[PATCH v1 2/2] scsi: ufs: Modulize ufs-bsg

From: Can Guo
Date: Wed Dec 11 2019 - 03:29:09 EST


In order to improve the flexibility of ufs-bsg, modulizing it is a good
choice. This change introduces tristate to ufs-bsg to allow users compile
it as an external module.

Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/Kconfig | 3 ++-
drivers/scsi/ufs/Makefile | 2 +-
drivers/scsi/ufs/ufs_bsg.c | 49 +++++++++++++++++++++++++++++++++++++++++++---
drivers/scsi/ufs/ufs_bsg.h | 8 --------
drivers/scsi/ufs/ufshcd.c | 36 ++++++++++++++++++++++++++++++----
drivers/scsi/ufs/ufshcd.h | 7 ++++++-
6 files changed, 87 insertions(+), 18 deletions(-)

diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index d14c224..72620ce 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -38,6 +38,7 @@ config SCSI_UFSHCD
select PM_DEVFREQ
select DEVFREQ_GOV_SIMPLE_ONDEMAND
select NLS
+ select BLK_DEV_BSGLIB
---help---
This selects the support for UFS devices in Linux, say Y and make
sure that you know the name of your UFS host adapter (the card
@@ -143,7 +144,7 @@ config SCSI_UFS_TI_J721E
If unsure, say N.

config SCSI_UFS_BSG
- bool "Universal Flash Storage BSG device node"
+ tristate "Universal Flash Storage BSG device node"
depends on SCSI_UFSHCD
select BLK_DEV_BSGLIB
help
diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index 94c6c5d..904eff1 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -6,7 +6,7 @@ obj-$(CONFIG_SCSI_UFS_CDNS_PLATFORM) += cdns-pltfrm.o
obj-$(CONFIG_SCSI_UFS_QCOM) += ufs-qcom.o
obj-$(CONFIG_SCSI_UFSHCD) += ufshcd-core.o
ufshcd-core-y += ufshcd.o ufs-sysfs.o
-ufshcd-core-$(CONFIG_SCSI_UFS_BSG) += ufs_bsg.o
+obj-$(CONFIG_SCSI_UFS_BSG) += ufs_bsg.o
obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
obj-$(CONFIG_SCSI_UFS_HISI) += ufs-hisi.o
diff --git a/drivers/scsi/ufs/ufs_bsg.c b/drivers/scsi/ufs/ufs_bsg.c
index 3a2e68f..302222f 100644
--- a/drivers/scsi/ufs/ufs_bsg.c
+++ b/drivers/scsi/ufs/ufs_bsg.c
@@ -164,13 +164,15 @@ static int ufs_bsg_request(struct bsg_job *job)
*/
void ufs_bsg_remove(struct ufs_hba *hba)
{
- struct device *bsg_dev = &hba->bsg_dev;
+ struct device *bsg_dev = hba->bsg_dev;

if (!hba->bsg_queue)
return;

bsg_remove_queue(hba->bsg_queue);

+ hba->bsg_dev = NULL;
+ hba->bsg_queue = NULL;
device_del(bsg_dev);
put_device(bsg_dev);
}
@@ -178,6 +180,7 @@ void ufs_bsg_remove(struct ufs_hba *hba)
static inline void ufs_bsg_node_release(struct device *dev)
{
put_device(dev->parent);
+ kfree(dev);
}

/**
@@ -186,14 +189,19 @@ static inline void ufs_bsg_node_release(struct device *dev)
*
* Called during initial loading of the driver, and before scsi_scan_host.
*/
-int ufs_bsg_probe(struct ufs_hba *hba)
+static int ufs_bsg_probe(struct ufs_hba *hba)
{
- struct device *bsg_dev = &hba->bsg_dev;
+ struct device *bsg_dev;
struct Scsi_Host *shost = hba->host;
struct device *parent = &shost->shost_gendev;
struct request_queue *q;
int ret;

+ bsg_dev = kzalloc(sizeof(*bsg_dev), GFP_KERNEL);
+ if (!bsg_dev)
+ return -ENOMEM;
+
+ hba->bsg_dev = bsg_dev;
device_initialize(bsg_dev);

bsg_dev->parent = get_device(parent);
@@ -217,6 +225,41 @@ int ufs_bsg_probe(struct ufs_hba *hba)

out:
dev_err(bsg_dev, "fail to initialize a bsg dev %d\n", shost->host_no);
+ hba->bsg_dev = NULL;
put_device(bsg_dev);
return ret;
}
+
+static int __init ufs_bsg_init(void)
+{
+ struct list_head *hba_list = NULL;
+ struct ufs_hba *hba;
+ int ret = 0;
+
+ ufshcd_get_hba_list_lock(&hba_list);
+ list_for_each_entry(hba, hba_list, list) {
+ ret = ufs_bsg_probe(hba);
+ if (ret)
+ break;
+ }
+ ufshcd_put_hba_list_unlock();
+
+ return ret;
+}
+
+static void __exit ufs_bsg_exit(void)
+{
+ struct list_head *hba_list = NULL;
+ struct ufs_hba *hba;
+
+ ufshcd_get_hba_list_lock(&hba_list);
+ list_for_each_entry(hba, hba_list, list)
+ ufs_bsg_remove(hba);
+ ufshcd_put_hba_list_unlock();
+}
+
+late_initcall_sync(ufs_bsg_init);
+module_exit(ufs_bsg_exit);
+
+MODULE_ALIAS("ufs-bsg");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/scsi/ufs/ufs_bsg.h b/drivers/scsi/ufs/ufs_bsg.h
index d099187..9d922c0 100644
--- a/drivers/scsi/ufs/ufs_bsg.h
+++ b/drivers/scsi/ufs/ufs_bsg.h
@@ -12,12 +12,4 @@
#include "ufshcd.h"
#include "ufs.h"

-#ifdef CONFIG_SCSI_UFS_BSG
-void ufs_bsg_remove(struct ufs_hba *hba);
-int ufs_bsg_probe(struct ufs_hba *hba);
-#else
-static inline void ufs_bsg_remove(struct ufs_hba *hba) {}
-static inline int ufs_bsg_probe(struct ufs_hba *hba) {return 0; }
-#endif
-
#endif /* UFS_BSG_H */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a86b0fd..7a83a8f 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -108,6 +108,22 @@
16, 4, buf, __len, false); \
} while (0)

+static LIST_HEAD(ufs_hba_list);
+static DEFINE_MUTEX(ufs_hba_list_lock);
+
+void ufshcd_get_hba_list_lock(struct list_head **list)
+{
+ mutex_lock(&ufs_hba_list_lock);
+ *list = &ufs_hba_list;
+}
+EXPORT_SYMBOL_GPL(ufshcd_get_hba_list_lock);
+
+void ufshcd_put_hba_list_unlock(void)
+{
+ mutex_unlock(&ufs_hba_list_lock);
+}
+EXPORT_SYMBOL_GPL(ufshcd_put_hba_list_unlock);
+
int ufshcd_dump_regs(struct ufs_hba *hba, size_t offset, size_t len,
const char *prefix)
{
@@ -2093,6 +2109,7 @@ int ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd)
ufshcd_release(hba);
return ret;
}
+EXPORT_SYMBOL_GPL(ufshcd_send_uic_cmd);

/**
* ufshcd_map_sg - Map scatter-gather list to prdt
@@ -6024,6 +6041,7 @@ int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,

return err;
}
+EXPORT_SYMBOL_GPL(ufshcd_exec_raw_upiu_cmd);

/**
* ufshcd_eh_device_reset_handler - device reset handler registered to
@@ -7043,9 +7061,6 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
}
hba->clk_scaling.is_allowed = true;
}
-
- ufs_bsg_probe(hba);
-
scsi_scan_host(hba->host);
pm_runtime_put_sync(hba->dev);
}
@@ -8248,7 +8263,16 @@ int ufshcd_shutdown(struct ufs_hba *hba)
*/
void ufshcd_remove(struct ufs_hba *hba)
{
- ufs_bsg_remove(hba);
+ struct device *bsg_dev = hba->bsg_dev;
+
+ mutex_lock(&ufs_hba_list_lock);
+ list_del(&hba->list);
+ if (hba->bsg_queue) {
+ bsg_remove_queue(hba->bsg_queue);
+ device_del(bsg_dev);
+ put_device(bsg_dev);
+ }
+ mutex_unlock(&ufs_hba_list_lock);
ufs_sysfs_remove_nodes(hba->dev);
scsi_remove_host(hba->host);
scsi_host_put(hba->host);
@@ -8494,6 +8518,10 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
async_schedule(ufshcd_async_scan, hba);
ufs_sysfs_add_nodes(hba->dev);

+ mutex_lock(&ufs_hba_list_lock);
+ list_add_tail(&hba->list, &ufs_hba_list);
+ mutex_unlock(&ufs_hba_list_lock);
+
return 0;

out_remove_scsi_host:
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 2740f69..893debc 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -74,6 +74,9 @@

struct ufs_hba;

+void ufshcd_get_hba_list_lock(struct list_head **list);
+void ufshcd_put_hba_list_unlock(void);
+
enum dev_cmd_type {
DEV_CMD_TYPE_NOP = 0x0,
DEV_CMD_TYPE_QUERY = 0x1,
@@ -473,6 +476,7 @@ struct ufs_stats {

/**
* struct ufs_hba - per adapter private structure
+ * @list: Anchored at ufs_hba_list
* @mmio_base: UFSHCI base register address
* @ucdl_base_addr: UFS Command Descriptor base address
* @utrdl_base_addr: UTP Transfer Request Descriptor base address
@@ -527,6 +531,7 @@ struct ufs_stats {
* @scsi_block_reqs_cnt: reference counting for scsi block requests
*/
struct ufs_hba {
+ struct list_head list;
void __iomem *mmio_base;

/* Virtual memory reference */
@@ -734,7 +739,7 @@ struct ufs_hba {
struct ufs_desc_size desc_size;
atomic_t scsi_block_reqs_cnt;

- struct device bsg_dev;
+ struct device *bsg_dev;
struct request_queue *bsg_queue;
};

--
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