2019-07-30 23:39:02

by Scott Mayhew

[permalink] [raw]
Subject: [nfs-utils PATCH RFC 1/2] nfsdcld: add a "GetVersion" upcall

Add a "GetVersion" upcall to allow the kernel to determine the maximum
upcall version that nfsdcld supports.

Signed-off-by: Scott Mayhew <[email protected]>
---
support/include/cld.h | 11 ++++++++-
utils/nfsdcld/cld-internal.h | 4 ++-
utils/nfsdcld/nfsdcld.c | 47 ++++++++++++++++++++++++++++++------
utils/nfsdcld/sqlite.c | 2 +-
4 files changed, 53 insertions(+), 11 deletions(-)

diff --git a/support/include/cld.h b/support/include/cld.h
index c1f5b70..00a40da 100644
--- a/support/include/cld.h
+++ b/support/include/cld.h
@@ -33,7 +33,8 @@ enum cld_command {
Cld_Remove, /* remove record of this cm_id */
Cld_Check, /* is this cm_id allowed? */
Cld_GraceDone, /* grace period is complete */
- Cld_GraceStart,
+ Cld_GraceStart, /* grace start (upload client records) */
+ Cld_GetVersion, /* query max supported upcall version */
};

/* representation of long-form NFSv4 client ID */
@@ -51,7 +52,15 @@ struct cld_msg {
union {
int64_t cm_gracetime; /* grace period start time */
struct cld_name cm_name;
+ uint8_t cm_version; /* for getting max version */
} __attribute__((packed)) cm_u;
} __attribute__((packed));

+struct cld_msg_hdr {
+ uint8_t cm_vers; /* upcall version */
+ uint8_t cm_cmd; /* upcall command */
+ int16_t cm_status; /* return code */
+ uint32_t cm_xid; /* transaction id */
+} __attribute__((packed));
+
#endif /* !_NFSD_CLD_H */
diff --git a/utils/nfsdcld/cld-internal.h b/utils/nfsdcld/cld-internal.h
index 76e97db..f33cb04 100644
--- a/utils/nfsdcld/cld-internal.h
+++ b/utils/nfsdcld/cld-internal.h
@@ -21,7 +21,9 @@
struct cld_client {
int cl_fd;
struct event cl_event;
- struct cld_msg cl_msg;
+ union {
+ struct cld_msg cl_msg;
+ } cl_u;
};

uint64_t current_epoch;
diff --git a/utils/nfsdcld/nfsdcld.c b/utils/nfsdcld/nfsdcld.c
index cbf71fc..aa5594b 100644
--- a/utils/nfsdcld/nfsdcld.c
+++ b/utils/nfsdcld/nfsdcld.c
@@ -343,7 +343,7 @@ cld_not_implemented(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

xlog(D_GENERAL, "%s: downcalling with not implemented error", __func__);

@@ -365,12 +365,40 @@ cld_not_implemented(struct cld_client *clnt)
}
}

+static void
+cld_get_version(struct cld_client *clnt)
+{
+ int ret;
+ ssize_t bsize, wsize;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;
+
+ xlog(D_GENERAL, "%s: version = %u.", __func__, UPCALL_VERSION);
+
+ cmsg->cm_u.cm_version = UPCALL_VERSION;
+ cmsg->cm_status = 0;
+
+ bsize = sizeof(*cmsg);
+
+ xlog(D_GENERAL, "Doing downcall with status %d", cmsg->cm_status);
+ wsize = atomicio((void *)write, clnt->cl_fd, cmsg, bsize);
+ if (wsize != bsize) {
+ xlog(L_ERROR, "%s: problem writing to cld pipe (%ld): %m",
+ __func__, wsize);
+ ret = cld_pipe_open(clnt);
+ if (ret) {
+ xlog(L_FATAL, "%s: unable to reopen pipe: %d",
+ __func__, ret);
+ exit(ret);
+ }
+ }
+}
+
static void
cld_create(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

ret = cld_check_grace_period();
if (ret)
@@ -406,7 +434,7 @@ cld_remove(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

ret = cld_check_grace_period();
if (ret)
@@ -442,7 +470,7 @@ cld_check(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

/*
* If we get a check upcall at all, it means we're talking to an old
@@ -489,7 +517,7 @@ cld_gracedone(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

/*
* If we got a "gracedone" upcall while we're not in grace, then
@@ -543,7 +571,7 @@ reply:
static int
gracestart_callback(struct cld_client *clnt) {
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

cmsg->cm_status = -EINPROGRESS;

@@ -562,7 +590,7 @@ cld_gracestart(struct cld_client *clnt)
{
int ret;
ssize_t bsize, wsize;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

xlog(D_GENERAL, "%s: updating grace epochs", __func__);

@@ -598,7 +626,7 @@ cldcb(int UNUSED(fd), short which, void *data)
{
ssize_t len;
struct cld_client *clnt = data;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

if (which != EV_READ)
goto out;
@@ -633,6 +661,9 @@ cldcb(int UNUSED(fd), short which, void *data)
case Cld_GraceStart:
cld_gracestart(clnt);
break;
+ case Cld_GetVersion:
+ cld_get_version(clnt);
+ break;
default:
xlog(L_WARNING, "%s: command %u is not yet implemented",
__func__, cmsg->cm_cmd);
diff --git a/utils/nfsdcld/sqlite.c b/utils/nfsdcld/sqlite.c
index fa81df8..6525fc1 100644
--- a/utils/nfsdcld/sqlite.c
+++ b/utils/nfsdcld/sqlite.c
@@ -1152,7 +1152,7 @@ sqlite_iterate_recovery(int (*cb)(struct cld_client *clnt), struct cld_client *c
{
int ret;
sqlite3_stmt *stmt = NULL;
- struct cld_msg *cmsg = &clnt->cl_msg;
+ struct cld_msg *cmsg = &clnt->cl_u.cl_msg;

if (recovery_epoch == 0) {
xlog(D_GENERAL, "%s: not in grace!", __func__);
--
2.17.2