diff options
| -rw-r--r-- | drivers/platform/x86/amd/hsmp/acpi.c | 3 | ||||
| -rw-r--r-- | drivers/platform/x86/amd/hsmp/hsmp.c | 28 | ||||
| -rw-r--r-- | drivers/platform/x86/amd/hsmp/hsmp.h | 5 | ||||
| -rw-r--r-- | drivers/platform/x86/amd/hsmp/plat.c | 3 |
4 files changed, 39 insertions, 0 deletions
diff --git a/drivers/platform/x86/amd/hsmp/acpi.c b/drivers/platform/x86/amd/hsmp/acpi.c index a23797bd1dd5..a092d7589bcb 100644 --- a/drivers/platform/x86/amd/hsmp/acpi.c +++ b/drivers/platform/x86/amd/hsmp/acpi.c @@ -639,6 +639,8 @@ static int hsmp_acpi_probe(struct platform_device *pdev) GFP_KERNEL); if (!hsmp_pdev->sock) return -ENOMEM; + + hsmp_init_metric_read_locks(hsmp_pdev); } ret = init_acpi(&pdev->dev); @@ -670,6 +672,7 @@ static void hsmp_acpi_remove(struct platform_device *pdev) */ if (hsmp_pdev->is_probed) { hsmp_misc_deregister(); + hsmp_destroy_metric_read_locks(hsmp_pdev); hsmp_pdev->is_probed = false; } } diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c b/drivers/platform/x86/amd/hsmp/hsmp.c index 008f3c0b2ad7..fd36c8f142c0 100644 --- a/drivers/platform/x86/amd/hsmp/hsmp.c +++ b/drivers/platform/x86/amd/hsmp/hsmp.c @@ -10,9 +10,11 @@ #include <asm/amd/hsmp.h> #include <linux/acpi.h> +#include <linux/cleanup.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/io.h> +#include <linux/mutex.h> #include <linux/rwsem.h> #include <linux/semaphore.h> #include <linux/sysfs.h> @@ -415,6 +417,14 @@ ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size) msg.msg_id = HSMP_GET_METRIC_TABLE; msg.sock_ind = sock->sock_ind; + /* + * HSMP_GET_METRIC_TABLE makes firmware refill this socket's shared + * metric DRAM region, which is then copied out below. Hold the + * per-socket lock across the fill-and-copy so concurrent readers of the + * same socket cannot return a torn snapshot. + */ + guard(mutex)(&sock->metric_read_lock); + ret = hsmp_send_message(&msg); if (ret) return ret; @@ -424,6 +434,24 @@ ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size) } EXPORT_SYMBOL_NS_GPL(hsmp_metric_tbl_read, "AMD_HSMP"); +void hsmp_init_metric_read_locks(struct hsmp_plat_device *pdev) +{ + u16 i; + + for (i = 0; i < pdev->num_sockets; i++) + mutex_init(&pdev->sock[i].metric_read_lock); +} +EXPORT_SYMBOL_NS_GPL(hsmp_init_metric_read_locks, "AMD_HSMP"); + +void hsmp_destroy_metric_read_locks(struct hsmp_plat_device *pdev) +{ + u16 i; + + for (i = 0; i < pdev->num_sockets; i++) + mutex_destroy(&pdev->sock[i].metric_read_lock); +} +EXPORT_SYMBOL_NS_GPL(hsmp_destroy_metric_read_locks, "AMD_HSMP"); + void hsmp_unmap_metric_tbls(struct hsmp_plat_device *pdev) { struct hsmp_socket *sock; diff --git a/drivers/platform/x86/amd/hsmp/hsmp.h b/drivers/platform/x86/amd/hsmp/hsmp.h index b0d67b93363d..ec92c2a429bb 100644 --- a/drivers/platform/x86/amd/hsmp/hsmp.h +++ b/drivers/platform/x86/amd/hsmp/hsmp.h @@ -15,6 +15,7 @@ #include <linux/hwmon.h> #include <linux/kconfig.h> #include <linux/miscdevice.h> +#include <linux/mutex.h> #include <linux/pci.h> #include <linux/rwsem.h> #include <linux/semaphore.h> @@ -44,6 +45,8 @@ struct hsmp_socket { void __iomem *metric_tbl_addr; void __iomem *virt_base_addr; struct semaphore hsmp_sem; + /* Serializes HSMP_GET_METRIC_TABLE fill-and-copy for this socket */ + struct mutex metric_read_lock; char name[HSMP_ATTR_GRP_NAME_SIZE]; struct device *dev; u16 sock_ind; @@ -65,6 +68,8 @@ void hsmp_misc_deregister(void); int hsmp_misc_register(struct device *dev); int hsmp_get_tbl_dram_base(u16 sock_ind); void hsmp_unmap_metric_tbls(struct hsmp_plat_device *pdev); +void hsmp_init_metric_read_locks(struct hsmp_plat_device *pdev); +void hsmp_destroy_metric_read_locks(struct hsmp_plat_device *pdev); ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size); struct hsmp_plat_device *get_hsmp_pdev(void); #if IS_ENABLED(CONFIG_HWMON) diff --git a/drivers/platform/x86/amd/hsmp/plat.c b/drivers/platform/x86/amd/hsmp/plat.c index b5f2120765c8..7a16d1ab463b 100644 --- a/drivers/platform/x86/amd/hsmp/plat.c +++ b/drivers/platform/x86/amd/hsmp/plat.c @@ -212,6 +212,7 @@ static int init_platform_device(struct device *dev) static void hsmp_pltdrv_release(void *data) { hsmp_unmap_metric_tbls(hsmp_pdev); + hsmp_destroy_metric_read_locks(hsmp_pdev); } static int hsmp_pltdrv_probe(struct platform_device *pdev) @@ -224,6 +225,8 @@ static int hsmp_pltdrv_probe(struct platform_device *pdev) if (!hsmp_pdev->sock) return -ENOMEM; + hsmp_init_metric_read_locks(hsmp_pdev); + ret = devm_add_action_or_reset(&pdev->dev, hsmp_pltdrv_release, NULL); if (ret) return ret; |