[PATCH 08/17] mpt2sas: Added sysfs support for trace buffer

Kashyap, Desai
2010-06-17T08:48:55Z

Added support so the diag ring buffer can be pulled via sysfs
Added three new shost attributes: host_trace_buffer,
host_trace_buffer_enable, and host_trace_buffer_size. The
host_trace_buffer_enable attribute is used to either post or release
the trace buffers. The host_trace_buffer_size attribute contains
the size of the trace buffer. The host_trace_buffer atttribute contains
a maximum 4KB window of the buffer. In order to read the entire host buffer,
you will need to write the offset to host_trace_buffer prior to reading
it. release the host buffer, then write the entire host buffer contents to
a file.
In addition to this enhancement, we moved the automatic posting of host buffers
at driver load time to be called prior to port_enable, instead of after.
That way discovery is available in the host buffer.

Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
---
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 88befc7..93c0623 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -3529,8 +3529,12 @@ _base_make_ioc_operational(struct MPT2SAS_ADAPTER *ioc, int sleep_flag)
if (sleep_flag == CAN_SLEEP)
_base_static_config_pages(ioc);

- if (ioc->wait_for_port_enable_to_complete && disable_discovery > 0)
- return r;
+ if (ioc->wait_for_port_enable_to_complete) {
+ if (diag_buffer_enable != 0)
+ mpt2sas_enable_diag_buffer(ioc, diag_buffer_enable);
+ if (disable_discovery > 0)
+ return r;
+ }

r = _base_send_port_enable(ioc, sleep_flag);
if (r)
@@ -3679,8 +3683,6 @@ mpt2sas_base_attach(struct MPT2SAS_ADAPTER *ioc)
goto out_free_resources;

mpt2sas_base_start_watchdog(ioc);
- if (diag_buffer_enable != 0)
- mpt2sas_enable_diag_buffer(ioc, diag_buffer_enable);
return 0;

out_free_resources:
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index ad277f3..d201c20 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -750,6 +750,8 @@ struct MPT2SAS_ADAPTER {
Mpi2ManufacturingPage10_t manu_pg10;
u32 product_specific[MPI2_DIAG_BUF_TYPE_COUNT][23];
u32 diagnostic_flags[MPI2_DIAG_BUF_TYPE_COUNT];
+ u32 ring_buffer_offset;
+ u32 ring_buffer_sz;
};

typedef u8 (*MPT_CALLBACK)(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index,
diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
index 25c866e..371f063 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
@@ -2603,6 +2603,195 @@ _ctl_ioc_reset_count_show(struct device *cdev, struct device_attribute *attr,
static DEVICE_ATTR(ioc_reset_count, S_IRUGO,
_ctl_ioc_reset_count_show, NULL);

+struct DIAG_BUFFER_START {
+ u32 Size;
+ u32 DiagVersion;
+ u8 BufferType;
+ u8 Reserved[3];
+ u32 Reserved1;
+ u32 Reserved2;
+ u32 Reserved3;
+};
+/**
+ * _ctl_host_trace_buffer_size_show - host buffer size (trace only)
+ * @cdev - pointer to embedded class device
+ * @buf - the buffer returned
+ *
+ * A sysfs 'read-only' shost attribute.
+ */
+static ssize_t
+_ctl_host_trace_buffer_size_show(struct device *cdev,
+ struct device_attribute *attr, char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(cdev);
+ struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+ u32 size = 0;
+ struct DIAG_BUFFER_START *request_data;
+
+ if (!ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE]) {
+ printk(MPT2SAS_ERR_FMT "%s: host_trace_buffer is not "
+ "registered\n", ioc->name, __func__);
+ return 0;
+ }
+
+ if ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_REGISTERED) == 0) {
+ printk(MPT2SAS_ERR_FMT "%s: host_trace_buffer is not "
+ "registered\n", ioc->name, __func__);
+ return 0;
+ }
+
+ request_data = (struct DIAG_BUFFER_START *)
+ ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE];
+ if ((le32_to_cpu(request_data->DiagVersion) == 0x00000000 ||
+ le32_to_cpu(request_data->DiagVersion) == 0x01000000) &&
+ le32_to_cpu(request_data->Reserved3) == 0x4742444c)
+ size = le32_to_cpu(request_data->Size);
+
+ ioc->ring_buffer_sz = size;
+ return snprintf(buf, PAGE_SIZE, "%d\n", size);
+}
+static DEVICE_ATTR(host_trace_buffer_size, S_IRUGO,
+ _ctl_host_trace_buffer_size_show, NULL);
+
+/**
+ * _ctl_host_trace_buffer_show - firmware ring buffer (trace only)
+ * @cdev - pointer to embedded class device
+ * @buf - the buffer returned
+ *
+ * A sysfs 'read/write' shost attribute.
+ *
+ * You will only be able to read 4k bytes of ring buffer at a time.
+ * In order to read beyond 4k bytes, you will have to write out the
+ * offset to the same attribute, it will move the pointer.
+ */
+static ssize_t
+_ctl_host_trace_buffer_show(struct device *cdev, struct device_attribute *attr,
+ char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(cdev);
+ struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+ void *request_data;
+ u32 size;
+
+ if (!ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE]) {
+ printk(MPT2SAS_ERR_FMT "%s: host_trace_buffer is not "
+ "registered\n", ioc->name, __func__);
+ return 0;
+ }
+
+ if ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_REGISTERED) == 0) {
+ printk(MPT2SAS_ERR_FMT "%s: host_trace_buffer is not "
+ "registered\n", ioc->name, __func__);
+ return 0;
+ }
+
+ if (ioc->ring_buffer_offset > ioc->ring_buffer_sz)
+ return 0;
+
+ size = ioc->ring_buffer_sz - ioc->ring_buffer_offset;
+ size = (size > PAGE_SIZE) ? PAGE_SIZE : size;
+ request_data = ioc->diag_buffer[0] + ioc->ring_buffer_offset;
+ memcpy(buf, request_data, size);
+ return size;
+}
+
+static ssize_t
+_ctl_host_trace_buffer_store(struct device *cdev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct Scsi_Host *shost = class_to_shost(cdev);
+ struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+ int val = 0;
+
+ if (sscanf(buf, "%d", &val) != 1)
+ return -EINVAL;
+
+ ioc->ring_buffer_offset = val;
+ return strlen(buf);
+}
+static DEVICE_ATTR(host_trace_buffer, S_IRUGO | S_IWUSR,
+ _ctl_host_trace_buffer_show, _ctl_host_trace_buffer_store);
+
+/*****************************************/
+
+/**
+ * _ctl_host_trace_buffer_enable_show - firmware ring buffer (trace only)
+ * @cdev - pointer to embedded class device
+ * @buf - the buffer returned
+ *
+ * A sysfs 'read/write' shost attribute.
+ *
+ * This is a mechnism to post/release host_trace_buffers
+ */
+static ssize_t
+_ctl_host_trace_buffer_enable_show(struct device *cdev,
+ struct device_attribute *attr, char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(cdev);
+ struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+
+ if ((!ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE]) ||
+ ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_REGISTERED) == 0))
+ return snprintf(buf, PAGE_SIZE, "off\n");
+ else if ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_RELEASED))
+ return snprintf(buf, PAGE_SIZE, "release\n");
+ else
+ return snprintf(buf, PAGE_SIZE, "post\n");
+}
+
+static ssize_t
+_ctl_host_trace_buffer_enable_store(struct device *cdev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct Scsi_Host *shost = class_to_shost(cdev);
+ struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+ char str[10] = "";
+ struct mpt2_diag_register diag_register;
+ u8 issue_reset = 0;
+
+ if (sscanf(buf, "%s", str) != 1)
+ return -EINVAL;
+
+ if (!strcmp(str, "post")) {
+ /* exit out if host buffers are already posted */
+ if ((ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE]) &&
+ (ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_REGISTERED) &&
+ ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_RELEASED) == 0))
+ goto out;
+ memset(&diag_register, 0, sizeof(struct mpt2_diag_register));
+ printk(MPT2SAS_INFO_FMT "posting host trace buffers\n",
+ ioc->name);
+ diag_register.buffer_type = MPI2_DIAG_BUF_TYPE_TRACE;
+ diag_register.requested_buffer_size = (1024 * 1024);
+ diag_register.unique_id = 0x7075900;
+ ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] = 0;
+ _ctl_diag_register_2(ioc, &diag_register);
+ } else if (!strcmp(str, "release")) {
+ /* exit out if host buffers are already released */
+ if (!ioc->diag_buffer[MPI2_DIAG_BUF_TYPE_TRACE])
+ goto out;
+ if ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_REGISTERED) == 0)
+ goto out;
+ if ((ioc->diag_buffer_status[MPI2_DIAG_BUF_TYPE_TRACE] &
+ MPT2_DIAG_BUFFER_IS_RELEASED))
+ goto out;
+ printk(MPT2SAS_INFO_FMT "releasing host trace buffer\n",
+ ioc->name);
+ _ctl_send_release(ioc, MPI2_DIAG_BUF_TYPE_TRACE, &issue_reset);
+ }
+
+ out:
+ return strlen(buf);
+}
+static DEVICE_ATTR(host_trace_buffer_enable, S_IRUGO | S_IWUSR,
+ _ctl_host_trace_buffer_enable_show, _ctl_host_trace_buffer_enable_store);

struct device_attribute *mpt2sas_host_attrs[] = {
&dev_attr_version_fw,
@@ -2621,6 +2810,9 @@ struct device_attribute *mpt2sas_host_attrs[] = {
&dev_attr_fw_queue_depth,
&dev_attr_host_sas_address,
&dev_attr_ioc_reset_count,
+ &dev_attr_host_trace_buffer_size,
+ &dev_attr_host_trace_buffer,
+ &dev_attr_host_trace_buffer_enable,
NULL,
};