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#include <linux/ceph/ceph_debug.h>
#include <linux/file.h>
#include <linux/namei.h>
#include <linux/random.h>
#include "super.h"
#include "mds_client.h"
#include <linux/ceph/pagelist.h>
static u64 lock_secret;
static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req);
static inline u64 secure_addr(void *addr)
{
u64 v = lock_secret ^ (u64)(unsigned long)addr;
/*
* Set the most significant bit, so that MDS knows the 'owner'
* is sufficient to identify the owner of lock. (old code uses
* both 'owner' and 'pid')
*/
v |= (1ULL << 63);
return v;
}
void __init ceph_flock_init(void)
{
get_random_bytes(&lock_secret, sizeof(lock_secret));
}
/**
* Implement fcntl and flock locking functions.
*/
static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
int cmd, u8 wait, struct file_lock *fl)
{
struct inode *inode = file_inode(file);
struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
struct ceph_mds_request *req;
int err;
u64 length = 0;
u64 owner;
if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK)
wait = 0;
req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
req->r_inode = inode;
ihold(inode);
req->r_num_caps = 1;
/* mds requires start and length rather than start and end */
if (LLONG_MAX == fl->fl_end)
length = 0;
else
length = fl->fl_end - fl->fl_start + 1;
owner = secure_addr(fl->fl_owner);
dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
"start: %llu, length: %llu, wait: %d, type: %d", (int)lock_type,
(int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
wait, fl->fl_type);
req->r_args.filelock_change.rule = lock_type;
req->r_args.filelock_change.type = cmd;
req->r_args.filelock_change.owner = cpu_to_le64(owner);
req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
req->r_args.filelock_change.length = cpu_to_le64(length);
req->r_args.filelock_change.wait = wait;
if (wait)
req->r_wait_for_completion = ceph_lock_wait_for_completion;
err = ceph_mdsc_do_request(mdsc, inode, req);
if (operation == CEPH_MDS_OP_GETFILELOCK) {
fl->fl_pid = le64_to_cpu(req->r_reply_info.filelock_reply->pid);
if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
fl->fl_type = F_RDLCK;
else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
fl->fl_type = F_WRLCK;
else
fl->fl_type = F_UNLCK;
fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
le64_to_cpu(req->r_reply_info.filelock_reply->length);
if (length >= 1)
fl->fl_end = length -1;
else
fl->fl_end = 0;
}
ceph_mdsc_put_request(req);
dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
"length: %llu, wait: %d, type: %d, err code %d", (int)lock_type,
(int)operation, (u64)fl->fl_pid, fl->fl_start,
length, wait, fl->fl_type, err);
return err;
}
static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
struct ceph_mds_request *req)
{
struct ceph_mds_request *intr_req;
struct inode *inode = req->r_inode;
int err, lock_type;
BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
lock_type = CEPH_LOCK_FCNTL_INTR;
else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
lock_type = CEPH_LOCK_FLOCK_INTR;
else
BUG_ON(1);
BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);
err = wait_for_completion_interruptible(&req->r_completion);
if (!err)
return 0;
dout("ceph_lock_wait_for_completion: request %llu was interrupted\n",
req->r_tid);
intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
USE_AUTH_MDS);
if (IS_ERR(intr_req))
return PTR_ERR(intr_req);
intr_req->r_inode = inode;
ihold(inode);
intr_req->r_num_caps = 1;
intr_req->r_args.filelock_change = req->r_args.filelock_change;
intr_req->r_args.filelock_change.rule = lock_type;
intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;
err = ceph_mdsc_do_request(mdsc, inode, intr_req);
ceph_mdsc_put_request(intr_req);
if (err && err != -ERESTARTSYS)
return err;
wait_for_completion(&req->r_completion);
return 0;
}
/**
* Attempt to set an fcntl lock.
* For now, this just goes away to the server. Later it may be more awesome.
*/
int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
{
u8 lock_cmd;
int err;
u8 wait = 0;
u16 op = CEPH_MDS_OP_SETFILELOCK;
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
/* No mandatory locks */
if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
return -ENOLCK;
dout("ceph_lock, fl_owner: %p", fl->fl_owner);
/* set wait bit as appropriate, then make command as Ceph expects it*/
if (IS_GETLK(cmd))
op = CEPH_MDS_OP_GETFILELOCK;
else if (IS_SETLKW(cmd))
wait = 1;
if (F_RDLCK == fl->fl_type)
lock_cmd = CEPH_LOCK_SHARED;
else if (F_WRLCK == fl->fl_type)
lock_cmd = CEPH_LOCK_EXCL;
else
lock_cmd = CEPH_LOCK_UNLOCK;
err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file, lock_cmd, wait, fl);
if (!err) {
if (op != CEPH_MDS_OP_GETFILELOCK) {
dout("mds locked, locking locally");
err = posix_lock_file(file, fl, NULL);
if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
/* undo! This should only happen if
* the kernel detects local
* deadlock. */
ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
CEPH_LOCK_UNLOCK, 0, fl);
dout("got %d on posix_lock_file, undid lock",
err);
}
}
}
return err;
}
int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
{
u8 lock_cmd;
int err;
u8 wait = 0;
if (!(fl->fl_flags & FL_FLOCK))
return -ENOLCK;
/* No mandatory locks */
if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
return -ENOLCK;
dout("ceph_flock, fl_file: %p", fl->fl_file);
if (IS_SETLKW(cmd))
wait = 1;
if (F_RDLCK == fl->fl_type)
lock_cmd = CEPH_LOCK_SHARED;
else if (F_WRLCK == fl->fl_type)
lock_cmd = CEPH_LOCK_EXCL;
else
lock_cmd = CEPH_LOCK_UNLOCK;
err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
file, lock_cmd, wait, fl);
if (!err) {
err = flock_lock_file_wait(
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