nfsd: add a tracepoint for nfsd_setattr

Turn Sargun's internal kprobe based implementation of this into a normal
static tracepoint. Also, remove the dprintk's that got added recently
with the fix for zero-length ACLs.

Cc: Sargun Dillon <[e-mail]>
Signed-off-by: Jeff Layton <[e-mail]>
Signed-off-by: Chuck Lever <[e-mail]>

fs/nfsd/trace.h

···
 #include <linux/tracepoint.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/xprt.h>
+#include <trace/misc/fs.h>
 #include <trace/misc/nfs.h>
 #include <trace/misc/sunrpc.h>
 
···
 
 DEFINE_COPY_ASYNC_DONE_EVENT(done);
 DEFINE_COPY_ASYNC_DONE_EVENT(cancel);
+
+TRACE_EVENT(nfsd_vfs_setattr,
+	TP_PROTO(
+		const struct svc_rqst *rqstp,
+		const struct svc_fh *fhp,
+		const struct iattr *iap,
+		const struct timespec64 *guardtime
+	),
+	TP_ARGS(rqstp, fhp, iap, guardtime),
+	TP_STRUCT__entry(
+		NFSD_TRACE_PROC_CALL_FIELDS(rqstp)
+		__field(u32, fh_hash)
+		__field(s64, gtime_tv_sec)
+		__field(u32, gtime_tv_nsec)
+		__field(unsigned int, ia_valid)
+		__field(loff_t, ia_size)
+		__field(uid_t, ia_uid)
+		__field(gid_t, ia_gid)
+		__field(umode_t, ia_mode)
+	),
+	TP_fast_assign(
+		NFSD_TRACE_PROC_CALL_ASSIGNMENTS(rqstp);
+		__entry->fh_hash = knfsd_fh_hash(&fhp->fh_handle);
+		__entry->gtime_tv_sec = guardtime ? guardtime->tv_sec : 0;
+		__entry->gtime_tv_nsec = guardtime ? guardtime->tv_nsec : 0;
+		__entry->ia_valid = iap->ia_valid;
+		__entry->ia_size = iap->ia_size;
+		__entry->ia_uid = __kuid_val(iap->ia_uid);
+		__entry->ia_gid = __kgid_val(iap->ia_gid);
+		__entry->ia_mode = iap->ia_mode;
+	),
+	TP_printk(
+		"xid=0x%08x fh_hash=0x%08x ia_valid=%s ia_size=%llu ia_mode=0%o ia_uid=%u ia_gid=%u guard_time=%lld.%u",
+		__entry->xid, __entry->fh_hash, show_ia_valid_flags(__entry->ia_valid),
+		__entry->ia_size, __entry->ia_mode, __entry->ia_uid, __entry->ia_gid,
+		__entry->gtime_tv_sec, __entry->gtime_tv_nsec
+	)
+)
 
 #endif /* _NFSD_TRACE_H */
 

fs/nfsd/vfs.c

···
 	bool		size_change = (iap->ia_valid & ATTR_SIZE);
 	int		retries;
 
+	trace_nfsd_vfs_setattr(rqstp, fhp, iap, guardtime);
+
 	if (iap->ia_valid & ATTR_SIZE) {
 		accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
 		ftype = S_IFREG;

include/trace/misc/fs.h

···
 		{ LOOKUP_BENEATH,	"BENEATH" }, \
 		{ LOOKUP_IN_ROOT,	"IN_ROOT" }, \
 		{ LOOKUP_CACHED,	"CACHED" })
+
+#define show_ia_valid_flags(flags)			\
+	__print_flags(flags, "|",			\
+		{ ATTR_MODE,		"MODE" },	\
+		{ ATTR_UID,		"UID" },	\
+		{ ATTR_GID,		"GID" },	\
+		{ ATTR_SIZE,		"SIZE" },	\
+		{ ATTR_ATIME,		"ATIME" },	\
+		{ ATTR_MTIME,		"MTIME" },	\
+		{ ATTR_CTIME,		"CTIME" },	\
+		{ ATTR_ATIME_SET,	"ATIME_SET" },	\
+		{ ATTR_MTIME_SET,	"MTIME_SET" },	\
+		{ ATTR_FORCE,		"FORCE" },	\
+		{ ATTR_KILL_SUID,	"KILL_SUID" },	\
+		{ ATTR_KILL_SGID,	"KILL_SGID" },	\
+		{ ATTR_FILE,		"FILE" },	\
+		{ ATTR_KILL_PRIV,	"KILL_PRIV" },	\
+		{ ATTR_OPEN,		"OPEN" },	\
+		{ ATTR_TIMES_SET,	"TIMES_SET" },	\
+		{ ATTR_TOUCH,		"TOUCH"},	\
+		{ ATTR_DELEG,		"DELEG"})