diff options
author | Sage Weil <sage@newdream.net> | 2009-10-06 11:31:06 -0700 |
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committer | Sage Weil <sage@newdream.net> | 2009-10-06 11:31:06 -0700 |
commit | 0dee3c28af2fbe22ca62739a7f57da5435d35793 (patch) | |
tree | dd5992a4abc86c5931ce36258b972dbf48ab355d /fs/ceph/ceph_fs.c | |
parent | 7ad920b504a980adcab4d3f6b85695526e6fd7bb (diff) |
ceph: on-wire types
These headers describe the types used to exchange messages between the
Ceph client and various servers. All types are little-endian and
packed. These headers are shared between the kernel and userspace, so
all types are in terms of e.g. __u32.
Additionally, we define a few magic values to identify the current
version of the protocol(s) in use, so that discrepancies to be
detected on mount.
Signed-off-by: Sage Weil <sage@newdream.net>
Diffstat (limited to 'fs/ceph/ceph_fs.c')
-rw-r--r-- | fs/ceph/ceph_fs.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/fs/ceph/ceph_fs.c b/fs/ceph/ceph_fs.c new file mode 100644 index 000000000000..9371ff1c0002 --- /dev/null +++ b/fs/ceph/ceph_fs.c @@ -0,0 +1,80 @@ +/* + * Some non-inline ceph helpers + */ +#include "types.h" + +int ceph_flags_to_mode(int flags) +{ +#ifdef O_DIRECTORY /* fixme */ + if ((flags & O_DIRECTORY) == O_DIRECTORY) + return CEPH_FILE_MODE_PIN; +#endif +#ifdef O_LAZY + if (flags & O_LAZY) + return CEPH_FILE_MODE_LAZY; +#endif + if ((flags & O_APPEND) == O_APPEND) + flags |= O_WRONLY; + + flags &= O_ACCMODE; + if ((flags & O_RDWR) == O_RDWR) + return CEPH_FILE_MODE_RDWR; + if ((flags & O_WRONLY) == O_WRONLY) + return CEPH_FILE_MODE_WR; + return CEPH_FILE_MODE_RD; +} + +int ceph_caps_for_mode(int mode) +{ + switch (mode) { + case CEPH_FILE_MODE_PIN: + return CEPH_CAP_PIN; + case CEPH_FILE_MODE_RD: + return CEPH_CAP_PIN | CEPH_CAP_FILE_SHARED | + CEPH_CAP_FILE_RD | CEPH_CAP_FILE_CACHE; + case CEPH_FILE_MODE_RDWR: + return CEPH_CAP_PIN | CEPH_CAP_FILE_SHARED | + CEPH_CAP_FILE_EXCL | + CEPH_CAP_FILE_RD | CEPH_CAP_FILE_CACHE | + CEPH_CAP_FILE_WR | CEPH_CAP_FILE_BUFFER | + CEPH_CAP_AUTH_SHARED | CEPH_CAP_AUTH_EXCL | + CEPH_CAP_XATTR_SHARED | CEPH_CAP_XATTR_EXCL; + case CEPH_FILE_MODE_WR: + return CEPH_CAP_PIN | CEPH_CAP_FILE_SHARED | + CEPH_CAP_FILE_EXCL | + CEPH_CAP_FILE_WR | CEPH_CAP_FILE_BUFFER | + CEPH_CAP_AUTH_SHARED | CEPH_CAP_AUTH_EXCL | + CEPH_CAP_XATTR_SHARED | CEPH_CAP_XATTR_EXCL; + } + return 0; +} + +/* Name hashing routines. Initial hash value */ +/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */ +#define ceph_init_name_hash() 0 + +/* partial hash update function. Assume roughly 4 bits per character */ +static unsigned long ceph_partial_name_hash(unsigned long c, + unsigned long prevhash) +{ + return (prevhash + (c << 4) + (c >> 4)) * 11; +} + +/* + * Finally: cut down the number of bits to a int value (and try to avoid + * losing bits) + */ +static unsigned long ceph_end_name_hash(unsigned long hash) +{ + return hash & 0xffffffff; +} + +/* Compute the hash for a name string. */ +unsigned int ceph_full_name_hash(const char *name, unsigned int len) +{ + unsigned long hash = ceph_init_name_hash(); + while (len--) + hash = ceph_partial_name_hash(*name++, hash); + return ceph_end_name_hash(hash); +} + |