snic: driver for Cisco SCSI HBA

Cisco has developed a new PCI HBA interface called sNIC, which stands for
SCSI NIC. This is a new storage feature supported on specialized network
adapter. The new PCI function provides a uniform host interface and abstracts
backend storage.

[jejb: fix up checkpatch errors]
Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 560 insertions, 0 deletions

diff --git a/drivers/scsi/snic/snic_debugfs.c b/drivers/scsi/snic/snic_debugfs.c
new file mode 100644
index 000000000000..1686f0196251
--- /dev/null
+++ b/drivers/scsi/snic/snic_debugfs.c
@@ -0,0 +1,560 @@
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/debugfs.h>
+
+#include "snic.h"
+
+/*
+ * snic_debugfs_init - Initialize debugfs for snic debug logging
+ *
+ * Description:
+ * When Debugfs is configured this routine sets up fnic debugfs
+ * filesystem. If not already created. this routine will crate the
+ * fnic directory and statistics directory for trace buffer and
+ * stats logging
+ */
+
+int
+snic_debugfs_init(void)
+{
+	int rc = -1;
+	struct dentry *de = NULL;
+
+	de = debugfs_create_dir("snic", NULL);
+	if (!de) {
+		SNIC_DBG("Cannot create debugfs root\n");
+
+		return rc;
+	}
+	snic_glob->trc_root = de;
+
+	de = debugfs_create_dir("statistics", snic_glob->trc_root);
+	if (!de) {
+		SNIC_DBG("Cannot create Statistics directory\n");
+
+		return rc;
+	}
+	snic_glob->stats_root = de;
+
+	rc = 0;
+
+	return rc;
+} /* end of snic_debugfs_init */
+
+/*
+ * snic_debugfs_term - Tear down debugfs intrastructure
+ *
+ * Description:
+ * When Debufs is configured this routine removes debugfs file system
+ * elements that are specific to snic
+ */
+void
+snic_debugfs_term(void)
+{
+	debugfs_remove(snic_glob->stats_root);
+	snic_glob->stats_root = NULL;
+
+	debugfs_remove(snic_glob->trc_root);
+	snic_glob->trc_root = NULL;
+}
+
+/*
+ * snic_reset_stats_open - Open the reset_stats file
+ */
+static int
+snic_reset_stats_open(struct inode *inode, struct file *filp)
+{
+	SNIC_BUG_ON(!inode->i_private);
+	filp->private_data = inode->i_private;
+
+	return 0;
+}
+
+/*
+ * snic_reset_stats_read - Read a reset_stats debugfs file
+ * @filp: The file pointer to read from.
+ * @ubuf: The buffer tocopy the data to.
+ * @cnt: The number of bytes to read.
+ * @ppos: The position in the file to start reading frm.
+ *
+ * Description:
+ * This routine reads value of variable reset_stats
+ * and stores into local @buf. It will start reading file @ppos and
+ * copy up to @cnt of data to @ubuf from @buf.
+ *
+ * Returns:
+ * This function returns the amount of data that was read.
+ */
+static ssize_t
+snic_reset_stats_read(struct file *filp,
+		      char __user *ubuf,
+		      size_t cnt,
+		      loff_t *ppos)
+{
+	struct snic *snic = (struct snic *) filp->private_data;
+	char buf[64];
+	int len;
+
+	len = sprintf(buf, "%u\n", snic->reset_stats);
+
+	return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
+}
+
+/*
+ * snic_reset_stats_write - Write to reset_stats debugfs file
+ * @filp: The file pointer to write from
+ * @ubuf: The buffer to copy the data from.
+ * @cnt: The number of bytes to write.
+ * @ppos: The position in the file to start writing to.
+ *
+ * Description:
+ * This routine writes data from user buffer @ubuf to buffer @buf and
+ * resets cumulative stats of snic.
+ *
+ * Returns:
+ * This function returns the amount of data that was written.
+ */
+static ssize_t
+snic_reset_stats_write(struct file *filp,
+		       const char __user *ubuf,
+		       size_t cnt,
+		       loff_t *ppos)
+{
+	struct snic *snic = (struct snic *) filp->private_data;
+	struct snic_stats *stats = &snic->s_stats;
+	u64 *io_stats_p = (u64 *) &stats->io;
+	u64 *fw_stats_p = (u64 *) &stats->fw;
+	char buf[64];
+	unsigned long val;
+	int ret;
+
+	if (cnt >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	buf[cnt] = '\0';
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret < 0)
+		return ret;
+
+	snic->reset_stats = val;
+
+	if (snic->reset_stats) {
+		/* Skip variable is used to avoid descrepancies to Num IOs
+		 * and IO Completions stats. Skip incrementing No IO Compls
+		 * for pending active IOs after reset_stats
+		 */
+		atomic64_set(&snic->io_cmpl_skip,
+			     atomic64_read(&stats->io.active));
+		memset(&stats->abts, 0, sizeof(struct snic_abort_stats));
+		memset(&stats->reset, 0, sizeof(struct snic_reset_stats));
+		memset(&stats->misc, 0, sizeof(struct snic_misc_stats));
+		memset(io_stats_p+1,
+			0,
+			sizeof(struct snic_io_stats) - sizeof(u64));
+		memset(fw_stats_p+1,
+			0,
+			sizeof(struct snic_fw_stats) - sizeof(u64));
+	}
+
+	(*ppos)++;
+
+	SNIC_HOST_INFO(snic->shost, "Reset Op: Driver statistics.\n");
+
+	return cnt;
+}
+
+static int
+snic_reset_stats_release(struct inode *inode, struct file *filp)
+{
+	filp->private_data = NULL;
+
+	return 0;
+}
+
+/*
+ * snic_stats_show - Formats and prints per host specific driver stats.
+ */
+static int
+snic_stats_show(struct seq_file *sfp, void *data)
+{
+	struct snic *snic = (struct snic *) sfp->private;
+	struct snic_stats *stats = &snic->s_stats;
+	struct timespec last_isr_tms, last_ack_tms;
+	u64 maxio_tm;
+	int i;
+
+	/* Dump IO Stats */
+	seq_printf(sfp,
+		   "------------------------------------------\n"
+		   "\t\t IO Statistics\n"
+		   "------------------------------------------\n");
+
+	maxio_tm = (u64) atomic64_read(&stats->io.max_time);
+	seq_printf(sfp,
+		   "Active IOs                  : %lld\n"
+		   "Max Active IOs              : %lld\n"
+		   "Total IOs                   : %lld\n"
+		   "IOs Completed               : %lld\n"
+		   "IOs Failed                  : %lld\n"
+		   "IOs Not Found               : %lld\n"
+		   "Memory Alloc Failures       : %lld\n"
+		   "REQs Null                   : %lld\n"
+		   "SCSI Cmd Pointers Null      : %lld\n"
+		   "Max SGL for any IO          : %lld\n"
+		   "Max IO Size                 : %lld Sectors\n"
+		   "Max Queuing Time            : %lld\n"
+		   "Max Completion Time         : %lld\n"
+		   "Max IO Process Time(FW)     : %lld (%u msec)\n",
+		   (u64) atomic64_read(&stats->io.active),
+		   (u64) atomic64_read(&stats->io.max_active),
+		   (u64) atomic64_read(&stats->io.num_ios),
+		   (u64) atomic64_read(&stats->io.compl),
+		   (u64) atomic64_read(&stats->io.fail),
+		   (u64) atomic64_read(&stats->io.io_not_found),
+		   (u64) atomic64_read(&stats->io.alloc_fail),
+		   (u64) atomic64_read(&stats->io.req_null),
+		   (u64) atomic64_read(&stats->io.sc_null),
+		   (u64) atomic64_read(&stats->io.max_sgl),
+		   (u64) atomic64_read(&stats->io.max_io_sz),
+		   (u64) atomic64_read(&stats->io.max_qtime),
+		   (u64) atomic64_read(&stats->io.max_cmpl_time),
+		   maxio_tm,
+		   jiffies_to_msecs(maxio_tm));
+
+	seq_puts(sfp, "\nSGL Counters\n");
+
+	for (i = 0; i < SNIC_MAX_SG_DESC_CNT; i++) {
+		seq_printf(sfp,
+			   "%10lld ",
+			   (u64) atomic64_read(&stats->io.sgl_cnt[i]));
+
+		if ((i + 1) % 8 == 0)
+			seq_puts(sfp, "\n");
+	}
+
+	/* Dump Abort Stats */
+	seq_printf(sfp,
+		   "\n-------------------------------------------\n"
+		   "\t\t Abort Statistics\n"
+		   "---------------------------------------------\n");
+
+	seq_printf(sfp,
+		   "Aborts                      : %lld\n"
+		   "Aborts Fail                 : %lld\n"
+		   "Aborts Driver Timeout       : %lld\n"
+		   "Abort FW Timeout            : %lld\n"
+		   "Abort IO NOT Found          : %lld\n",
+		   (u64) atomic64_read(&stats->abts.num),
+		   (u64) atomic64_read(&stats->abts.fail),
+		   (u64) atomic64_read(&stats->abts.drv_tmo),
+		   (u64) atomic64_read(&stats->abts.fw_tmo),
+		   (u64) atomic64_read(&stats->abts.io_not_found));
+
+	/* Dump Reset Stats */
+	seq_printf(sfp,
+		   "\n-------------------------------------------\n"
+		   "\t\t Reset Statistics\n"
+		   "---------------------------------------------\n");
+
+	seq_printf(sfp,
+		   "HBA Resets                  : %lld\n"
+		   "HBA Reset Cmpls             : %lld\n"
+		   "HBA Reset Fail              : %lld\n",
+		   (u64) atomic64_read(&stats->reset.hba_resets),
+		   (u64) atomic64_read(&stats->reset.hba_reset_cmpl),
+		   (u64) atomic64_read(&stats->reset.hba_reset_fail));
+
+	/* Dump Firmware Stats */
+	seq_printf(sfp,
+		   "\n-------------------------------------------\n"
+		   "\t\t Firmware Statistics\n"
+		   "---------------------------------------------\n");
+
+	seq_printf(sfp,
+		"Active FW Requests             : %lld\n"
+		"Max FW Requests                : %lld\n"
+		"FW Out Of Resource Errs        : %lld\n"
+		"FW IO Errors                   : %lld\n"
+		"FW SCSI Errors                 : %lld\n",
+		(u64) atomic64_read(&stats->fw.actv_reqs),
+		(u64) atomic64_read(&stats->fw.max_actv_reqs),
+		(u64) atomic64_read(&stats->fw.out_of_res),
+		(u64) atomic64_read(&stats->fw.io_errs),
+		(u64) atomic64_read(&stats->fw.scsi_errs));
+
+
+	/* Dump Miscellenous Stats */
+	seq_printf(sfp,
+		   "\n---------------------------------------------\n"
+		   "\t\t Other Statistics\n"
+		   "\n---------------------------------------------\n");
+
+	jiffies_to_timespec(stats->misc.last_isr_time, &last_isr_tms);
+	jiffies_to_timespec(stats->misc.last_ack_time, &last_ack_tms);
+
+	seq_printf(sfp,
+		   "Last ISR Time               : %llu (%8lu.%8lu)\n"
+		   "Last Ack Time               : %llu (%8lu.%8lu)\n"
+		   "ISRs                        : %llu\n"
+		   "Max CQ Entries              : %lld\n"
+		   "Data Count Mismatch         : %lld\n"
+		   "IOs w/ Timeout Status       : %lld\n"
+		   "IOs w/ Aborted Status       : %lld\n"
+		   "IOs w/ SGL Invalid Stat     : %lld\n"
+		   "WQ Desc Alloc Fail          : %lld\n"
+		   "Queue Full                  : %lld\n"
+		   "Target Not Ready            : %lld\n",
+		   (u64) stats->misc.last_isr_time,
+		   last_isr_tms.tv_sec, last_isr_tms.tv_nsec,
+		   (u64)stats->misc.last_ack_time,
+		   last_ack_tms.tv_sec, last_ack_tms.tv_nsec,
+		   (u64) atomic64_read(&stats->misc.isr_cnt),
+		   (u64) atomic64_read(&stats->misc.max_cq_ents),
+		   (u64) atomic64_read(&stats->misc.data_cnt_mismat),
+		   (u64) atomic64_read(&stats->misc.io_tmo),
+		   (u64) atomic64_read(&stats->misc.io_aborted),
+		   (u64) atomic64_read(&stats->misc.sgl_inval),
+		   (u64) atomic64_read(&stats->misc.wq_alloc_fail),
+		   (u64) atomic64_read(&stats->misc.qfull),
+		   (u64) atomic64_read(&stats->misc.tgt_not_rdy));
+
+	return 0;
+}
+
+/*
+ * snic_stats_open - Open the stats file for specific host
+ *
+ * Description:
+ * This routine opens a debugfs file stats of specific host
+ */
+static int
+snic_stats_open(struct inode *inode, struct file *filp)
+{
+	return single_open(filp, snic_stats_show, inode->i_private);
+}
+
+static const struct file_operations snic_stats_fops = {
+	.owner	= THIS_MODULE,
+	.open	= snic_stats_open,
+	.read	= seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static const struct file_operations snic_reset_stats_fops = {
+	.owner = THIS_MODULE,
+	.open = snic_reset_stats_open,
+	.read = snic_reset_stats_read,
+	.write = snic_reset_stats_write,
+	.release = snic_reset_stats_release,
+};
+
+/*
+ * snic_stats_init - Initialize stats struct and create stats file
+ * per snic
+ *
+ * Description:
+ * When debugfs is cofigured this routine sets up the stats file per snic
+ * It will create file stats and reset_stats under statistics/host# directory
+ * to log per snic stats
+ */
+int
+snic_stats_debugfs_init(struct snic *snic)
+{
+	int rc = -1;
+	char name[16];
+	struct dentry *de = NULL;
+
+	snprintf(name, sizeof(name), "host%d", snic->shost->host_no);
+	if (!snic_glob->stats_root) {
+		SNIC_DBG("snic_stats root doesn't exist\n");
+
+		return rc;
+	}
+
+	de = debugfs_create_dir(name, snic_glob->stats_root);
+	if (!de) {
+		SNIC_DBG("Cannot create host directory\n");
+
+		return rc;
+	}
+	snic->stats_host = de;
+
+	de = debugfs_create_file("stats",
+				S_IFREG|S_IRUGO,
+				snic->stats_host,
+				snic,
+				&snic_stats_fops);
+	if (!de) {
+		SNIC_DBG("Cannot create host's stats file\n");
+
+		return rc;
+	}
+	snic->stats_file = de;
+
+	de = debugfs_create_file("reset_stats",
+				S_IFREG|S_IRUGO|S_IWUSR,
+				snic->stats_host,
+				snic,
+				&snic_reset_stats_fops);
+
+	if (!de) {
+		SNIC_DBG("Cannot create host's reset_stats file\n");
+
+		return rc;
+	}
+	snic->reset_stats_file = de;
+	rc = 0;
+
+	return rc;
+} /* end of snic_stats_debugfs_init */
+
+/*
+ * snic_stats_debugfs_remove - Tear down debugfs infrastructure of stats
+ *
+ * Description:
+ * When Debufs is configured this routine removes debugfs file system
+ * elements that are specific to to snic stats
+ */
+void
+snic_stats_debugfs_remove(struct snic *snic)
+{
+	debugfs_remove(snic->stats_file);
+	snic->stats_file = NULL;
+
+	debugfs_remove(snic->reset_stats_file);
+	snic->reset_stats_file = NULL;
+
+	debugfs_remove(snic->stats_host);
+	snic->stats_host = NULL;
+}
+
+/* Trace Facility related API */
+static void *
+snic_trc_seq_start(struct seq_file *sfp, loff_t *pos)
+{
+	return &snic_glob->trc;
+}
+
+static void *
+snic_trc_seq_next(struct seq_file *sfp, void *data, loff_t *pos)
+{
+	return NULL;
+}
+
+static void
+snic_trc_seq_stop(struct seq_file *sfp, void *data)
+{
+}
+
+#define SNIC_TRC_PBLEN	256
+static int
+snic_trc_seq_show(struct seq_file *sfp, void *data)
+{
+	char buf[SNIC_TRC_PBLEN];
+
+	if (snic_get_trc_data(buf, SNIC_TRC_PBLEN) > 0)
+		seq_printf(sfp, "%s\n", buf);
+
+	return 0;
+}
+
+static const struct seq_operations snic_trc_seq_ops = {
+	.start	= snic_trc_seq_start,
+	.next	= snic_trc_seq_next,
+	.stop	= snic_trc_seq_stop,
+	.show	= snic_trc_seq_show,
+};
+
+static int
+snic_trc_open(struct inode *inode, struct file *filp)
+{
+	return seq_open(filp, &snic_trc_seq_ops);
+}
+
+static const struct file_operations snic_trc_fops = {
+	.owner	= THIS_MODULE,
+	.open	= snic_trc_open,
+	.read	= seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release,
+};
+
+/*
+ * snic_trc_debugfs_init : creates trace/tracing_enable files for trace
+ * under debugfs
+ */
+int
+snic_trc_debugfs_init(void)
+{
+	struct dentry *de = NULL;
+	int ret = -1;
+
+	if (!snic_glob->trc_root) {
+		SNIC_ERR("Debugfs root directory for snic doesn't exist.\n");
+
+		return ret;
+	}
+
+	de = debugfs_create_bool("tracing_enable",
+				 S_IFREG | S_IRUGO | S_IWUSR,
+				 snic_glob->trc_root,
+				 &snic_glob->trc.enable);
+
+	if (!de) {
+		SNIC_ERR("Can't create trace_enable file.\n");
+
+		return ret;
+	}
+	snic_glob->trc.trc_enable = de;
+
+	de = debugfs_create_file("trace",
+				 S_IFREG | S_IRUGO | S_IWUSR,
+				 snic_glob->trc_root,
+				 NULL,
+				 &snic_trc_fops);
+
+	if (!de) {
+		SNIC_ERR("Cann't create trace file.\n");
+
+		return ret;
+	}
+	snic_glob->trc.trc_file = de;
+	ret = 0;
+
+	return ret;
+} /* end of snic_trc_debugfs_init */
+
+/*
+ * snic_trc_debugfs_term : cleans up the files created for trace under debugfs
+ */
+void
+snic_trc_debugfs_term(void)
+{
+	debugfs_remove(snic_glob->trc.trc_file);
+	snic_glob->trc.trc_file = NULL;
+
+	debugfs_remove(snic_glob->trc.trc_enable);
+	snic_glob->trc.trc_enable = NULL;
+}