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-rw-r--r--fs/ceph/locks.c260
1 files changed, 260 insertions, 0 deletions
diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c
new file mode 100644
index 00000000000..ff4e753aae9
--- /dev/null
+++ b/fs/ceph/locks.c
@@ -0,0 +1,260 @@
+#include "ceph_debug.h"
+
+#include <linux/file.h>
+#include <linux/namei.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "pagelist.h"
+
+/**
+ * Implement fcntl and flock locking functions.
+ */
+static int ceph_lock_message(u8 lock_type, u16 operation, struct file *file,
+ u64 pid, u64 pid_ns,
+ int cmd, u64 start, u64 length, u8 wait)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ struct ceph_mds_client *mdsc =
+ &ceph_sb_to_client(inode->i_sb)->mdsc;
+ struct ceph_mds_request *req;
+ int err;
+
+ req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+ req->r_inode = igrab(inode);
+
+ dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
+ "length: %llu, wait: %d, type`: %d", (int)lock_type,
+ (int)operation, pid, start, length, wait, cmd);
+
+ req->r_args.filelock_change.rule = lock_type;
+ req->r_args.filelock_change.type = cmd;
+ req->r_args.filelock_change.pid = cpu_to_le64(pid);
+ /* This should be adjusted, but I'm not sure if
+ namespaces actually get id numbers*/
+ req->r_args.filelock_change.pid_namespace =
+ cpu_to_le64((u64)pid_ns);
+ req->r_args.filelock_change.start = cpu_to_le64(start);
+ req->r_args.filelock_change.length = cpu_to_le64(length);
+ req->r_args.filelock_change.wait = wait;
+
+ err = ceph_mdsc_do_request(mdsc, inode, req);
+ 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, pid, start, length, wait, cmd, err);
+ return err;
+}
+
+/**
+ * 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)
+{
+ u64 length;
+ u8 lock_cmd;
+ int err;
+ u8 wait = 0;
+ u16 op = CEPH_MDS_OP_SETFILELOCK;
+
+ fl->fl_nspid = get_pid(task_tgid(current));
+ dout("ceph_lock, fl_pid:%d", fl->fl_pid);
+
+ /* set wait bit as appropriate, then make command as Ceph expects it*/
+ if (F_SETLKW == cmd)
+ wait = 1;
+ if (F_GETLK == cmd)
+ op = CEPH_MDS_OP_GETFILELOCK;
+
+ 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;
+
+ if (LLONG_MAX == fl->fl_end)
+ length = 0;
+ else
+ length = fl->fl_end - fl->fl_start + 1;
+
+ err = ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
+ (u64)fl->fl_pid,
+ (u64)(unsigned long)fl->fl_nspid,
+ lock_cmd, fl->fl_start,
+ length, wait);
+ if (!err) {
+ 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,
+ (u64)fl->fl_pid,
+ (u64)(unsigned long)fl->fl_nspid,
+ CEPH_LOCK_UNLOCK, fl->fl_start,
+ length, 0);
+ dout("got %d on posix_lock_file, undid lock", err);
+ }
+ } else {
+ dout("mds returned error code %d", err);
+ }
+ return err;
+}
+
+int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
+{
+ u64 length;
+ u8 lock_cmd;
+ int err;
+ u8 wait = 1;
+
+ fl->fl_nspid = get_pid(task_tgid(current));
+ dout("ceph_flock, fl_pid:%d", fl->fl_pid);
+
+ /* set wait bit, then clear it out of cmd*/
+ if (cmd & LOCK_NB)
+ wait = 0;
+ cmd = cmd & (LOCK_SH | LOCK_EX | LOCK_UN);
+ /* set command sequence that Ceph wants to see:
+ shared lock, exclusive lock, or unlock */
+ if (LOCK_SH == cmd)
+ lock_cmd = CEPH_LOCK_SHARED;
+ else if (LOCK_EX == cmd)
+ lock_cmd = CEPH_LOCK_EXCL;
+ else
+ lock_cmd = CEPH_LOCK_UNLOCK;
+ /* 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;
+
+ err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
+ file, (u64)fl->fl_pid,
+ (u64)(unsigned long)fl->fl_nspid,
+ lock_cmd, fl->fl_start,
+ length, wait);
+ if (!err) {
+ err = flock_lock_file_wait(file, fl);
+ if (err) {
+ ceph_lock_message(CEPH_LOCK_FLOCK,
+ CEPH_MDS_OP_SETFILELOCK,
+ file, (u64)fl->fl_pid,
+ (u64)(unsigned long)fl->fl_nspid,
+ CEPH_LOCK_UNLOCK, fl->fl_start,
+ length, 0);
+ dout("got %d on flock_lock_file_wait, undid lock", err);
+ }
+ } else {
+ dout("mds error code %d", err);
+ }
+ return err;
+}
+
+/**
+ * Must be called with BKL already held. Fills in the passed
+ * counter variables, so you can prepare pagelist metadata before calling
+ * ceph_encode_locks.
+ */
+void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
+{
+ struct file_lock *lock;
+
+ *fcntl_count = 0;
+ *flock_count = 0;
+
+ for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
+ if (lock->fl_flags & FL_POSIX)
+ ++(*fcntl_count);
+ else if (lock->fl_flags & FL_FLOCK)
+ ++(*flock_count);
+ }
+ dout("counted %d flock locks and %d fcntl locks",
+ *flock_count, *fcntl_count);
+}
+
+/**
+ * Encode the flock and fcntl locks for the given inode into the pagelist.
+ * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
+ * sequential flock locks.
+ * Must be called with BLK already held, and the lock numbers should have
+ * been gathered under the same lock holding window.
+ */
+int ceph_encode_locks(struct inode *inode, struct ceph_pagelist *pagelist,
+ int num_fcntl_locks, int num_flock_locks)
+{
+ struct file_lock *lock;
+ struct ceph_filelock cephlock;
+ int err = 0;
+
+ dout("encoding %d flock and %d fcntl locks", num_flock_locks,
+ num_fcntl_locks);
+ err = ceph_pagelist_append(pagelist, &num_fcntl_locks, sizeof(u32));
+ if (err)
+ goto fail;
+ for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
+ if (lock->fl_flags & FL_POSIX) {
+ err = lock_to_ceph_filelock(lock, &cephlock);
+ if (err)
+ goto fail;
+ err = ceph_pagelist_append(pagelist, &cephlock,
+ sizeof(struct ceph_filelock));
+ }
+ if (err)
+ goto fail;
+ }
+
+ err = ceph_pagelist_append(pagelist, &num_flock_locks, sizeof(u32));
+ if (err)
+ goto fail;
+ for (lock = inode->i_flock; lock != NULL; lock = lock->fl_next) {
+ if (lock->fl_flags & FL_FLOCK) {
+ err = lock_to_ceph_filelock(lock, &cephlock);
+ if (err)
+ goto fail;
+ err = ceph_pagelist_append(pagelist, &cephlock,
+ sizeof(struct ceph_filelock));
+ }
+ if (err)
+ goto fail;
+ }
+fail:
+ return err;
+}
+
+/*
+ * Given a pointer to a lock, convert it to a ceph filelock
+ */
+int lock_to_ceph_filelock(struct file_lock *lock,
+ struct ceph_filelock *cephlock)
+{
+ int err = 0;
+
+ cephlock->start = cpu_to_le64(lock->fl_start);
+ cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
+ cephlock->client = cpu_to_le64(0);
+ cephlock->pid = cpu_to_le64(lock->fl_pid);
+ cephlock->pid_namespace =
+ cpu_to_le64((u64)(unsigned long)lock->fl_nspid);
+
+ switch (lock->fl_type) {
+ case F_RDLCK:
+ cephlock->type = CEPH_LOCK_SHARED;
+ break;
+ case F_WRLCK:
+ cephlock->type = CEPH_LOCK_EXCL;
+ break;
+ case F_UNLCK:
+ cephlock->type = CEPH_LOCK_UNLOCK;
+ break;
+ default:
+ dout("Have unknown lock type %d", lock->fl_type);
+ err = -EINVAL;
+ }
+
+ return err;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-25 13:36:35 +0000