client gets the mds client and file system specific pieces. - Mount option parsing and debugfs setup is correspondingly broken into two pieces. - The mon client gets a generic handler callback for otherwise unknown messages (mds map, in this case). - The basic supported/required feature bits can be expanded (and are by ceph_fs_client). No functional change, aside from some subtle error handling cases that got cleaned up in the refactoring process. Signed-off-by: Sage Weil <sage@newdream.net>
Diffstat (limited to 'fs/ceph/ceph_hash.c')
-rw-r--r--fs/ceph/ceph_hash.c118
1 files changed, 0 insertions, 118 deletions
diff --git a/fs/ceph/ceph_hash.c b/fs/ceph/ceph_hash.c
deleted file mode 100644
index bd570015d147..000000000000
--- a/fs/ceph/ceph_hash.c
+++ /dev/null
@@ -1,118 +0,0 @@
-
-#include "types.h"
-
-/*
- * Robert Jenkin's hash function.
- * http://burtleburtle.net/bob/hash/evahash.html
- * This is in the public domain.
- */
-#define mix(a, b, c) \
- do { \
- a = a - b; a = a - c; a = a ^ (c >> 13); \
- b = b - c; b = b - a; b = b ^ (a << 8); \
- c = c - a; c = c - b; c = c ^ (b >> 13); \
- a = a - b; a = a - c; a = a ^ (c >> 12); \
- b = b - c; b = b - a; b = b ^ (a << 16); \
- c = c - a; c = c - b; c = c ^ (b >> 5); \
- a = a - b; a = a - c; a = a ^ (c >> 3); \
- b = b - c; b = b - a; b = b ^ (a << 10); \
- c = c - a; c = c - b; c = c ^ (b >> 15); \
- } while (0)
-
-unsigned ceph_str_hash_rjenkins(const char *str, unsigned length)
-{
- const unsigned char *k = (const unsigned char *)str;
- __u32 a, b, c; /* the internal state */
- __u32 len; /* how many key bytes still need mixing */
-
- /* Set up the internal state */
- len = length;
- a = 0x9e3779b9; /* the golden ratio; an arbitrary value */
- b = a;
- c = 0; /* variable initialization of internal state */
-
- /* handle most of the key */
- while (len >= 12) {
- a = a + (k[0] + ((__u32)k[1] << 8) + ((__u32)k[2] << 16) +
- ((__u32)k[3] << 24));
- b = b + (k[4] + ((__u32)k[5] << 8) + ((__u32)k[6] << 16) +
- ((__u32)k[7] << 24));
- c = c + (k[8] + ((__u32)k[9] << 8) + ((__u32)k[10] << 16) +
- ((__u32)k[11] << 24));
- mix(a, b, c);
- k = k + 12;
- len = len - 12;
- }
-
- /* handle the last 11 bytes */
- c = c + length;
- switch (len) { /* all the case statements fall through */
- case 11:
- c = c + ((__u32)k[10] << 24);
- case 10:
- c = c + ((__u32)k[9] << 16);
- case 9:
- c = c + ((__u32)k[8] << 8);
- /* the first byte of c is reserved for the length */
- case 8:
- b = b + ((__u32)k[7] << 24);
- case 7:
- b = b + ((__u32)k[6] << 16);
- case 6:
- b = b + ((__u32)k[5] << 8);
- case 5:
- b = b + k[4];
- case 4:
- a = a + ((__u32)k[3] << 24);
- case 3:
- a = a + ((__u32)k[2] << 16);
- case 2:
- a = a + ((__u32)k[1] << 8);
- case 1:
- a = a + k[0];
- /* case 0: nothing left to add */
- }
- mix(a, b, c);
-
- return c;
-}
-
-/*
- * linux dcache hash
- */
-unsigned ceph_str_hash_linux(const char *str, unsigned length)
-{
- unsigned long hash = 0;
- unsigned char c;
-
- while (length--) {
- c = *str++;
- hash = (hash + (c << 4) + (c >> 4)) * 11;
- }
- return hash;
-}
-
-
-unsigned ceph_str_hash(int type, const char *s, unsigned len)
-{
- switch (type) {
- case CEPH_STR_HASH_LINUX:
- return ceph_str_hash_linux(s, len);
- case CEPH_STR_HASH_RJENKINS:
- return ceph_str_hash_rjenkins(s, len);
- default:
- return -1;
- }
-}
-
-const char *ceph_str_hash_name(int type)
-{
- switch (type) {
- case CEPH_STR_HASH_LINUX:
- return "linux";
- case CEPH_STR_HASH_RJENKINS:
- return "rjenkins";
- default:
- return "unknown";
- }
-}