This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / fs / dlm / rcom.c
diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c
new file mode 100644 (file)
index 0000000..6bfbd61
--- /dev/null
@@ -0,0 +1,525 @@
+/******************************************************************************
+*******************************************************************************
+**
+**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
+**  Copyright (C) 2005 Red Hat, Inc.  All rights reserved.
+**
+**  This copyrighted material is made available to anyone wishing to use,
+**  modify, copy, or redistribute it subject to the terms and conditions
+**  of the GNU General Public License v.2.
+**
+*******************************************************************************
+******************************************************************************/
+
+#include "dlm_internal.h"
+#include "lockspace.h"
+#include "member.h"
+#include "lowcomms.h"
+#include "midcomms.h"
+#include "rcom.h"
+#include "recover.h"
+#include "dir.h"
+#include "config.h"
+#include "memory.h"
+#include "lock.h"
+#include "util.h"
+
+
+static int rcom_response(struct dlm_ls *ls)
+{
+       return test_bit(LSFL_RCOM_READY, &ls->ls_flags);
+}
+
+static int create_rcom(struct dlm_ls *ls, int to_nodeid, int type, int len,
+                      struct dlm_rcom **rc_ret, struct dlm_mhandle **mh_ret)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       char *mb;
+       int mb_len = sizeof(struct dlm_rcom) + len;
+
+       mh = dlm_lowcomms_get_buffer(to_nodeid, mb_len, GFP_KERNEL, &mb);
+       if (!mh) {
+               log_print("create_rcom to %d type %d len %d ENOBUFS",
+                         to_nodeid, type, len);
+               return -ENOBUFS;
+       }
+       memset(mb, 0, mb_len);
+
+       rc = (struct dlm_rcom *) mb;
+
+       rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
+       rc->rc_header.h_lockspace = ls->ls_global_id;
+       rc->rc_header.h_nodeid = dlm_our_nodeid();
+       rc->rc_header.h_length = mb_len;
+       rc->rc_header.h_cmd = DLM_RCOM;
+
+       rc->rc_type = type;
+
+       spin_lock(&ls->ls_recover_lock);
+       rc->rc_seq = ls->ls_recover_seq;
+       spin_unlock(&ls->ls_recover_lock);
+
+       *mh_ret = mh;
+       *rc_ret = rc;
+       return 0;
+}
+
+static void send_rcom(struct dlm_ls *ls, struct dlm_mhandle *mh,
+                     struct dlm_rcom *rc)
+{
+       dlm_rcom_out(rc);
+       dlm_lowcomms_commit_buffer(mh);
+}
+
+/* When replying to a status request, a node also sends back its
+   configuration values.  The requesting node then checks that the remote
+   node is configured the same way as itself. */
+
+static void make_config(struct dlm_ls *ls, struct rcom_config *rf)
+{
+       rf->rf_lvblen = ls->ls_lvblen;
+       rf->rf_lsflags = ls->ls_exflags;
+}
+
+static int check_config(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
+{
+       struct rcom_config *rf = (struct rcom_config *) rc->rc_buf;
+
+       if ((rc->rc_header.h_version & 0xFFFF0000) != DLM_HEADER_MAJOR) {
+               log_error(ls, "version mismatch: %x nodeid %d: %x",
+                         DLM_HEADER_MAJOR | DLM_HEADER_MINOR, nodeid,
+                         rc->rc_header.h_version);
+               return -EINVAL;
+       }
+
+       if (rf->rf_lvblen != ls->ls_lvblen ||
+           rf->rf_lsflags != ls->ls_exflags) {
+               log_error(ls, "config mismatch: %d,%x nodeid %d: %d,%x",
+                         ls->ls_lvblen, ls->ls_exflags,
+                         nodeid, rf->rf_lvblen, rf->rf_lsflags);
+               return -EINVAL;
+       }
+       return 0;
+}
+
+static void allow_sync_reply(struct dlm_ls *ls, uint64_t *new_seq)
+{
+       spin_lock(&ls->ls_rcom_spin);
+       *new_seq = ++ls->ls_rcom_seq;
+       set_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
+       spin_unlock(&ls->ls_rcom_spin);
+}
+
+static void disallow_sync_reply(struct dlm_ls *ls)
+{
+       spin_lock(&ls->ls_rcom_spin);
+       clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
+       clear_bit(LSFL_RCOM_READY, &ls->ls_flags);
+       spin_unlock(&ls->ls_rcom_spin);
+}
+
+int dlm_rcom_status(struct dlm_ls *ls, int nodeid)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error = 0;
+
+       ls->ls_recover_nodeid = nodeid;
+
+       if (nodeid == dlm_our_nodeid()) {
+               rc = (struct dlm_rcom *) ls->ls_recover_buf;
+               rc->rc_result = dlm_recover_status(ls);
+               goto out;
+       }
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_STATUS, 0, &rc, &mh);
+       if (error)
+               goto out;
+
+       allow_sync_reply(ls, &rc->rc_id);
+       memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
+
+       send_rcom(ls, mh, rc);
+
+       error = dlm_wait_function(ls, &rcom_response);
+       disallow_sync_reply(ls);
+       if (error)
+               goto out;
+
+       rc = (struct dlm_rcom *) ls->ls_recover_buf;
+
+       if (rc->rc_result == -ESRCH) {
+               /* we pretend the remote lockspace exists with 0 status */
+               log_debug(ls, "remote node %d not ready", nodeid);
+               rc->rc_result = 0;
+       } else
+               error = check_config(ls, rc, nodeid);
+       /* the caller looks at rc_result for the remote recovery status */
+ out:
+       return error;
+}
+
+static void receive_rcom_status(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error, nodeid = rc_in->rc_header.h_nodeid;
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_STATUS_REPLY,
+                           sizeof(struct rcom_config), &rc, &mh);
+       if (error)
+               return;
+       rc->rc_id = rc_in->rc_id;
+       rc->rc_seq_reply = rc_in->rc_seq;
+       rc->rc_result = dlm_recover_status(ls);
+       make_config(ls, (struct rcom_config *) rc->rc_buf);
+
+       send_rcom(ls, mh, rc);
+}
+
+static void receive_sync_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       spin_lock(&ls->ls_rcom_spin);
+       if (!test_bit(LSFL_RCOM_WAIT, &ls->ls_flags) ||
+           rc_in->rc_id != ls->ls_rcom_seq) {
+               log_debug(ls, "reject reply %d from %d seq %llx expect %llx",
+                         rc_in->rc_type, rc_in->rc_header.h_nodeid,
+                         (unsigned long long)rc_in->rc_id,
+                         (unsigned long long)ls->ls_rcom_seq);
+               goto out;
+       }
+       memcpy(ls->ls_recover_buf, rc_in, rc_in->rc_header.h_length);
+       set_bit(LSFL_RCOM_READY, &ls->ls_flags);
+       clear_bit(LSFL_RCOM_WAIT, &ls->ls_flags);
+       wake_up(&ls->ls_wait_general);
+ out:
+       spin_unlock(&ls->ls_rcom_spin);
+}
+
+static void receive_rcom_status_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       receive_sync_reply(ls, rc_in);
+}
+
+int dlm_rcom_names(struct dlm_ls *ls, int nodeid, char *last_name, int last_len)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error = 0, len = sizeof(struct dlm_rcom);
+
+       ls->ls_recover_nodeid = nodeid;
+
+       if (nodeid == dlm_our_nodeid()) {
+               dlm_copy_master_names(ls, last_name, last_len,
+                                     ls->ls_recover_buf + len,
+                                     dlm_config.ci_buffer_size - len, nodeid);
+               goto out;
+       }
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_NAMES, last_len, &rc, &mh);
+       if (error)
+               goto out;
+       memcpy(rc->rc_buf, last_name, last_len);
+
+       allow_sync_reply(ls, &rc->rc_id);
+       memset(ls->ls_recover_buf, 0, dlm_config.ci_buffer_size);
+
+       send_rcom(ls, mh, rc);
+
+       error = dlm_wait_function(ls, &rcom_response);
+       disallow_sync_reply(ls);
+ out:
+       return error;
+}
+
+static void receive_rcom_names(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error, inlen, outlen, nodeid;
+
+       nodeid = rc_in->rc_header.h_nodeid;
+       inlen = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
+       outlen = dlm_config.ci_buffer_size - sizeof(struct dlm_rcom);
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_NAMES_REPLY, outlen, &rc, &mh);
+       if (error)
+               return;
+       rc->rc_id = rc_in->rc_id;
+       rc->rc_seq_reply = rc_in->rc_seq;
+
+       dlm_copy_master_names(ls, rc_in->rc_buf, inlen, rc->rc_buf, outlen,
+                             nodeid);
+       send_rcom(ls, mh, rc);
+}
+
+static void receive_rcom_names_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       receive_sync_reply(ls, rc_in);
+}
+
+int dlm_send_rcom_lookup(struct dlm_rsb *r, int dir_nodeid)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       struct dlm_ls *ls = r->res_ls;
+       int error;
+
+       error = create_rcom(ls, dir_nodeid, DLM_RCOM_LOOKUP, r->res_length,
+                           &rc, &mh);
+       if (error)
+               goto out;
+       memcpy(rc->rc_buf, r->res_name, r->res_length);
+       rc->rc_id = (unsigned long) r;
+
+       send_rcom(ls, mh, rc);
+ out:
+       return error;
+}
+
+static void receive_rcom_lookup(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error, ret_nodeid, nodeid = rc_in->rc_header.h_nodeid;
+       int len = rc_in->rc_header.h_length - sizeof(struct dlm_rcom);
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_LOOKUP_REPLY, 0, &rc, &mh);
+       if (error)
+               return;
+
+       error = dlm_dir_lookup(ls, nodeid, rc_in->rc_buf, len, &ret_nodeid);
+       if (error)
+               ret_nodeid = error;
+       rc->rc_result = ret_nodeid;
+       rc->rc_id = rc_in->rc_id;
+       rc->rc_seq_reply = rc_in->rc_seq;
+
+       send_rcom(ls, mh, rc);
+}
+
+static void receive_rcom_lookup_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       dlm_recover_master_reply(ls, rc_in);
+}
+
+static void pack_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb,
+                          struct rcom_lock *rl)
+{
+       memset(rl, 0, sizeof(*rl));
+
+       rl->rl_ownpid = lkb->lkb_ownpid;
+       rl->rl_lkid = lkb->lkb_id;
+       rl->rl_exflags = lkb->lkb_exflags;
+       rl->rl_flags = lkb->lkb_flags;
+       rl->rl_lvbseq = lkb->lkb_lvbseq;
+       rl->rl_rqmode = lkb->lkb_rqmode;
+       rl->rl_grmode = lkb->lkb_grmode;
+       rl->rl_status = lkb->lkb_status;
+       rl->rl_wait_type = lkb->lkb_wait_type;
+
+       if (lkb->lkb_bastaddr)
+               rl->rl_asts |= AST_BAST;
+       if (lkb->lkb_astaddr)
+               rl->rl_asts |= AST_COMP;
+
+       rl->rl_namelen = r->res_length;
+       memcpy(rl->rl_name, r->res_name, r->res_length);
+
+       /* FIXME: might we have an lvb without DLM_LKF_VALBLK set ?
+          If so, receive_rcom_lock_args() won't take this copy. */
+
+       if (lkb->lkb_lvbptr)
+               memcpy(rl->rl_lvb, lkb->lkb_lvbptr, r->res_ls->ls_lvblen);
+}
+
+int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
+{
+       struct dlm_ls *ls = r->res_ls;
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       struct rcom_lock *rl;
+       int error, len = sizeof(struct rcom_lock);
+
+       if (lkb->lkb_lvbptr)
+               len += ls->ls_lvblen;
+
+       error = create_rcom(ls, r->res_nodeid, DLM_RCOM_LOCK, len, &rc, &mh);
+       if (error)
+               goto out;
+
+       rl = (struct rcom_lock *) rc->rc_buf;
+       pack_rcom_lock(r, lkb, rl);
+       rc->rc_id = (unsigned long) r;
+
+       send_rcom(ls, mh, rc);
+ out:
+       return error;
+}
+
+static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       struct dlm_rcom *rc;
+       struct dlm_mhandle *mh;
+       int error, nodeid = rc_in->rc_header.h_nodeid;
+
+       dlm_recover_master_copy(ls, rc_in);
+
+       error = create_rcom(ls, nodeid, DLM_RCOM_LOCK_REPLY,
+                           sizeof(struct rcom_lock), &rc, &mh);
+       if (error)
+               return;
+
+       /* We send back the same rcom_lock struct we received, but
+          dlm_recover_master_copy() has filled in rl_remid and rl_result */
+
+       memcpy(rc->rc_buf, rc_in->rc_buf, sizeof(struct rcom_lock));
+       rc->rc_id = rc_in->rc_id;
+       rc->rc_seq_reply = rc_in->rc_seq;
+
+       send_rcom(ls, mh, rc);
+}
+
+static void receive_rcom_lock_reply(struct dlm_ls *ls, struct dlm_rcom *rc_in)
+{
+       dlm_recover_process_copy(ls, rc_in);
+}
+
+static int send_ls_not_ready(int nodeid, struct dlm_rcom *rc_in)
+{
+       struct dlm_rcom *rc;
+       struct rcom_config *rf;
+       struct dlm_mhandle *mh;
+       char *mb;
+       int mb_len = sizeof(struct dlm_rcom) + sizeof(struct rcom_config);
+
+       mh = dlm_lowcomms_get_buffer(nodeid, mb_len, GFP_KERNEL, &mb);
+       if (!mh)
+               return -ENOBUFS;
+       memset(mb, 0, mb_len);
+
+       rc = (struct dlm_rcom *) mb;
+
+       rc->rc_header.h_version = (DLM_HEADER_MAJOR | DLM_HEADER_MINOR);
+       rc->rc_header.h_lockspace = rc_in->rc_header.h_lockspace;
+       rc->rc_header.h_nodeid = dlm_our_nodeid();
+       rc->rc_header.h_length = mb_len;
+       rc->rc_header.h_cmd = DLM_RCOM;
+
+       rc->rc_type = DLM_RCOM_STATUS_REPLY;
+       rc->rc_id = rc_in->rc_id;
+       rc->rc_seq_reply = rc_in->rc_seq;
+       rc->rc_result = -ESRCH;
+
+       rf = (struct rcom_config *) rc->rc_buf;
+       rf->rf_lvblen = -1;
+
+       dlm_rcom_out(rc);
+       dlm_lowcomms_commit_buffer(mh);
+
+       return 0;
+}
+
+static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)
+{
+       uint64_t seq;
+       int rv = 0;
+
+       switch (rc->rc_type) {
+       case DLM_RCOM_STATUS_REPLY:
+       case DLM_RCOM_NAMES_REPLY:
+       case DLM_RCOM_LOOKUP_REPLY:
+       case DLM_RCOM_LOCK_REPLY:
+               spin_lock(&ls->ls_recover_lock);
+               seq = ls->ls_recover_seq;
+               spin_unlock(&ls->ls_recover_lock);
+               if (rc->rc_seq_reply != seq) {
+                       log_debug(ls, "ignoring old reply %x from %d "
+                                     "seq_reply %llx expect %llx",
+                                     rc->rc_type, rc->rc_header.h_nodeid,
+                                     (unsigned long long)rc->rc_seq_reply,
+                                     (unsigned long long)seq);
+                       rv = 1;
+               }
+       }
+       return rv;
+}
+
+/* Called by dlm_recvd; corresponds to dlm_receive_message() but special
+   recovery-only comms are sent through here. */
+
+void dlm_receive_rcom(struct dlm_header *hd, int nodeid)
+{
+       struct dlm_rcom *rc = (struct dlm_rcom *) hd;
+       struct dlm_ls *ls;
+
+       dlm_rcom_in(rc);
+
+       /* If the lockspace doesn't exist then still send a status message
+          back; it's possible that it just doesn't have its global_id yet. */
+
+       ls = dlm_find_lockspace_global(hd->h_lockspace);
+       if (!ls) {
+               log_print("lockspace %x from %d type %x not found",
+                         hd->h_lockspace, nodeid, rc->rc_type);
+               if (rc->rc_type == DLM_RCOM_STATUS)
+                       send_ls_not_ready(nodeid, rc);
+               return;
+       }
+
+       if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
+               log_debug(ls, "ignoring recovery message %x from %d",
+                         rc->rc_type, nodeid);
+               goto out;
+       }
+
+       if (is_old_reply(ls, rc))
+               goto out;
+
+       if (nodeid != rc->rc_header.h_nodeid) {
+               log_error(ls, "bad rcom nodeid %d from %d",
+                         rc->rc_header.h_nodeid, nodeid);
+               goto out;
+       }
+
+       switch (rc->rc_type) {
+       case DLM_RCOM_STATUS:
+               receive_rcom_status(ls, rc);
+               break;
+
+       case DLM_RCOM_NAMES:
+               receive_rcom_names(ls, rc);
+               break;
+
+       case DLM_RCOM_LOOKUP:
+               receive_rcom_lookup(ls, rc);
+               break;
+
+       case DLM_RCOM_LOCK:
+               receive_rcom_lock(ls, rc);
+               break;
+
+       case DLM_RCOM_STATUS_REPLY:
+               receive_rcom_status_reply(ls, rc);
+               break;
+
+       case DLM_RCOM_NAMES_REPLY:
+               receive_rcom_names_reply(ls, rc);
+               break;
+
+       case DLM_RCOM_LOOKUP_REPLY:
+               receive_rcom_lookup_reply(ls, rc);
+               break;
+
+       case DLM_RCOM_LOCK_REPLY:
+               receive_rcom_lock_reply(ls, rc);
+               break;
+
+       default:
+               DLM_ASSERT(0, printk("rc_type=%x\n", rc->rc_type););
+       }
+ out:
+       dlm_put_lockspace(ls);
+}
+