--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/usr/src/uts/common/fs/nfs/nfs_log.c	Tue Jun 14 00:00:00 2005 -0700
@@ -0,0 +1,1912 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/cred.h>
+#include <sys/cmn_err.h>
+#include <sys/debug.h>
+#include <sys/systm.h>
+#include <sys/kmem.h>
+#include <sys/disp.h>
+#include <sys/atomic.h>
+#include <rpc/types.h>
+#include <nfs/nfs.h>
+#include <nfs/nfssys.h>
+#include <nfs/export.h>
+#include <nfs/rnode.h>
+#include <rpc/auth.h>
+#include <rpc/svc.h>
+#include <rpc/xdr.h>
+#include <rpc/clnt.h>
+#include <nfs/nfs_log.h>
+
+#define	NUM_RECORDS_TO_WRITE 256
+#define	NUM_BYTES_TO_WRITE 65536
+
+extern krwlock_t exported_lock;
+
+static int nfslog_num_records_to_write = NUM_RECORDS_TO_WRITE;
+static int nfslog_num_bytes_to_write = NUM_BYTES_TO_WRITE;
+
+/*
+ * This struct is used to 'hide' the details of managing the log
+ * records internally to the logging code.  Allocation routines
+ * are used to obtain pieces of memory for XDR encoding.  This struct
+ * is a 'header' to those areas and a opaque cookie is used to pass
+ * this data structure between the allocating function and the put
+ * function.
+ */
+struct lr_alloc {
+	struct lr_alloc		*next;		/* links for write queuing */
+	struct lr_alloc		*prev;
+#define	LR_ALLOC_NOFREE	0x1			/* not present, call free */
+	int			lr_flags;
+	caddr_t			log_record;	/* address to XDR encoding */
+	size_t			size;		/* final size of encoding */
+	struct kmem_cache	*alloc_cache;	/* keep track of cache ptr */
+	struct exportinfo	*exi;		/* who are we related to? */
+	struct log_buffer	*lb;
+};
+
+struct flush_thread_params {
+	struct nfsl_flush_args tp_args;
+	int tp_error;
+};
+
+static int log_file_create(caddr_t, struct log_file **);
+static void log_file_rele(struct log_file *);
+static struct log_buffer *log_buffer_create(caddr_t);
+static void log_buffer_rele(struct log_buffer *);
+static int nfslog_record_append2all(struct lr_alloc *);
+static int nfslog_logbuffer_rename(struct log_buffer *);
+static void nfslog_logfile_wait(struct log_file *);
+static int nfslog_logfile_rename(char *, char *);
+static void nfslog_do_flush(struct flush_thread_params *);
+static void create_buffer_header(caddr_t *, size_t *, size_t *);
+
+static int nfslog_write_logrecords(struct log_file *, struct lr_alloc *, int);
+static void nfslog_free_logrecords(struct lr_alloc *);
+static int nfslog_records_flush_to_disk(struct log_buffer *);
+static int nfslog_records_flush_to_disk_nolock(struct log_buffer *);
+
+/*
+ * Read/Write lock that protects 'nfslog_buffer_list'.
+ * This lock must be held when searching or modifying 'nfslog_buffer_list'.
+ */
+static krwlock_t nfslog_buffer_list_lock;
+
+/*
+ * The list of "log_buffer" structures.
+ */
+struct log_buffer *nfslog_buffer_list = NULL;
+
+
+#define	LOG_BUFFER_HOLD(lbp)	{ \
+	mutex_enter(&(lbp)->lb_lock); \
+	(lbp)->lb_refcnt++; \
+	mutex_exit(&(lbp)->lb_lock); \
+}
+
+#define	LOG_FILE_HOLD(lfp)	{ \
+	mutex_enter(&(lfp)->lf_lock); \
+	(lfp)->lf_refcnt++; \
+	mutex_exit(&(lfp)->lf_lock); \
+}
+
+#define	LOG_FILE_RELE(lfp)	{ \
+	log_file_rele(lfp); \
+}
+
+/*
+ * These two macros are used to prep a logfile data structure and
+ * associated file for writing data.  Note that the lf_lock is
+ * held as a result of the call to the first macro.  This is used
+ * for serialization correctness between the logbuffer struct and
+ * the logfile struct.
+ */
+#define	LOG_FILE_LOCK_TO_WRITE(lfp)	{ \
+	mutex_enter(&(lfp)->lf_lock); \
+	(lfp)->lf_refcnt++; \
+	(lfp)->lf_writers++; \
+}
+
+#define	LOG_FILE_UNLOCK_FROM_WRITE(lfp)	{ \
+	(lfp)->lf_writers--; \
+	if ((lfp)->lf_writers == 0 && ((lfp)->lf_flags & L_WAITING)) { \
+		(lfp)->lf_flags &= ~L_WAITING; \
+		cv_broadcast(&(lfp)->lf_cv_waiters); \
+	} \
+	mutex_exit(&(lfp)->lf_lock); \
+	log_file_rele(lfp); \
+}
+
+int rfsl_log_buffer = 0;
+static int rfsl_log_file = 0;
+
+/* This array is used for memory allocation of record encoding spaces */
+static struct {
+	int	size;
+	struct kmem_cache *mem_cache;
+	char	*cache_name;
+} nfslog_mem_alloc[] = {
+#define	SMALL_INDX 0
+	{ NFSLOG_SMALL_RECORD_SIZE - sizeof (struct lr_alloc),
+	NULL, NFSLOG_SMALL_REC_NAME },
+#define	MEDIUM_INDX 1
+	{ NFSLOG_MEDIUM_RECORD_SIZE - sizeof (struct lr_alloc),
+	NULL, NFSLOG_MEDIUM_REC_NAME },
+#define	LARGE_INDX 2
+	{ NFSLOG_LARGE_RECORD_SIZE - sizeof (struct lr_alloc),
+	NULL, NFSLOG_LARGE_REC_NAME },
+	{ (-1), NULL }
+};
+
+/* Used to calculate the 'real' allocation size */
+#define	ALLOC_SIZE(index) \
+	(nfslog_mem_alloc[index].size + sizeof (struct lr_alloc))
+
+/*
+ * Initialize logging data buffer cache
+ */
+void
+nfslog_init()
+{
+	int indx;
+
+	rw_init(&nfslog_buffer_list_lock, NULL, RW_DEFAULT, NULL);
+
+	/*
+	 * Initialize the kmem caches for encoding
+	 */
+	for (indx = 0; nfslog_mem_alloc[indx].size != (-1); indx++) {
+		nfslog_mem_alloc[indx].mem_cache =
+			kmem_cache_create(nfslog_mem_alloc[indx].cache_name,
+				ALLOC_SIZE(indx),
+				0, NULL, NULL, NULL, NULL, NULL, 0);
+	}
+}
+
+/*
+ * Sets up the necessary log file and related buffers to enable logging
+ * on the given export point.
+ * Returns 0 on success, non-zero on failure.
+ */
+int
+nfslog_setup(struct exportinfo *exi)
+{
+	struct exportdata *kex;
+	struct log_buffer *lbp;
+	struct log_buffer *nlbp;
+
+	kex = &exi->exi_export;
+	ASSERT(kex->ex_flags & EX_LOG);
+
+	/*
+	 * Logging is enabled for the new export point, check
+	 * the existing log_buffer structures to see if the
+	 * desired buffer has already been opened. If so, point
+	 * the new exportinfo's exi_logbuffer to the existing
+	 * one.
+	 */
+	rw_enter(&nfslog_buffer_list_lock, RW_READER);
+	for (lbp = nfslog_buffer_list; lbp != NULL; lbp = lbp->lb_next) {
+		LOGGING_DPRINT((10,
+		    "searching for buffer... found log_buffer '%s'\n",
+				lbp->lb_path));
+		if (strcmp(lbp->lb_path, kex->ex_log_buffer) == 0) {
+			/* Found our match. Ref it and return */
+			LOG_BUFFER_HOLD(lbp);
+			exi->exi_logbuffer = lbp;
+			LOGGING_DPRINT((10,  "\tfound log_buffer for '%s'\n",
+				kex->ex_log_buffer));
+			rw_exit(&nfslog_buffer_list_lock);
+			return (0);
+		}
+	}
+	rw_exit(&nfslog_buffer_list_lock);
+
+	/*
+	 * New buffer needed, allocate it.
+	 * The buffer list lock has been dropped so we will need to search
+	 * the list again to ensure that another thread has not added
+	 * a matching buffer.
+	 */
+	if ((nlbp = log_buffer_create(kex->ex_log_buffer)) == NULL) {
+		/*
+		 * Failed the buffer creation for some reason so we
+		 * will need to return.
+		 */
+		return (EIO);
+	}
+
+	rw_enter(&nfslog_buffer_list_lock, RW_WRITER);
+	for (lbp = nfslog_buffer_list; lbp != NULL;
+		lbp = lbp->lb_next) {
+		if (strcmp(lbp->lb_path, kex->ex_log_buffer) == 0) {
+				/*
+				 * A log_buffer already exists for the
+				 * indicated buffer, use it instead.
+				 */
+			LOG_BUFFER_HOLD(lbp);
+
+			exi->exi_logbuffer = lbp;
+
+			LOGGING_DPRINT((10,
+				"found log_buffer for '%s' "
+				"after allocation\n",
+				kex->ex_log_buffer));
+
+			rw_exit(&nfslog_buffer_list_lock);
+
+			log_buffer_rele(nlbp);
+
+			return (0);
+		}
+	}
+	/*
+	 * Didn't find an existing log_buffer for this buffer,
+	 * use the the newly created one, and add to list.  We
+	 * increment the reference count because the node is
+	 * entered into the global list.
+	 */
+	LOGGING_DPRINT((10, "exportfs: adding nlbp=%p to list\n",
+		nlbp));
+
+	nlbp->lb_next = nfslog_buffer_list;
+	nfslog_buffer_list = nlbp;
+
+	LOG_BUFFER_HOLD(nlbp);	/* hold is for export entry */
+	exi->exi_logbuffer = nlbp;
+
+	rw_exit(&nfslog_buffer_list_lock);
+
+	return (0);
+}
+
+/*
+ * Disables logging for the given export point.
+ */
+void
+nfslog_disable(struct exportinfo *exi)
+{
+	log_buffer_rele(exi->exi_logbuffer);
+}
+
+/*
+ * Creates the corresponding log_buffer and log_file structures
+ * for the the buffer named 'name'.
+ * Returns a pointer to the log_buffer structure with reference one.
+ */
+static struct log_buffer *
+log_buffer_create(caddr_t name)
+{
+	struct log_buffer *buffer;
+	struct log_file *logfile;
+	int namelen = strlen(name);
+
+	LOGGING_DPRINT((10,  "log_buffer_create: %s\n", name));
+	if (log_file_create(name, &logfile))
+		return (NULL);
+
+	buffer = (struct log_buffer *)kmem_alloc(sizeof (*buffer), KM_SLEEP);
+	buffer->lb_refcnt = 1;
+	buffer->lb_rec_id = 0;
+	buffer->lb_path = (caddr_t)kmem_alloc(namelen + 1, KM_SLEEP);
+	bcopy(name, buffer->lb_path, namelen + 1);
+	buffer->lb_logfile = logfile;
+	buffer->lb_records = NULL;
+	buffer->lb_num_recs = 0;
+	buffer->lb_size_queued = 0;
+	mutex_init(&buffer->lb_lock, NULL, MUTEX_DEFAULT, NULL);
+	rfsl_log_buffer++;
+
+	return (buffer);
+}
+
+/*
+ * Release a log_buffer structure
+ */
+static void
+log_buffer_rele(struct log_buffer *lbp)
+{
+	int len;
+
+	mutex_enter(&lbp->lb_lock);
+	if (--lbp->lb_refcnt > 1) {
+		mutex_exit(&lbp->lb_lock);
+		return;
+	}
+
+	if (lbp->lb_refcnt < 0) {
+		panic("log_rele: log_buffer refcnt < 0");
+		/*NOTREACHED*/
+	}
+
+	/*
+	 * Need to drop the lb_lock before acquiring the
+	 * nfslog_buffer_list_lock. To avoid double free we need
+	 * to hold an additional reference to the log buffer.
+	 * This will ensure that no two threads will simultaneously
+	 * be trying to free the same log buffer.
+	 */
+
+	if (lbp->lb_refcnt == 1) {
+
+		/*
+		 * If the ref count is 1, then the last
+		 * unshare/reference has been given up and we need to
+		 * clean up the buffer and remove it from the buffer
+		 * list.
+		 */
+		LOGGING_DPRINT((10,
+			"log_buffer_rele lbp=%p disconnecting\n", lbp));
+		/*
+		 * Hold additional reference before dropping the lb_lock
+		 */
+
+		lbp->lb_refcnt++;
+		mutex_exit(&lbp->lb_lock);
+
+		/*
+		 * Make sure that all of the buffered records are written.
+		 * Don't bother checking the write return value since there
+		 * isn't much we can do at this point.
+		 */
+		(void) nfslog_records_flush_to_disk(lbp);
+
+		rw_enter(&nfslog_buffer_list_lock, RW_WRITER);
+		mutex_enter(&lbp->lb_lock);
+		/*
+		 * Drop the reference count held above.
+		 * If the ref count is still > 1 then someone has
+		 * stepped in to use this log buffer.  unlock and return.
+		 */
+		if (--lbp->lb_refcnt > 1) {
+			mutex_exit(&lbp->lb_lock);
+			rw_exit(&nfslog_buffer_list_lock);
+			return;
+		}
+
+		if (lbp == nfslog_buffer_list) {
+			nfslog_buffer_list = lbp->lb_next;
+		} else {
+			struct log_buffer *tlbp;
+
+			/* Drop the log_buffer from the master list */
+			for (tlbp = nfslog_buffer_list; tlbp->lb_next != NULL;
+					tlbp = tlbp->lb_next) {
+				if (tlbp->lb_next == lbp) {
+					tlbp->lb_next = lbp->lb_next;
+					break;
+				}
+			}
+		}
+
+		mutex_exit(&lbp->lb_lock);
+		rw_exit(&nfslog_buffer_list_lock);
+	}
+	/*
+	 * ref count zero; finish clean up.
+	 */
+	LOGGING_DPRINT((10, "log_buffer_rele lbp=%p freeing\n", lbp));
+
+	log_file_rele(lbp->lb_logfile);
+	len = strlen(lbp->lb_path) + 1;
+	kmem_free(lbp->lb_path, len);
+	kmem_free(lbp, sizeof (*lbp));
+	rfsl_log_buffer--;
+}
+
+/*
+ * Creates the corresponding log_file structure for the buffer
+ * named 'log_file_name'.
+ * 'log_file_name' is created by concatenating 'origname' and LOG_INPROG_STRING.
+ * 'logfile' is set to be the log_file structure with reference one.
+ */
+static int
+log_file_create(caddr_t origname, struct log_file **lfpp)
+{
+	vnode_t *vp = NULL;
+	char *name;
+	int namelen;
+	int error;
+	struct log_file *logfile = NULL;
+	vattr_t va;
+	caddr_t loghdr = NULL;
+	size_t loghdr_len = 0;
+	size_t loghdr_free = 0;
+
+	namelen = strlen(origname) + strlen(LOG_INPROG_STRING);
+	name = (caddr_t)kmem_alloc(namelen + 1, KM_SLEEP);
+	(void) sprintf(name, "%s%s", origname, LOG_INPROG_STRING);
+
+	LOGGING_DPRINT((3, "log_file_create: %s\n", name));
+	if (error = vn_open(name, UIO_SYSSPACE, FCREAT|FWRITE|FOFFMAX,
+			LOG_MODE, &vp, CRCREAT, 0)) {
+		nfs_cmn_err(error, CE_WARN,
+			"log_file_create: Can not open %s - error %m", name);
+		goto out;
+	}
+	LOGGING_DPRINT((3, "log_file_create: %s vp=%p v_count=%d\n",
+		name, vp, vp->v_count));
+
+	logfile = (struct log_file *)kmem_zalloc(sizeof (*logfile), KM_SLEEP);
+	logfile->lf_path = name;
+	/*
+	 * No need to bump the vnode reference count since it is set
+	 * to one by vn_open().
+	 */
+	logfile->lf_vp = vp;
+	logfile->lf_refcnt = 1;
+	mutex_init(&logfile->lf_lock, NULL, MUTEX_DEFAULT, NULL);
+	rfsl_log_file++;
+
+	va.va_mask = AT_SIZE;
+	error = VOP_GETATTR(vp, &va, 0, CRED());
+	if (error) {
+		nfs_cmn_err(error, CE_WARN,
+			"log_file_create: Can not stat %s - error = %m",
+			name);
+		goto out;
+	}
+
+	if (va.va_size == 0) {
+		struct lr_alloc lr;
+
+		/*
+		 * Write Header.
+		 */
+		create_buffer_header(&loghdr, &loghdr_len, &loghdr_free);
+		/*
+		 * Dummy up a lr_alloc struct for the write
+		 */
+		lr.next = lr.prev = &lr;
+		lr.lr_flags = 0;
+		lr.log_record = loghdr;
+		lr.size = loghdr_len;
+		lr.alloc_cache = NULL;
+		lr.exi = NULL;
+		lr.lb = NULL;
+
+		mutex_enter(&logfile->lf_lock);
+
+		error = nfslog_write_logrecords(logfile, &lr, 1);
+
+		mutex_exit(&logfile->lf_lock);
+
+		if (error != 0) {
+			nfs_cmn_err(error, CE_WARN,
+				"log_file_create: Can not write header "
+				"on %s - error = %m", name);
+			goto out;
+		}
+	}
+	*lfpp = logfile;
+
+	if (loghdr != NULL)
+		kmem_free(loghdr, loghdr_free);
+
+	return (0);
+
+out:
+	if (vp != NULL) {
+		int error1;
+		error1 = VOP_CLOSE(vp, FCREAT|FWRITE|FOFFMAX, 1, (offset_t)0,
+				CRED());
+		if (error1) {
+			nfs_cmn_err(error1, CE_WARN,
+				"log_file_create: Can not close %s - "
+				"error = %m", name);
+		}
+		VN_RELE(vp);
+	}
+
+	kmem_free(name, namelen + 1);
+	if (logfile != NULL) {
+		mutex_destroy(&logfile->lf_lock);
+		kmem_free(logfile, sizeof (*logfile));
+		rfsl_log_file--;
+	}
+	if (loghdr != NULL)
+		kmem_free(loghdr, loghdr_free);
+
+	return (error);
+}
+
+/*
+ * Release a log_file structure
+ */
+static void
+log_file_rele(struct log_file *lfp)
+{
+	int len;
+	int error;
+
+	mutex_enter(&lfp->lf_lock);
+	if (--lfp->lf_refcnt > 0) {
+		LOGGING_DPRINT((10,
+			"log_file_rele lfp=%p decremented refcnt to %d\n",
+			lfp, lfp->lf_refcnt));
+		mutex_exit(&lfp->lf_lock);
+		return;
+	}
+	if (lfp->lf_refcnt < 0) {
+		panic("log_file_rele: log_file refcnt < 0");
+		/*NOTREACHED*/
+	}
+
+	LOGGING_DPRINT((10, "log_file_rele lfp=%p freeing node\n", lfp));
+
+	lfp->lf_flags &= ~(L_PRINTED | L_ERROR);
+
+	ASSERT(lfp->lf_flags == 0);
+	ASSERT(lfp->lf_writers == 0);
+
+	if (error = VOP_CLOSE(lfp->lf_vp, FCREAT|FWRITE|FOFFMAX, 1, (offset_t)0,
+		CRED())) {
+		nfs_cmn_err(error, CE_WARN,
+			"NFS: Could not close log buffer %s - error = %m",
+			lfp->lf_path);
+#ifdef DEBUG
+	} else {
+		LOGGING_DPRINT((3,
+			"log_file_rele: %s has been closed vp=%p "
+			"v_count=%d\n",
+			lfp->lf_path, lfp->lf_vp, lfp->lf_vp->v_count));
+#endif
+	}
+	VN_RELE(lfp->lf_vp);
+
+	len = strlen(lfp->lf_path) + 1;
+	kmem_free(lfp->lf_path, len);
+	kmem_free(lfp, sizeof (*lfp));
+	rfsl_log_file--;
+}
+
+/*
+ * Allocates a record of the size specified.
+ * 'exi' identifies the exportinfo structure being logged.
+ * 'size' indicates how much memory should be allocated
+ * 'cookie' is used to store an opaque value for the caller for later use
+ * 'flags' currently ignored.
+ *
+ * Returns a pointer to the beginning of the allocated memory.
+ * 'cookie' is a pointer to the 'lr_alloc' struct; this will be used
+ * to keep track of the encoded record and contains all the info
+ * for enqueuing the record on the log buffer for later writing.
+ *
+ * nfslog_record_put() must be used to 'free' this record or allocation.
+ */
+/* ARGSUSED */
+void *
+nfslog_record_alloc(
+	struct exportinfo *exi,
+	int alloc_indx,
+	void **cookie,
+	int flags)
+{
+	struct lr_alloc *lrp;
+
+	lrp = (struct lr_alloc *)
+		kmem_cache_alloc(nfslog_mem_alloc[alloc_indx].mem_cache,
+			KM_NOSLEEP);
+
+	if (lrp == NULL) {
+		*cookie = NULL;
+		return (NULL);
+	}
+
+	lrp->next = lrp;
+	lrp->prev = lrp;
+	lrp->lr_flags = 0;
+
+	lrp->log_record = (caddr_t)((uintptr_t)lrp +
+		(uintptr_t)sizeof (struct lr_alloc));
+	lrp->size = nfslog_mem_alloc[alloc_indx].size;
+	lrp->alloc_cache = nfslog_mem_alloc[alloc_indx].mem_cache;
+	lrp->exi = exi;
+
+	if (exi->exi_export.ex_flags & EX_LOG) {
+		LOG_BUFFER_HOLD(exi->exi_logbuffer);
+		lrp->lb = exi->exi_logbuffer;
+	} else {
+		lrp->lb = NULL;
+	}
+
+	*cookie = (void *)lrp;
+
+	LOGGING_DPRINT((3,
+		"nfslog_record_alloc(log_buffer=%p mem=%p size=%lu)\n",
+		exi->exi_logbuffer, lrp->log_record, lrp->size));
+	return (lrp->log_record);
+}
+
+/*
+ * After the above nfslog_record_alloc() has been called and a record
+ * encoded into the buffer that was returned, this function is called
+ * to handle appropriate disposition of the newly created record.
+ * The cookie value is the one that was returned from nfslog_record_alloc().
+ * Size is the actual size of the record that was encoded.  This is
+ * passed in because the size used for the alloc was just an approximation.
+ * The sync parameter is used to tell us if we need to force this record
+ * to disk and if not it will be queued for later writing.
+ *
+ * Note that if the size parameter has a value of 0, then the record is
+ * not written to the log and the associated data structures are released.
+ */
+void
+nfslog_record_put(void *cookie, size_t size, bool_t sync,
+	unsigned int which_buffers)
+{
+	struct lr_alloc *lrp = (struct lr_alloc *)cookie;
+	struct log_buffer *lbp = lrp->lb;
+
+	/*
+	 * If the caller has nothing to write or if there is
+	 * an apparent error, rele the buffer and free.
+	 */
+	if (size == 0 || size > lrp->size) {
+		nfslog_free_logrecords(lrp);
+		return;
+	}
+
+	/*
+	 * Reset the size to what actually needs to be written
+	 * This is used later on when the iovec is built for
+	 * writing the records to the log file.
+	 */
+	lrp->size = size;
+
+	/* append to all if public exi */
+	if (which_buffers == NFSLOG_ALL_BUFFERS) {
+		(void) nfslog_record_append2all(lrp);
+		nfslog_free_logrecords(lrp);
+		return;
+	}
+
+	/* Insert the record on the list to be written */
+	mutex_enter(&lbp->lb_lock);
+	if (lbp->lb_records == NULL) {
+		lbp->lb_records = (caddr_t)lrp;
+		lbp->lb_num_recs = 1;
+		lbp->lb_size_queued = lrp->size;
+	} else {
+		insque(lrp, ((struct lr_alloc *)lbp->lb_records)->prev);
+		lbp->lb_num_recs++;
+		lbp->lb_size_queued += lrp->size;
+	}
+
+	/*
+	 * Determine if the queue for this log buffer should be flushed.
+	 * This is done by either the number of records queued, the total
+	 * size of all records queued or by the request of the caller
+	 * via the sync parameter.
+	 */
+	if (lbp->lb_size_queued >= nfslog_num_bytes_to_write ||
+		lbp->lb_num_recs > nfslog_num_records_to_write ||
+		sync == TRUE) {
+		mutex_exit(&lbp->lb_lock);
+		(void) nfslog_records_flush_to_disk(lbp);
+	} else {
+		mutex_exit(&lbp->lb_lock);
+	}
+
+}
+
+/*
+ * Examine the log_buffer struct to see if there are queue log records
+ * that need to be written to disk.  If some exist, pull them off of
+ * the log buffer and write them to the log file.
+ */
+static int
+nfslog_records_flush_to_disk(struct log_buffer *lbp)
+{
+
+	mutex_enter(&lbp->lb_lock);
+
+	if (lbp->lb_records == NULL) {
+		mutex_exit(&lbp->lb_lock);
+		return (0);
+	}
+	return	(nfslog_records_flush_to_disk_nolock(lbp));
+}
+
+/*
+ * Function requires that the caller holds lb_lock.
+ * Function flushes any records in the log buffer to the disk.
+ * Function drops the lb_lock on return.
+ */
+
+static int
+nfslog_records_flush_to_disk_nolock(struct log_buffer *lbp)
+{
+	struct log_file *lfp = NULL;
+	struct lr_alloc *lrp_writers;
+	int num_recs;
+	int error = 0;
+
+	ASSERT(MUTEX_HELD(&lbp->lb_lock));
+
+	lfp = lbp->lb_logfile;
+
+	LOG_FILE_LOCK_TO_WRITE(lfp);
+	ASSERT(lbp->lb_records != NULL);
+
+	lrp_writers = (struct lr_alloc *)lbp->lb_records;
+	lbp->lb_records = NULL;
+	num_recs = lbp->lb_num_recs;
+	lbp->lb_num_recs = 0;
+	lbp->lb_size_queued = 0;
+	mutex_exit(&lbp->lb_lock);
+	error = nfslog_write_logrecords(lfp, lrp_writers, num_recs);
+
+	LOG_FILE_UNLOCK_FROM_WRITE(lfp);
+
+	nfslog_free_logrecords(lrp_writers);
+	return (error);
+}
+
+
+/*
+ * Take care of writing the provided log record(s) to the log file.
+ * We group the log records with an iovec and use VOP_WRITE to append
+ * them to the end of the log file.
+ */
+static int
+nfslog_write_logrecords(struct log_file *lfp,
+	struct lr_alloc *lrp_writers, int num_recs)
+{
+	struct uio uio;
+	struct iovec *iovp;
+	int size_iovecs;
+	vnode_t *vp;
+	struct vattr va;
+	struct lr_alloc *lrp;
+	int i;
+	ssize_t len;
+	int ioflag = FAPPEND;
+	int error = 0;
+
+	ASSERT(MUTEX_HELD(&lfp->lf_lock));
+
+	vp = lfp->lf_vp;
+
+	size_iovecs = sizeof (struct iovec) * num_recs;
+	iovp = (struct iovec *)kmem_alloc(size_iovecs, KM_NOSLEEP);
+
+	if (iovp == NULL) {
+		error = ENOMEM;
+		goto out;
+	}
+
+	/* Build the iovec based on the list of log records */
+	i = 0;
+	len = 0;
+	lrp = lrp_writers;
+	do {
+		iovp[i].iov_base = lrp->log_record;
+		iovp[i].iov_len = lrp->size;
+		len += lrp->size;
+		lrp = lrp->next;
+		i++;
+	} while (lrp != lrp_writers);
+
+	ASSERT(i == num_recs);
+
+	uio.uio_iov = iovp;
+	uio.uio_iovcnt = num_recs;
+	uio.uio_loffset = 0;
+	uio.uio_segflg = (short)UIO_SYSSPACE;
+	uio.uio_resid = len;
+	uio.uio_llimit = (rlim64_t)MAXOFFSET_T;
+	uio.uio_fmode = FWRITE;
+	uio.uio_extflg = UIO_COPY_DEFAULT;
+
+	/*
+	 * Save the size. If the write fails, reset the size to avoid
+	 * corrupted log buffer files.
+	 */
+	va.va_mask = AT_SIZE;
+
+	(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);  /* UIO_WRITE */
+	if ((error = VOP_GETATTR(vp, &va, 0, CRED())) == 0) {
+		if ((len + va.va_size) < (MAXOFF32_T)) {
+			error = VOP_WRITE(vp, &uio, ioflag, CRED(), NULL);
+			if (uio.uio_resid)
+				error = ENOSPC;
+			if (error)
+				(void) VOP_SETATTR(vp, &va, 0, CRED(), NULL);
+		} else {
+			if (!(lfp->lf_flags & L_PRINTED)) {
+				cmn_err(CE_WARN,
+				    "NFS Logging: buffer file %s exceeds 2GB; "
+				    "stopped writing buffer \n", lfp->lf_path);
+			}
+			error = ENOSPC;
+		}
+	}
+	VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
+
+	kmem_free(iovp, size_iovecs);
+
+out:
+	if (error) {
+		if (!(lfp->lf_flags & L_PRINTED)) {
+			nfs_cmn_err(error, CE_WARN,
+				"NFS Logging disabled for buffer %s - "
+				"write error = %m\n", lfp->lf_path);
+			lfp->lf_flags |= L_PRINTED;
+		}
+	} else if (lfp->lf_flags & (L_ERROR | L_PRINTED)) {
+		lfp->lf_flags &= ~(L_ERROR | L_PRINTED);
+		cmn_err(CE_WARN,
+			"NFS Logging re-enabled for buffer %s\n", lfp->lf_path);
+	}
+
+	return (error);
+}
+
+static void
+nfslog_free_logrecords(struct lr_alloc *lrp_writers)
+{
+	struct lr_alloc *lrp = lrp_writers;
+	struct lr_alloc *lrp_free;
+
+	do {
+		lrp_free = lrp;
+
+		lrp = lrp->next;
+
+		/*
+		 * Check to see if we are supposed to free this structure
+		 * and relese the log_buffer ref count.
+		 * It may be the case that the caller does not want this
+		 * structure and its record contents freed just yet.
+		 */
+		if ((lrp_free->lr_flags & LR_ALLOC_NOFREE) == 0) {
+			if (lrp_free->lb != NULL)
+				log_buffer_rele(lrp_free->lb);
+			if (lrp_free->alloc_cache) /* double check */
+				kmem_cache_free(lrp_free->alloc_cache,
+					(void *)lrp_free);
+		} else {
+			/*
+			 * after being pulled from the list the
+			 * pointers need to be reinitialized.
+			 */
+			lrp_free->next = lrp_free;
+			lrp_free->prev = lrp_free;
+		}
+
+	} while (lrp != lrp_writers);
+}
+
+/*
+ * Rename lbp->lb_logfile to reflect the true name requested by 'share'
+ */
+static int
+nfslog_logbuffer_rename(struct log_buffer *lbp)
+{
+	struct log_file *lf;
+	int error;
+	struct log_file *logfile;
+
+	/*
+	 * Try our best to get the cache records into the log file
+	 * before the rename occurs.
+	 */
+	(void) nfslog_records_flush_to_disk(lbp);
+
+	/*
+	 * Hold lb_lock before retrieving
+	 * lb_logfile.
+	 * Hold a reference to the
+	 * "lf" structure. this is
+	 * same as LOG_FILE_HOLD()
+	 */
+	mutex_enter(&(lbp)->lb_lock);
+	lf = lbp->lb_logfile;
+	mutex_enter(&(lf)->lf_lock);
+	mutex_exit(&(lbp)->lb_lock);
+	lf->lf_refcnt++;
+	mutex_exit(&(lf)->lf_lock);
+
+	LOGGING_DPRINT((10, "nfslog_logbuffer_rename: renaming %s to %s\n",
+		lf->lf_path, lbp->lb_path));
+
+	/*
+	 * rename the current buffer to what the daemon expects
+	 */
+	if (error = nfslog_logfile_rename(lf->lf_path, lbp->lb_path))
+		goto out;
+
+	/*
+	 * Create a new working buffer file and have all new data sent there.
+	 */
+	if (error = log_file_create(lbp->lb_path, &logfile)) {
+		/* Attempt to rename to original */
+		(void) nfslog_logfile_rename(lbp->lb_path, lf->lf_path);
+		goto out;
+	}
+
+	/*
+	 * Hold the lb_lock here, this will make
+	 * all the threads trying to access lb->logfile block
+	 * and get a new logfile structure instead of old one.
+	 */
+	mutex_enter(&(lbp)->lb_lock);
+	lbp->lb_logfile = logfile;
+	mutex_exit(&(lbp)->lb_lock);
+
+	LOG_FILE_RELE(lf);	/* release log_buffer's reference */
+
+	/*
+	 * Wait for log_file to be in a quiescent state before we
+	 * return to our caller to let it proceed with the reading of
+	 * this file.
+	 */
+	nfslog_logfile_wait(lf);
+
+out:
+	/*
+	 * Release our reference on "lf" in two different cases.
+	 * 1. Error condition, release only the reference
+	 *    that we held at the begining of this
+	 *    routine on "lf" structure.
+	 * 2. Fall through condition, no errors but the old
+	 *    logfile structure "lf" has been replaced with
+	 *    the new "logfile" structure, so release the
+	 *    reference that was part of the creation of
+	 *    "lf" structure to free up the resources.
+	 */
+
+	LOG_FILE_RELE(lf);
+
+	return (error);
+}
+
+/*
+ * Renames the 'from' file to 'new'.
+ */
+static int
+nfslog_logfile_rename(char *from, char *new)
+{
+	int error;
+
+	if (error = vn_rename(from, new, UIO_SYSSPACE)) {
+		cmn_err(CE_WARN,
+			"nfslog_logfile_rename: couldn't rename %s to %s\n",
+			from, new);
+	}
+	return (error);
+}
+
+/*
+ * Wait for the log_file writers to finish before returning
+ */
+static void
+nfslog_logfile_wait(struct log_file *lf)
+{
+	mutex_enter(&lf->lf_lock);
+	while (lf->lf_writers > 0) {
+		lf->lf_flags |= L_WAITING;
+		(void) cv_wait_sig(&lf->lf_cv_waiters, &lf->lf_lock);
+	}
+	mutex_exit(&lf->lf_lock);
+}
+
+static int
+nfslog_record_append2all(struct lr_alloc *lrp)
+{
+	struct log_buffer *lbp, *nlbp;
+	int error, ret_error = 0;
+	int lr_flags = lrp->lr_flags;
+
+	rw_enter(&nfslog_buffer_list_lock, RW_READER);
+	if ((lbp = nfslog_buffer_list) != NULL)
+		LOG_BUFFER_HOLD(lbp);
+	for (nlbp = NULL; lbp != NULL; lbp = nlbp) {
+		if ((nlbp = lbp->lb_next) != NULL) {
+			/*
+			 * Remember next element in the list
+			 */
+			LOG_BUFFER_HOLD(nlbp);
+		}
+		rw_exit(&nfslog_buffer_list_lock);
+
+		/*
+		 * Insert the record on the buffer's list to be written
+		 * and then flush the records to the log file.
+		 * Make sure to set the no free flag so that the
+		 * record can be used for the next write
+		 */
+		lrp->lr_flags = LR_ALLOC_NOFREE;
+
+		ASSERT(lbp != NULL);
+		mutex_enter(&lbp->lb_lock);
+		if (lbp->lb_records == NULL) {
+			lbp->lb_records = (caddr_t)lrp;
+			lbp->lb_num_recs = 1;
+			lbp->lb_size_queued = lrp->size;
+		} else {
+			insque(lrp, ((struct lr_alloc *)lbp->lb_records)->prev);
+			lbp->lb_num_recs++;
+			lbp->lb_size_queued += lrp->size;
+		}
+
+		/*
+		 * Flush log records to disk.
+		 * Function is called with lb_lock held.
+		 * Function drops the lb_lock on return.
+		 */
+		error = nfslog_records_flush_to_disk_nolock(lbp);
+
+		if (error) {
+			ret_error = -1;
+			nfs_cmn_err(error, CE_WARN,
+				"rfsl_log_pubfh: could not append record to "
+				"\"%s\" error = %m\n", lbp->lb_path);
+		}
+		log_buffer_rele(lbp);
+		rw_enter(&nfslog_buffer_list_lock, RW_READER);
+	}
+	rw_exit(&nfslog_buffer_list_lock);
+
+	lrp->lr_flags = lr_flags;
+
+	return (ret_error);
+}
+
+#ifdef DEBUG
+static int logging_debug = 0;
+
+/*
+ * 0) no debugging
+ * 3) current test software
+ * 10) random stuff
+ */
+void
+nfslog_dprint(const int level, const char *fmt, ...)
+{
+	va_list args;
+
+	if (logging_debug == level ||
+	    (logging_debug > 10 && (logging_debug - 10) >= level)) {
+		va_start(args, fmt);
+		(void) vprintf(fmt, args);
+		va_end(args);
+	}
+}
+
+#endif /* DEBUG */
+
+/*
+ * NFS Log Flush system call
+ * Caller must check privileges.
+ */
+/* ARGSUSED */
+int
+nfsl_flush(struct nfsl_flush_args *args, model_t model)
+{
+	struct flush_thread_params *tparams;
+	struct nfsl_flush_args *nfsl_args;
+	int error = 0;
+	ulong_t buffer_len;
+	STRUCT_HANDLE(nfsl_flush_args, uap);
+
+	STRUCT_SET_HANDLE(uap, model, args);
+
+	tparams = (struct flush_thread_params *)
+		kmem_zalloc(sizeof (*tparams), KM_SLEEP);
+
+	nfsl_args = &tparams->tp_args;
+	nfsl_args->version =  STRUCT_FGET(uap, version);
+	if (nfsl_args->version != NFSL_FLUSH_ARGS_VERS) {
+		cmn_err(CE_WARN, "nfsl_flush: exected version %d, got %d",
+			NFSL_FLUSH_ARGS_VERS, nfsl_args->version);
+		return (EIO);
+	}
+
+	nfsl_args->directive = STRUCT_FGET(uap, directive);
+	if ((nfsl_args->directive & NFSL_ALL) == 0) {
+		/*
+		 * Process a specific buffer
+		 */
+		nfsl_args->buff_len = STRUCT_FGET(uap, buff_len);
+
+		nfsl_args->buff = (char *)
+			kmem_alloc(nfsl_args->buff_len, KM_NOSLEEP);
+		if (nfsl_args->buff == NULL)
+			return (ENOMEM);
+
+		error = copyinstr((const char *)STRUCT_FGETP(uap, buff),
+			nfsl_args->buff, nfsl_args->buff_len, &buffer_len);
+		if (error)
+			return (EFAULT);
+
+		if (nfsl_args->buff_len != buffer_len)
+			return (EFAULT);
+	}
+
+	LOGGING_DPRINT((10, "nfsl_flush: Flushing %s buffer(s)\n",
+		nfsl_args->directive & NFSL_ALL ? "all" : nfsl_args->buff));
+
+	if (nfsl_args->directive & NFSL_SYNC) {
+		/*
+		 * Do the work synchronously
+		 */
+		nfslog_do_flush(tparams);
+		error = tparams->tp_error;
+		kmem_free(nfsl_args->buff, nfsl_args->buff_len);
+		kmem_free(tparams, sizeof (*tparams));
+	} else {
+		/*
+		 * Do the work asynchronously
+		 */
+		(void) thread_create(NULL, 0, nfslog_do_flush,
+		    tparams, 0, &p0, TS_RUN, minclsyspri);
+	}
+
+	return (error);
+}
+
+/*
+ * This is where buffer flushing would occur, but there is no buffering
+ * at this time.
+ * Possibly rename the log buffer for processing.
+ * Sets tparams->ta_error equal to the value of the error that occured,
+ * 0 otherwise.
+ * Returns ENOENT if the buffer is not found.
+ */
+static void
+nfslog_do_flush(struct flush_thread_params *tparams)
+{
+	struct nfsl_flush_args *args;
+	struct log_buffer *lbp;
+	int error = ENOENT;
+	int found = 0;
+	char *buf_inprog;	/* name of buff in progress */
+	int buf_inprog_len;
+
+	/*
+	 * Sanity check on the arguments.
+	 */
+	if (!tparams)
+		return;
+	args = &tparams->tp_args;
+	if (!args)
+		return;
+
+	rw_enter(&nfslog_buffer_list_lock, RW_READER);
+	for (lbp = nfslog_buffer_list; lbp != NULL; lbp = lbp->lb_next) {
+		if (args->directive & NFSL_ALL) {
+			(void) nfslog_records_flush_to_disk(lbp);
+		} else {
+			if ((strcmp(lbp->lb_path, args->buff) == 0) &&
+				(args->directive & NFSL_RENAME)) {
+
+				error = nfslog_logbuffer_rename(lbp);
+				found++;
+				break;
+			}
+		}
+	}
+	rw_exit(&nfslog_buffer_list_lock);
+
+	if (!found && ((args->directive & NFSL_ALL) == 0) &&
+	    (args->directive & NFSL_RENAME)) {
+		/*
+		 * The specified buffer is not currently in use,
+		 * simply rename the file indicated.
+		 */
+		buf_inprog_len = strlen(args->buff) +
+			strlen(LOG_INPROG_STRING) + 1;
+		buf_inprog = (caddr_t)kmem_alloc(buf_inprog_len, KM_SLEEP);
+		(void) sprintf(buf_inprog, "%s%s",
+			args->buff, LOG_INPROG_STRING);
+
+		error = nfslog_logfile_rename(buf_inprog, args->buff);
+
+		kmem_free(buf_inprog, buf_inprog_len);
+	}
+
+out:
+	if ((args->directive & NFSL_SYNC) == 0) {
+		/*
+		 * Work was performed asynchronously, the caller is
+		 * no longer waiting for us.
+		 * Free the thread arguments and exit.
+		 */
+		kmem_free(args->buff, args->buff_len);
+		kmem_free(tparams, sizeof (*tparams));
+		thread_exit();
+		/* NOTREACHED */
+	}
+
+	tparams->tp_error = error;
+}
+
+/*
+ * Generate buffer_header.
+ * 'loghdr' points the the buffer_header, and *reclen
+ * contains the length of the buffer.
+ */
+static void
+create_buffer_header(caddr_t *loghdr, size_t *reclen, size_t *freesize)
+{
+	timestruc_t		now;
+	nfslog_buffer_header	lh;
+	XDR			xdrs;
+	unsigned int		final_size;
+
+
+	/* pick some size that will hold the buffer_header */
+	*freesize = NFSLOG_SMALL_RECORD_SIZE;
+
+	/*
+	 * Fill header
+	 */
+	lh.bh_length = 0;	/* don't know yet how large it will be */
+	lh.bh_version = NFSLOG_BUF_VERSION;
+	lh.bh_flags = 0;
+	lh.bh_offset = 0;
+	gethrestime(&now);
+	TIMESPEC_TO_TIMESPEC32(&lh.bh_timestamp, &now);
+
+	/*
+	 * Encode the header
+	 */
+	*loghdr = (caddr_t)kmem_alloc(*freesize, KM_SLEEP);
+	xdrmem_create(&xdrs, *loghdr, *freesize, XDR_ENCODE);
+
+	(void) xdr_nfslog_buffer_header(&xdrs, &lh);
+
+	/*
+	 * Reset with final size of the encoded data
+	 */
+	final_size = xdr_getpos(&xdrs);
+	xdr_setpos(&xdrs, 0);
+	(void) xdr_u_int(&xdrs, &final_size);
+
+	*reclen = (size_t)final_size;
+}
+
+/*
+ * ****************************************************************
+ * RPC dispatch table for logging
+ * Indexed by program, version, proc
+ * Based on NFS dispatch table.
+ */
+struct nfslog_proc_disp {
+	bool_t	(*xdrargs)();
+	bool_t	(*xdrres)();
+	bool_t	affects_transactions;	/* Operation affects transaction */
+					/* processing */
+};
+
+struct nfslog_vers_disp {
+	int	nfslog_dis_nprocs;			/* number of procs */
+	struct nfslog_proc_disp	*nfslog_dis_proc_table;	/* proc array */
+};
+
+struct nfslog_prog_disp {
+	int	nfslog_dis_prog;		/* program number */
+	int	nfslog_dis_versmin;		/* Minimum version value */
+	int	nfslog_dis_nvers;		/* Number of version values */
+	struct nfslog_vers_disp	*nfslog_dis_vers_table;	/* versions array */
+};
+
+static int rfs_log_bad = 0;	/* incremented on bad log attempts */
+static int rfs_log_good = 0;	/* incremented on successful log attempts */
+
+/*
+ * Define the actions taken per prog/vers/proc:
+ *
+ * In some cases, the nl types are the same as the nfs types and a simple
+ * bcopy should suffice. Rather that define tens of identical procedures,
+ * simply define these to bcopy. Similarly this takes care of different
+ * procs that use same parameter struct.
+ */
+
+static struct nfslog_proc_disp nfslog_proc_v2[] = {
+	/*
+	 * NFS VERSION 2
+	 */
+
+	/* RFS_NULL = 0 */
+	{xdr_void, xdr_void, FALSE},
+
+	/* RFS_GETATTR = 1 */
+	{xdr_fhandle, xdr_nfslog_getattrres, FALSE},
+
+	/* RFS_SETATTR = 2 */
+	{xdr_nfslog_setattrargs, xdr_nfsstat, TRUE},
+
+	/* RFS_ROOT = 3 *** NO LONGER SUPPORTED *** */
+	{xdr_void, xdr_void, FALSE},
+
+	/* RFS_LOOKUP = 4 */
+	{xdr_nfslog_diropargs, xdr_nfslog_diropres, TRUE},
+
+	/* RFS_READLINK = 5 */
+	{xdr_fhandle, xdr_nfslog_rdlnres, FALSE},
+
+	/* RFS_READ = 6 */
+	{xdr_nfslog_nfsreadargs, xdr_nfslog_rdresult, TRUE},
+
+	/* RFS_WRITECACHE = 7 *** NO LONGER SUPPORTED *** */
+	{xdr_void, xdr_void, FALSE},
+
+	/* RFS_WRITE = 8 */
+	{xdr_nfslog_writeargs, xdr_nfslog_writeresult, TRUE},
+
+	/* RFS_CREATE = 9 */
+	{xdr_nfslog_createargs, xdr_nfslog_diropres, TRUE},
+
+	/* RFS_REMOVE = 10 */
+	{xdr_nfslog_diropargs, xdr_nfsstat, TRUE},
+
+	/* RFS_RENAME = 11 */
+	{xdr_nfslog_rnmargs, xdr_nfsstat, TRUE},
+
+	/* RFS_LINK = 12 */
+	{xdr_nfslog_linkargs, xdr_nfsstat, TRUE},
+
+	/* RFS_SYMLINK = 13 */
+	{xdr_nfslog_symlinkargs, xdr_nfsstat, TRUE},
+
+	/* RFS_MKDIR = 14 */
+	{xdr_nfslog_createargs, xdr_nfslog_diropres, TRUE},
+
+	/* RFS_RMDIR = 15 */
+	{xdr_nfslog_diropargs, xdr_nfsstat, TRUE},
+
+	/* RFS_READDIR = 16 */
+	{xdr_nfslog_rddirargs, xdr_nfslog_rddirres, TRUE},
+
+	/* RFS_STATFS = 17 */
+	{xdr_fhandle, xdr_nfslog_statfs, FALSE},
+};
+
+
+/*
+ * NFS VERSION 3
+ */
+
+static struct nfslog_proc_disp nfslog_proc_v3[] = {
+
+	/* NFSPROC3_NULL = 0 */
+	{xdr_void, xdr_void, FALSE},
+
+	/* NFSPROC3_GETATTR = 1 */
+	{xdr_nfs_fh3, xdr_nfslog_GETATTR3res, FALSE},
+
+	/* NFSPROC3_SETATTR = 2 */
+	{xdr_nfslog_SETATTR3args, xdr_nfslog_SETATTR3res, TRUE},
+
+	/* NFSPROC3_LOOKUP = 3 */
+	{xdr_nfslog_diropargs3, xdr_nfslog_LOOKUP3res, TRUE},
+
+	/* NFSPROC3_ACCESS = 4 */
+	{xdr_nfslog_ACCESS3args, xdr_nfslog_ACCESS3res, FALSE},
+
+	/* NFSPROC3_READLINK = 5 */
+	{xdr_nfs_fh3, xdr_nfslog_READLINK3res, FALSE},
+
+	/* NFSPROC3_READ = 6 */
+	{xdr_nfslog_READ3args, xdr_nfslog_READ3res, TRUE},
+
+	/* NFSPROC3_WRITE = 7 */
+	{xdr_nfslog_WRITE3args, xdr_nfslog_WRITE3res, TRUE},
+
+	/* NFSPROC3_CREATE = 8 */
+	{xdr_nfslog_CREATE3args, xdr_nfslog_CREATE3res, TRUE},
+
+	/* NFSPROC3_MKDIR = 9 */
+	{xdr_nfslog_MKDIR3args, xdr_nfslog_MKDIR3res, TRUE},
+
+	/* NFSPROC3_SYMLINK = 10 */
+	{xdr_nfslog_SYMLINK3args, xdr_nfslog_SYMLINK3res, TRUE},
+
+	/* NFSPROC3_MKNOD = 11 */
+	{xdr_nfslog_MKNOD3args, xdr_nfslog_MKNOD3res, TRUE},
+
+	/* NFSPROC3_REMOVE = 12 */
+	{xdr_nfslog_REMOVE3args, xdr_nfslog_REMOVE3res, TRUE},
+
+	/* NFSPROC3_RMDIR = 13 */
+	{xdr_nfslog_RMDIR3args, xdr_nfslog_RMDIR3res, TRUE},
+
+	/* NFSPROC3_RENAME = 14 */
+	{xdr_nfslog_RENAME3args, xdr_nfslog_RENAME3res, TRUE},
+
+	/* NFSPROC3_LINK = 15 */
+	{xdr_nfslog_LINK3args, xdr_nfslog_LINK3res, TRUE},
+
+	/* NFSPROC3_READDIR = 16 */
+	{xdr_nfslog_READDIR3args, xdr_nfslog_READDIR3res, TRUE},
+
+	/* NFSPROC3_READDIRPLUS = 17 */
+	{xdr_nfslog_READDIRPLUS3args, xdr_nfslog_READDIRPLUS3res, TRUE},
+
+	/* NFSPROC3_FSSTAT = 18 */
+	{xdr_nfslog_FSSTAT3args, xdr_nfslog_FSSTAT3res, FALSE},
+
+	/* NFSPROC3_FSINFO = 19 */
+	{xdr_nfslog_FSINFO3args, xdr_nfslog_FSINFO3res, FALSE},
+
+	/* NFSPROC3_PATHCONF = 20 */
+	{xdr_nfslog_PATHCONF3args, xdr_nfslog_PATHCONF3res, FALSE},
+
+	/* NFSPROC3_COMMIT = 21 */
+	{xdr_nfslog_COMMIT3args, xdr_nfslog_COMMIT3res, FALSE},
+};
+
+static struct nfslog_proc_disp nfslog_proc_v1[] = {
+	/*
+	 * NFSLOG VERSION 1
+	 */
+
+	/* NFSLOG_NULL = 0 */
+	{xdr_void, xdr_void, TRUE},
+
+	/* NFSLOG_SHARE = 1 */
+	{xdr_nfslog_sharefsargs, xdr_nfslog_sharefsres, TRUE},
+
+	/* NFSLOG_UNSHARE = 2 */
+	{xdr_nfslog_sharefsargs, xdr_nfslog_sharefsres, TRUE},
+
+	/* NFSLOG_LOOKUP = 3 */
+	{xdr_nfslog_diropargs3, xdr_nfslog_LOOKUP3res, TRUE},
+
+	/* NFSLOG_GETFH = 4 */
+	{xdr_nfslog_getfhargs, xdr_nfsstat, TRUE},
+};
+
+static struct nfslog_vers_disp nfslog_vers_disptable[] = {
+	{sizeof (nfslog_proc_v2) / sizeof (nfslog_proc_v2[0]),
+	    nfslog_proc_v2},
+	{sizeof (nfslog_proc_v3) / sizeof (nfslog_proc_v3[0]),
+	    nfslog_proc_v3},
+};
+
+static struct nfslog_vers_disp nfslog_nfslog_vers_disptable[] = {
+	{sizeof (nfslog_proc_v1) / sizeof (nfslog_proc_v1[0]),
+	    nfslog_proc_v1},
+};
+
+static struct nfslog_prog_disp nfslog_dispatch_table[] = {
+	{NFS_PROGRAM, NFS_VERSMIN,
+		(sizeof (nfslog_vers_disptable) /
+		sizeof (nfslog_vers_disptable[0])),
+		nfslog_vers_disptable},
+
+	{NFSLOG_PROGRAM, NFSLOG_VERSMIN,
+		(sizeof (nfslog_nfslog_vers_disptable) /
+		sizeof (nfslog_nfslog_vers_disptable[0])),
+		nfslog_nfslog_vers_disptable},
+};
+
+static int	nfslog_dispatch_table_arglen = sizeof (nfslog_dispatch_table) /
+					sizeof (nfslog_dispatch_table[0]);
+
+/*
+ * This function will determine the appropriate export info struct to use
+ * and allocate a record id to be used in the written log buffer.
+ * Usually this is a straightforward operation but the existence of the
+ * multicomponent lookup and its semantics of crossing file system
+ * boundaries add to the complexity.  See the comments below...
+ */
+struct exportinfo *
+nfslog_get_exi(
+	struct exportinfo *exi,
+	struct svc_req *req,
+	caddr_t res,
+	unsigned int *nfslog_rec_id)
+{
+	struct log_buffer *lb;
+	struct exportinfo *exi_ret = NULL;
+	fhandle_t		*fh = NULL;
+	nfs_fh3			*fh3;
+
+	if (exi == NULL)
+		return (NULL);
+
+	/*
+	 * If the exi is marked for logging, allocate a record id and return
+	 */
+	if (exi->exi_export.ex_flags & EX_LOG) {
+		lb = exi->exi_logbuffer;
+
+		/* obtain the unique record id for the caller */
+		*nfslog_rec_id = atomic_add_32_nv(&lb->lb_rec_id, (int32_t)1);
+
+		/*
+		 * The caller will expect to be able to exi_rele() it,
+		 * so exi->exi_count must be incremented before it can
+		 * be returned, to make it uniform with exi_ret->exi_count
+		 */
+		mutex_enter(&exi->exi_lock);
+		exi->exi_count++;
+		mutex_exit(&exi->exi_lock);
+
+		return (exi);
+	}
+
+	if (exi != exi_public)
+		return (NULL);
+
+	/*
+	 * Here we have an exi that is not marked for logging.
+	 * It is possible that this request is a multicomponent lookup
+	 * that was done from the public file handle (not logged) and
+	 * the resulting file handle being returned to the client exists
+	 * in a file system that is being logged.  If this is the case
+	 * we need to log this multicomponent lookup to the appropriate
+	 * log buffer.  This will allow for the appropriate path name
+	 * mapping to occur at user level.
+	 */
+	if (req->rq_prog == NFS_PROGRAM) {
+		switch (req->rq_vers) {
+		case NFS_V3:
+			if ((req->rq_proc == NFSPROC3_LOOKUP) &&
+				(((LOOKUP3res *)res)->status == NFS3_OK)) {
+				fh3 = &((LOOKUP3res *)res)->res_u.ok.object;
+				if (fh3->fh3_length == sizeof (fhandle_t))
+					fh = &fh3->fh3_u.nfs_fh3_i.fh3_i;
+			}
+			break;
+
+		case NFS_VERSION:
+			if ((req->rq_proc == RFS_LOOKUP) &&
+				(((struct nfsdiropres *)
+					res)->dr_status == NFS_OK)) {
+				fh =
+		&((struct nfsdiropres *)res)->dr_u.dr_drok_u.drok_fhandle;
+			}
+			break;
+		default:
+			break;
+		}
+		if (fh != NULL) {
+			exi_ret = checkexport(&fh->fh_fsid,
+				(fid_t *)&fh->fh_xlen);
+		}
+	}
+
+	if (exi_ret != NULL && exi_ret->exi_export.ex_flags & EX_LOG) {
+		lb = exi_ret->exi_logbuffer;
+		/* obtain the unique record id for the caller */
+		*nfslog_rec_id = atomic_add_32_nv(&lb->lb_rec_id, (int32_t)1);
+
+		return (exi_ret);
+	}
+	return (NULL);
+}
+
+#ifdef DEBUG
+static long long rfslog_records_ignored = 0;
+#endif
+
+/*
+ * nfslog_write_record - Fill in the record buffer for writing out.
+ * If logrecp is null, log it, otherwise, malloc the record and return it.
+ *
+ * It is the responsibility of the caller to check whether this exportinfo
+ * has logging enabled.
+ * Note that nfslog_share_public_record() only needs to check for the
+ * existence of at least one logbuffer to which the public filehandle record
+ * needs to be logged.
+ */
+void
+nfslog_write_record(struct exportinfo *exi, struct svc_req *req,
+	caddr_t args, caddr_t res, cred_t *cr, struct netbuf *pnb,
+	unsigned int record_id, unsigned int which_buffers)
+{
+	struct nfslog_prog_disp	*progtable;	/* prog struct */
+	struct nfslog_vers_disp	*verstable;	/* version struct */
+	struct nfslog_proc_disp	*disp = NULL;	/* proc struct */
+	int			i, vers;
+	void			*log_cookie;	/* for logrecord if */
+	caddr_t			buffer;
+	XDR			xdrs;
+	unsigned int		final_size;
+	int			encode_ok;
+	int			alloc_indx;
+
+	ASSERT(exi != NULL); ASSERT(req != NULL); ASSERT(args != NULL);
+	ASSERT(res != NULL); ASSERT(cr != NULL);
+
+	/*
+	 * Find program element
+	 * Search the list since program can not be used as index
+	 */
+	for (i = 0; (i < nfslog_dispatch_table_arglen); i++) {
+		if (req->rq_prog == nfslog_dispatch_table[i].nfslog_dis_prog)
+			break;
+	}
+	if (i >= nfslog_dispatch_table_arglen) {	/* program not logged */
+		/* not an error */
+		return;
+	}
+
+	/*
+	 * Extract the dispatch functions based on program/version
+	 */
+	progtable = &nfslog_dispatch_table[i];
+	vers = req->rq_vers - progtable->nfslog_dis_versmin;
+	verstable = &progtable->nfslog_dis_vers_table[vers];
+	disp = &verstable->nfslog_dis_proc_table[req->rq_proc];
+
+	if (!(exi->exi_export.ex_flags & EX_LOG_ALLOPS) &&
+	    !disp->affects_transactions) {
+		/*
+		 * Only interested in logging operations affecting
+		 * transaction generation. This is not one of them.
+		 */
+#ifdef DEBUG
+		rfslog_records_ignored++;
+#endif
+		return;
+	}
+
+	switch (req->rq_prog) {
+	case NFS_PROGRAM:
+		switch (req->rq_vers) {
+		case NFS_V3:
+			switch (req->rq_proc) {
+			case NFSPROC3_READDIRPLUS:
+				alloc_indx = MEDIUM_INDX;
+				break;
+			default:
+				alloc_indx = SMALL_INDX;
+				break;
+			}
+			break;
+		default:
+			alloc_indx = SMALL_INDX;
+			break;
+		}
+		break;
+	case NFSLOG_PROGRAM:
+		alloc_indx = MEDIUM_INDX;
+		break;
+	default:
+		alloc_indx = SMALL_INDX;
+		break;
+	}
+
+	do {
+		encode_ok = FALSE;
+
+		/* Pick the size to alloc; end of the road - return */
+		if (nfslog_mem_alloc[alloc_indx].size == (-1)) {
+			cmn_err(CE_WARN,
+				"NFSLOG: unable to encode record - prog=%d "
+				"proc = %d", req->rq_prog, req->rq_proc);
+			return;
+		}
+
+		buffer = nfslog_record_alloc(exi, alloc_indx, &log_cookie, 0);
+		if (buffer == NULL) {
+			/* Error processing - no space alloced */
+			rfs_log_bad++;
+			cmn_err(CE_WARN, "NFSLOG: can't get record");
+			return;
+		}
+
+		xdrmem_create(&xdrs, buffer,
+			nfslog_mem_alloc[alloc_indx].size, XDR_ENCODE);
+
+		/*
+		 * Encode the header, args and results of the record
+		 */
+		if (xdr_nfslog_request_record(&xdrs, exi, req, cr, pnb,
+			nfslog_mem_alloc[alloc_indx].size, record_id) &&
+			(*disp->xdrargs)(&xdrs, args) &&
+			(*disp->xdrres)(&xdrs, res)) {
+				encode_ok = TRUE;
+
+				rfs_log_good++;
+				/*
+				 * Get the final size of the encoded
+				 * data and insert that length at the
+				 * beginning.
+				 */
+				final_size = xdr_getpos(&xdrs);
+				xdr_setpos(&xdrs, 0);
+				(void) xdr_u_int(&xdrs, &final_size);
+		} else {
+			/* Oops, the encode failed so we need to free memory */
+			nfslog_record_put(log_cookie, 0, FALSE, which_buffers);
+			alloc_indx++;
+		}
+
+	} while (encode_ok == FALSE);
+
+
+	/*
+	 * Take the final log record and put it in the log file.
+	 * This may be queued to the file internally and written
+	 * later unless the last parameter is TRUE.
+	 * If the record_id is 0 then this is most likely a share/unshare
+	 * request and it should be written synchronously to the log file.
+	 */
+	nfslog_record_put(log_cookie, final_size,
+		(record_id == 0), which_buffers);
+}
+
+static char *
+get_publicfh_path(int *alloc_length)
+{
+	extern struct exportinfo *exi_public;
+	char *pubpath;
+
+	rw_enter(&exported_lock, RW_READER);
+
+	*alloc_length = exi_public->exi_export.ex_pathlen + 1;
+	pubpath = kmem_alloc(*alloc_length, KM_SLEEP);
+
+	(void) strcpy(pubpath, exi_public->exi_export.ex_path);
+
+	rw_exit(&exported_lock);
+
+	return (pubpath);
+}
+
+static void
+log_public_record(struct exportinfo *exi, cred_t *cr)
+{
+	struct svc_req	req;
+	struct netbuf	nb = {0, 0, NULL};
+	int free_length = 0;
+	diropargs3 args;
+	LOOKUP3res res;
+
+	bzero(&req, sizeof (req));
+	req.rq_prog = NFSLOG_PROGRAM;
+	req.rq_vers = NFSLOG_VERSION;
+	req.rq_proc = NFSLOG_LOOKUP;
+	req.rq_cred.oa_flavor = AUTH_NONE;
+
+	bzero(&args, sizeof (diropargs3));
+	bzero(&res, sizeof (LOOKUP3res));
+
+	args.dir.fh3_length = 0;
+	if ((args.name = get_publicfh_path(&free_length)) == NULL)
+		return;
+	args.dirp = &args.dir;
+
+	res.status = NFS3_OK;
+	res.res_u.ok.object.fh3_length = 0;
+
+	/*
+	 * Calling this function with the exi_public
+	 * will have the effect of appending the record
+	 * to each of the open log buffers
+	 */
+	nfslog_write_record(exi, &req,
+		(caddr_t)&args, (caddr_t)&res, cr, &nb, 0, NFSLOG_ALL_BUFFERS);
+
+	kmem_free(args.name, free_length);
+}
+
+/*
+ * nfslog_share_record - logs a share request.
+ * This is not an NFS request, but we pretend here...
+ */
+void
+nfslog_share_record(struct exportinfo *exi, cred_t *cr)
+{
+	struct svc_req	req;
+	int		res = 0;
+	struct netbuf	nb = {0, 0, NULL};
+
+	ASSERT(exi != NULL);
+
+	if (nfslog_buffer_list == NULL)
+		return;
+
+	if (exi->exi_export.ex_flags & EX_LOG) {
+		bzero(&req, sizeof (req));
+		req.rq_prog = NFSLOG_PROGRAM;
+		req.rq_vers = NFSLOG_VERSION;
+		req.rq_proc = NFSLOG_SHARE;
+		req.rq_cred.oa_flavor = AUTH_NONE;
+		nfslog_write_record(exi, &req,
+			(caddr_t)exi, (caddr_t)&res, cr,
+			&nb, 0, NFSLOG_ONE_BUFFER);
+	}
+
+	log_public_record(exi, cr);
+}
+
+/*
+ * nfslog_unshare_record - logs an unshare request.
+ * This is not an NFS request, but we pretend here...
+ */
+void
+nfslog_unshare_record(struct exportinfo *exi, cred_t *cr)
+{
+	struct svc_req	req;
+	int		res = 0;
+	struct netbuf	nb = {0, 0, NULL};
+
+	ASSERT(exi != NULL);
+	ASSERT(exi->exi_export.ex_flags & EX_LOG);
+
+	bzero(&req, sizeof (req));
+	req.rq_prog = NFSLOG_PROGRAM;
+	req.rq_vers = NFSLOG_VERSION;
+	req.rq_proc = NFSLOG_UNSHARE;
+	req.rq_cred.oa_flavor = AUTH_NONE;
+	nfslog_write_record(exi, &req,
+		(caddr_t)exi, (caddr_t)&res, cr, &nb, 0, NFSLOG_ONE_BUFFER);
+}
+
+
+void
+nfslog_getfh(struct exportinfo *exi,
+	fhandle *fh,
+	char *fname,
+	enum uio_seg seg,
+	cred_t *cr)
+{
+	struct svc_req	req;
+	int		res = 0;
+	struct netbuf	nb = {0, 0, NULL};
+	int		error = 0;
+	char		*namebuf;
+	size_t		len;
+	nfslog_getfhargs gfh;
+
+	ASSERT(exi != NULL);
+	ASSERT(exi->exi_export.ex_flags & EX_LOG);
+
+	bzero(&req, sizeof (req));
+	req.rq_prog = NFSLOG_PROGRAM;
+	req.rq_vers = NFSLOG_VERSION;
+	req.rq_proc = NFSLOG_GETFH;
+	req.rq_cred.oa_flavor = AUTH_NONE;
+
+	namebuf = kmem_alloc(MAXPATHLEN + 4, KM_SLEEP);
+	if (seg == UIO_USERSPACE) {
+		error = copyinstr(fname, namebuf, MAXPATHLEN, &len);
+	} else {
+		error = copystr(fname, namebuf, MAXPATHLEN, &len);
+	}
+
+	if (!error) {
+		gfh.gfh_fh_buf = *fh;
+		gfh.gfh_path = namebuf;
+
+		nfslog_write_record(exi, &req,
+			(caddr_t)&gfh, (caddr_t)&res, cr, &nb, 0,
+			NFSLOG_ONE_BUFFER);
+	}
+	kmem_free(namebuf, MAXPATHLEN + 4);
+}