These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / scsi / snic / snic_trc.c

diff --git a/kernel/drivers/scsi/snic/snic_trc.c b/kernel/drivers/scsi/snic/snic_trc.c
new file mode 100644 (file)
index 0000000..f00ebf4
--- /dev/null
+++ b/kernel/drivers/scsi/snic/snic_trc.c
@@ -0,0 +1,181 @@
+/*
+ * 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/mempool.h>
+#include <linux/errno.h>
+#include <linux/vmalloc.h>
+
+#include "snic_io.h"
+#include "snic.h"
+
+/*
+ * snic_get_trc_buf : Allocates a trace record and returns.
+ */
+struct snic_trc_data *
+snic_get_trc_buf(void)
+{
+       struct snic_trc *trc = &snic_glob->trc;
+       struct snic_trc_data *td = NULL;
+       unsigned long flags;
+
+       spin_lock_irqsave(&trc->lock, flags);
+       td = &trc->buf[trc->wr_idx];
+       trc->wr_idx++;
+
+       if (trc->wr_idx == trc->max_idx)
+               trc->wr_idx = 0;
+
+       if (trc->wr_idx != trc->rd_idx) {
+               spin_unlock_irqrestore(&trc->lock, flags);
+
+               goto end;
+       }
+
+       trc->rd_idx++;
+       if (trc->rd_idx == trc->max_idx)
+               trc->rd_idx = 0;
+
+       td->ts = 0;     /* Marker for checking the record, for complete data*/
+       spin_unlock_irqrestore(&trc->lock, flags);
+
+end:
+
+       return td;
+} /* end of snic_get_trc_buf */
+
+/*
+ * snic_fmt_trc_data : Formats trace data for printing.
+ */
+static int
+snic_fmt_trc_data(struct snic_trc_data *td, char *buf, int buf_sz)
+{
+       int len = 0;
+       struct timespec tmspec;
+
+       jiffies_to_timespec(td->ts, &tmspec);
+
+       len += snprintf(buf, buf_sz,
+                       "%lu.%10lu %-25s %3d %4x %16llx %16llx %16llx %16llx %16llx\n",
+                       tmspec.tv_sec,
+                       tmspec.tv_nsec,
+                       td->fn,
+                       td->hno,
+                       td->tag,
+                       td->data[0], td->data[1], td->data[2], td->data[3],
+                       td->data[4]);
+
+       return len;
+} /* end of snic_fmt_trc_data */
+
+/*
+ * snic_get_trc_data : Returns a formatted trace buffer.
+ */
+int
+snic_get_trc_data(char *buf, int buf_sz)
+{
+       struct snic_trc_data *td = NULL;
+       struct snic_trc *trc = &snic_glob->trc;
+       unsigned long flags;
+
+       spin_lock_irqsave(&trc->lock, flags);
+       if (trc->rd_idx == trc->wr_idx) {
+               spin_unlock_irqrestore(&trc->lock, flags);
+
+               return -1;
+       }
+       td = &trc->buf[trc->rd_idx];
+
+       if (td->ts == 0) {
+               /* write in progress. */
+               spin_unlock_irqrestore(&trc->lock, flags);
+
+               return -1;
+       }
+
+       trc->rd_idx++;
+       if (trc->rd_idx == trc->max_idx)
+               trc->rd_idx = 0;
+       spin_unlock_irqrestore(&trc->lock, flags);
+
+       return snic_fmt_trc_data(td, buf, buf_sz);
+} /* end of snic_get_trc_data */
+
+/*
+ * snic_trc_init() : Configures Trace Functionality for snic.
+ */
+int
+snic_trc_init(void)
+{
+       struct snic_trc *trc = &snic_glob->trc;
+       void *tbuf = NULL;
+       int tbuf_sz = 0, ret;
+
+       tbuf_sz = (snic_trace_max_pages * PAGE_SIZE);
+       tbuf = vmalloc(tbuf_sz);
+       if (!tbuf) {
+               SNIC_ERR("Failed to Allocate Trace Buffer Size. %d\n", tbuf_sz);
+               SNIC_ERR("Trace Facility not enabled.\n");
+               ret = -ENOMEM;
+
+               return ret;
+       }
+
+       memset(tbuf, 0, tbuf_sz);
+       trc->buf = (struct snic_trc_data *) tbuf;
+       spin_lock_init(&trc->lock);
+
+       ret = snic_trc_debugfs_init();
+       if (ret) {
+               SNIC_ERR("Failed to create Debugfs Files.\n");
+
+               goto error;
+       }
+
+       trc->max_idx = (tbuf_sz / SNIC_TRC_ENTRY_SZ);
+       trc->rd_idx = trc->wr_idx = 0;
+       trc->enable = true;
+       SNIC_INFO("Trace Facility Enabled.\n Trace Buffer SZ %lu Pages.\n",
+                 tbuf_sz / PAGE_SIZE);
+       ret = 0;
+
+       return ret;
+
+error:
+       snic_trc_free();
+
+       return ret;
+} /* end of snic_trc_init */
+
+/*
+ * snic_trc_free : Releases the trace buffer and disables the tracing.
+ */
+void
+snic_trc_free(void)
+{
+       struct snic_trc *trc = &snic_glob->trc;
+
+       trc->enable = false;
+       snic_trc_debugfs_term();
+
+       if (trc->buf) {
+               vfree(trc->buf);
+               trc->buf = NULL;
+       }
+
+       SNIC_INFO("Trace Facility Disabled.\n");
+} /* end of snic_trc_free */