[PATCH 06/13] scsi: hisi_sas: Create a scsi_host_template per HW module

From: John Garry
Date: Mon May 21 2018 - 05:16:52 EST


From: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>

When a SCSI host is registered, the SCSI mid-layer takes
a reference to a module in Scsi_host.hostt.module. In doing
this, we are prevented from removing the driver module for
the host in dangerous scenario, like when a disk is mounted.

Currently there is only one scsi_host_template (sht) for
all HW versions, and this is the main.c module. So this means
that we can possibly remove the HW module in this dangerous
scenario, as SCSI mid-layer is only referencing the main.c
module.

To fix this, create a sht per module, referencing that same
module to create the Scsi host.

Signed-off-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas.h | 8 +++++--
drivers/scsi/hisi_sas/hisi_sas_main.c | 40 +++++++++-------------------------
drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 23 +++++++++++++++++++
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 24 ++++++++++++++++++++
drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 24 +++++++++++++++++++-
5 files changed, 86 insertions(+), 33 deletions(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index b4717bd..37c9a62 100644
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -248,6 +248,7 @@ struct hisi_sas_hw {
u8 reg_index, u8 reg_count, u8 *write_data);
int max_command_entries;
int complete_hdr_size;
+ struct scsi_host_template *sht;
};

struct hisi_hba {
@@ -440,8 +441,6 @@ struct hisi_sas_slot_buf_table {
};

extern struct scsi_transport_template *hisi_sas_stt;
-extern struct scsi_host_template *hisi_sas_sht;
-
extern void hisi_sas_stop_phys(struct hisi_hba *hisi_hba);
extern int hisi_sas_alloc(struct hisi_hba *hisi_hba, struct Scsi_Host *shost);
extern void hisi_sas_free(struct hisi_hba *hisi_hba);
@@ -456,6 +455,11 @@ extern int hisi_sas_probe(struct platform_device *pdev,
const struct hisi_sas_hw *ops);
extern int hisi_sas_remove(struct platform_device *pdev);

+extern int hisi_sas_slave_configure(struct scsi_device *sdev);
+extern int hisi_sas_scan_finished(struct Scsi_Host *shost, unsigned long time);
+extern void hisi_sas_scan_start(struct Scsi_Host *shost);
+extern struct device_attribute *host_attrs[];
+extern int hisi_sas_host_reset(struct Scsi_Host *shost, int reset_type);
extern void hisi_sas_phy_down(struct hisi_hba *hisi_hba, int phy_no, int rdy);
extern void hisi_sas_slot_task_free(struct hisi_hba *hisi_hba,
struct sas_task *task,
diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 0596553..7b8623b 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -719,7 +719,7 @@ static int hisi_sas_dev_found(struct domain_device *device)
return rc;
}

-static int hisi_sas_slave_configure(struct scsi_device *sdev)
+int hisi_sas_slave_configure(struct scsi_device *sdev)
{
struct domain_device *dev = sdev_to_domain_dev(sdev);
int ret = sas_slave_configure(sdev);
@@ -731,15 +731,17 @@ static int hisi_sas_slave_configure(struct scsi_device *sdev)

return 0;
}
+EXPORT_SYMBOL_GPL(hisi_sas_slave_configure);

-static void hisi_sas_scan_start(struct Scsi_Host *shost)
+void hisi_sas_scan_start(struct Scsi_Host *shost)
{
struct hisi_hba *hisi_hba = shost_priv(shost);

hisi_hba->hw->phys_init(hisi_hba);
}
+EXPORT_SYMBOL_GPL(hisi_sas_scan_start);

-static int hisi_sas_scan_finished(struct Scsi_Host *shost, unsigned long time)
+int hisi_sas_scan_finished(struct Scsi_Host *shost, unsigned long time)
{
struct hisi_hba *hisi_hba = shost_priv(shost);
struct sas_ha_struct *sha = &hisi_hba->sha;
@@ -751,6 +753,7 @@ static int hisi_sas_scan_finished(struct Scsi_Host *shost, unsigned long time)
sas_drain_work(sha);
return 1;
}
+EXPORT_SYMBOL_GPL(hisi_sas_scan_finished);

static void hisi_sas_phyup_work(struct work_struct *work)
{
@@ -1824,34 +1827,11 @@ void hisi_sas_kill_tasklets(struct hisi_hba *hisi_hba)
struct scsi_transport_template *hisi_sas_stt;
EXPORT_SYMBOL_GPL(hisi_sas_stt);

-static struct device_attribute *host_attrs[] = {
+struct device_attribute *host_attrs[] = {
&dev_attr_phy_event_threshold,
NULL,
};
-
-static struct scsi_host_template _hisi_sas_sht = {
- .module = THIS_MODULE,
- .name = DRV_NAME,
- .queuecommand = sas_queuecommand,
- .target_alloc = sas_target_alloc,
- .slave_configure = hisi_sas_slave_configure,
- .scan_finished = hisi_sas_scan_finished,
- .scan_start = hisi_sas_scan_start,
- .change_queue_depth = sas_change_queue_depth,
- .bios_param = sas_bios_param,
- .can_queue = 1,
- .this_id = -1,
- .sg_tablesize = SG_ALL,
- .max_sectors = SCSI_DEFAULT_MAX_SECTORS,
- .use_clustering = ENABLE_CLUSTERING,
- .eh_device_reset_handler = sas_eh_device_reset_handler,
- .eh_target_reset_handler = sas_eh_target_reset_handler,
- .target_destroy = sas_target_destroy,
- .ioctl = sas_ioctl,
- .shost_attrs = host_attrs,
-};
-struct scsi_host_template *hisi_sas_sht = &_hisi_sas_sht;
-EXPORT_SYMBOL_GPL(hisi_sas_sht);
+EXPORT_SYMBOL_GPL(host_attrs);

static struct sas_domain_function_template hisi_sas_transport_ops = {
.lldd_dev_found = hisi_sas_dev_found,
@@ -2161,7 +2141,7 @@ static struct Scsi_Host *hisi_sas_shost_alloc(struct platform_device *pdev,
struct hisi_hba *hisi_hba;
struct device *dev = &pdev->dev;

- shost = scsi_host_alloc(hisi_sas_sht, sizeof(*hisi_hba));
+ shost = scsi_host_alloc(hw->sht, sizeof(*hisi_hba));
if (!shost) {
dev_err(dev, "scsi host alloc failed\n");
return NULL;
@@ -2211,7 +2191,7 @@ static struct Scsi_Host *hisi_sas_shost_alloc(struct platform_device *pdev,
}

int hisi_sas_probe(struct platform_device *pdev,
- const struct hisi_sas_hw *hw)
+ const struct hisi_sas_hw *hw)
{
struct Scsi_Host *shost;
struct hisi_hba *hisi_hba;
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
index 8fa79d0..8d5d857 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
@@ -1788,6 +1788,28 @@ static int hisi_sas_v1_init(struct hisi_hba *hisi_hba)
return 0;
}

+static struct scsi_host_template sht_v1_hw = {
+ .name = DRV_NAME,
+ .module = THIS_MODULE,
+ .queuecommand = sas_queuecommand,
+ .target_alloc = sas_target_alloc,
+ .slave_configure = hisi_sas_slave_configure,
+ .scan_finished = hisi_sas_scan_finished,
+ .scan_start = hisi_sas_scan_start,
+ .change_queue_depth = sas_change_queue_depth,
+ .bios_param = sas_bios_param,
+ .can_queue = 1,
+ .this_id = -1,
+ .sg_tablesize = SG_ALL,
+ .max_sectors = SCSI_DEFAULT_MAX_SECTORS,
+ .use_clustering = ENABLE_CLUSTERING,
+ .eh_device_reset_handler = sas_eh_device_reset_handler,
+ .eh_target_reset_handler = sas_eh_target_reset_handler,
+ .target_destroy = sas_target_destroy,
+ .ioctl = sas_ioctl,
+ .shost_attrs = host_attrs,
+};
+
static const struct hisi_sas_hw hisi_sas_v1_hw = {
.hw_init = hisi_sas_v1_init,
.setup_itct = setup_itct_v1_hw,
@@ -1807,6 +1829,7 @@ static int hisi_sas_v1_init(struct hisi_hba *hisi_hba)
.get_wideport_bitmap = get_wideport_bitmap_v1_hw,
.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V1_HW,
.complete_hdr_size = sizeof(struct hisi_sas_complete_v1_hdr),
+ .sht = &sht_v1_hw,
};

static int hisi_sas_v1_probe(struct platform_device *pdev)
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
index fb0e966..8def327 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
@@ -3501,6 +3501,29 @@ static int write_gpio_v2_hw(struct hisi_hba *hisi_hba, u8 reg_type,
return 0;
}

+
+static struct scsi_host_template sht_v2_hw = {
+ .name = DRV_NAME,
+ .module = THIS_MODULE,
+ .queuecommand = sas_queuecommand,
+ .target_alloc = sas_target_alloc,
+ .slave_configure = hisi_sas_slave_configure,
+ .scan_finished = hisi_sas_scan_finished,
+ .scan_start = hisi_sas_scan_start,
+ .change_queue_depth = sas_change_queue_depth,
+ .bios_param = sas_bios_param,
+ .can_queue = 1,
+ .this_id = -1,
+ .sg_tablesize = SG_ALL,
+ .max_sectors = SCSI_DEFAULT_MAX_SECTORS,
+ .use_clustering = ENABLE_CLUSTERING,
+ .eh_device_reset_handler = sas_eh_device_reset_handler,
+ .eh_target_reset_handler = sas_eh_target_reset_handler,
+ .target_destroy = sas_target_destroy,
+ .ioctl = sas_ioctl,
+ .shost_attrs = host_attrs,
+};
+
static const struct hisi_sas_hw hisi_sas_v2_hw = {
.hw_init = hisi_sas_v2_init,
.setup_itct = setup_itct_v2_hw,
@@ -3529,6 +3552,7 @@ static int write_gpio_v2_hw(struct hisi_hba *hisi_hba, u8 reg_type,
.soft_reset = soft_reset_v2_hw,
.get_phys_state = get_phys_state_v2_hw,
.write_gpio = write_gpio_v2_hw,
+ .sht = &sht_v2_hw,
};

static int hisi_sas_v2_probe(struct platform_device *pdev)
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index a043d9c..13d2134 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -2015,6 +2015,28 @@ static int write_gpio_v3_hw(struct hisi_hba *hisi_hba, u8 reg_type,
return 0;
}

+static struct scsi_host_template sht_v3_hw = {
+ .name = DRV_NAME,
+ .module = THIS_MODULE,
+ .queuecommand = sas_queuecommand,
+ .target_alloc = sas_target_alloc,
+ .slave_configure = hisi_sas_slave_configure,
+ .scan_finished = hisi_sas_scan_finished,
+ .scan_start = hisi_sas_scan_start,
+ .change_queue_depth = sas_change_queue_depth,
+ .bios_param = sas_bios_param,
+ .can_queue = 1,
+ .this_id = -1,
+ .sg_tablesize = SG_ALL,
+ .max_sectors = SCSI_DEFAULT_MAX_SECTORS,
+ .use_clustering = ENABLE_CLUSTERING,
+ .eh_device_reset_handler = sas_eh_device_reset_handler,
+ .eh_target_reset_handler = sas_eh_target_reset_handler,
+ .target_destroy = sas_target_destroy,
+ .ioctl = sas_ioctl,
+ .shost_attrs = host_attrs,
+};
+
static const struct hisi_sas_hw hisi_sas_v3_hw = {
.hw_init = hisi_sas_v3_init,
.setup_itct = setup_itct_v3_hw,
@@ -2050,7 +2072,7 @@ static int write_gpio_v3_hw(struct hisi_hba *hisi_hba, u8 reg_type,
struct hisi_hba *hisi_hba;
struct device *dev = &pdev->dev;

- shost = scsi_host_alloc(hisi_sas_sht, sizeof(*hisi_hba));
+ shost = scsi_host_alloc(&sht_v3_hw, sizeof(*hisi_hba));
if (!shost) {
dev_err(dev, "shost alloc failed\n");
return NULL;
--
1.9.1