dmaengine: idxd: add wq driver name support for accel-config user tool

With the possibility of multiple wq drivers that can be bound to the wq,
the user config tool accel-config needs a way to know which wq driver to
bind to the wq. Introduce per wq driver_name sysfs attribute where the user
can indicate the driver to be bound to the wq. This allows accel-config to
just bind to the driver using wq->driver_name.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20230908201045.4115614-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/Documentation/ABI/stable/sysfs-driver-dma-idxd b/Documentation/ABI/stable/sysfs-driver-dma-idxd
index 825e619250bf2ebb77d6c2abc9843414c8b5efd5..f2ec42949a54d7b293541810fec83c7cfa8e26a3 100644 (file)
--- a/Documentation/ABI/stable/sysfs-driver-dma-idxd
+++ b/Documentation/ABI/stable/sysfs-driver-dma-idxd
@@ -270,6 +270,12 @@ Description:       Shows the operation capability bits displayed in bitmap format
                correlates to the operations allowed. It's visible only
                on platforms that support the capability.
 
+What:          /sys/bus/dsa/devices/wq<m>.<n>/driver_name
+Date:          Sept 8, 2023
+KernelVersion: 6.7.0
+Contact:       dmaengine@vger.kernel.org
+Description:   Name of driver to be bounded to the wq.
+
 What:           /sys/bus/dsa/devices/engine<m>.<n>/group_id
 Date:           Oct 25, 2019
 KernelVersion:  5.6.0

diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c
index d32deb9b4e3dee466fd056230596aa42198d8285..0423655f5a88045e2f02119f2bd112f203b011a3 100644 (file)
--- a/drivers/dma/idxd/cdev.c
+++ b/drivers/dma/idxd/cdev.c
@@ -509,6 +509,7 @@ void idxd_wq_del_cdev(struct idxd_wq *wq)
 
 static int idxd_user_drv_probe(struct idxd_dev *idxd_dev)
 {
+       struct device *dev = &idxd_dev->conf_dev;
        struct idxd_wq *wq = idxd_dev_to_wq(idxd_dev);
        struct idxd_device *idxd = wq->idxd;
        int rc;
@@ -536,6 +537,12 @@ static int idxd_user_drv_probe(struct idxd_dev *idxd_dev)
 
        mutex_lock(&wq->wq_lock);
 
+       if (!idxd_wq_driver_name_match(wq, dev)) {
+               idxd->cmd_status = IDXD_SCMD_WQ_NO_DRV_NAME;
+               rc = -ENODEV;
+               goto wq_err;
+       }
+
        wq->wq = create_workqueue(dev_name(wq_confdev(wq)));
        if (!wq->wq) {
                rc = -ENOMEM;

diff --git a/drivers/dma/idxd/dma.c b/drivers/dma/idxd/dma.c
index 07623fb0f52fc2bb160224ecf5d0dc0e625e2b00..47a01893cfdbf9667ae62d9cbe934350135b8285 100644 (file)
--- a/drivers/dma/idxd/dma.c
+++ b/drivers/dma/idxd/dma.c
@@ -306,6 +306,12 @@ static int idxd_dmaengine_drv_probe(struct idxd_dev *idxd_dev)
                return -ENXIO;
 
        mutex_lock(&wq->wq_lock);
+       if (!idxd_wq_driver_name_match(wq, dev)) {
+               idxd->cmd_status = IDXD_SCMD_WQ_NO_DRV_NAME;
+               rc = -ENODEV;
+               goto err;
+       }
+
        wq->type = IDXD_WQT_KERNEL;
 
        rc = drv_enable_wq(wq);

diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h
index e269ca1f48625513fb03df0f678919db5ccc3c48..1e89c80a07fc25f2ba9dee61743ccd12cc483052 100644 (file)
--- a/drivers/dma/idxd/idxd.h
+++ b/drivers/dma/idxd/idxd.h
@@ -159,6 +159,8 @@ struct idxd_cdev {
        int minor;
 };
 
+#define DRIVER_NAME_SIZE               128
+
 #define IDXD_ALLOCATED_BATCH_SIZE      128U
 #define WQ_NAME_SIZE   1024
 #define WQ_TYPE_SIZE   10
@@ -227,6 +229,8 @@ struct idxd_wq {
        /* Lock to protect upasid_xa access. */
        struct mutex uc_lock;
        struct xarray upasid_xa;
+
+       char driver_name[DRIVER_NAME_SIZE + 1];
 };
 
 struct idxd_engine {
@@ -646,6 +650,11 @@ static inline void idxd_wqcfg_set_max_batch_shift(int idxd_type, union wqcfg *wq
                wqcfg->max_batch_shift = max_batch_shift;
 }
 
+static inline int idxd_wq_driver_name_match(struct idxd_wq *wq, struct device *dev)
+{
+       return (strncmp(wq->driver_name, dev->driver->name, strlen(dev->driver->name)) == 0);
+}
+
 int __must_check __idxd_driver_register(struct idxd_device_driver *idxd_drv,
                                        struct module *module, const char *mod_name);
 #define idxd_driver_register(driver) \

diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index 7caba90d85b31e2d2519e7ff564f2c106e51ccc2..523ae0dff7d4aaafe80998b65de1eddecc4fcd76 100644 (file)
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1259,6 +1259,39 @@ err:
 static struct device_attribute dev_attr_wq_op_config =
                __ATTR(op_config, 0644, wq_op_config_show, wq_op_config_store);
 
+static ssize_t wq_driver_name_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct idxd_wq *wq = confdev_to_wq(dev);
+
+       return sysfs_emit(buf, "%s\n", wq->driver_name);
+}
+
+static ssize_t wq_driver_name_store(struct device *dev, struct device_attribute *attr,
+                                   const char *buf, size_t count)
+{
+       struct idxd_wq *wq = confdev_to_wq(dev);
+       char *input, *pos;
+
+       if (wq->state != IDXD_WQ_DISABLED)
+               return -EPERM;
+
+       if (strlen(buf) > DRIVER_NAME_SIZE || strlen(buf) == 0)
+               return -EINVAL;
+
+       input = kstrndup(buf, count, GFP_KERNEL);
+       if (!input)
+               return -ENOMEM;
+
+       pos = strim(input);
+       memset(wq->driver_name, 0, DRIVER_NAME_SIZE + 1);
+       sprintf(wq->driver_name, "%s", pos);
+       kfree(input);
+       return count;
+}
+
+static struct device_attribute dev_attr_wq_driver_name =
+               __ATTR(driver_name, 0644, wq_driver_name_show, wq_driver_name_store);
+
 static struct attribute *idxd_wq_attributes[] = {
        &dev_attr_wq_clients.attr,
        &dev_attr_wq_state.attr,
@@ -1278,6 +1311,7 @@ static struct attribute *idxd_wq_attributes[] = {
        &dev_attr_wq_occupancy.attr,
        &dev_attr_wq_enqcmds_retries.attr,
        &dev_attr_wq_op_config.attr,
+       &dev_attr_wq_driver_name.attr,
        NULL,
 };
 

diff --git a/include/uapi/linux/idxd.h b/include/uapi/linux/idxd.h
index 606b52e88ce335b02e3efa5a558fd3bba20481ab..3d1987e1bb2dd65557d11c2fe99c89c2d9b1704c 100644 (file)
--- a/include/uapi/linux/idxd.h
+++ b/include/uapi/linux/idxd.h
@@ -31,6 +31,7 @@ enum idxd_scmd_stat {
        IDXD_SCMD_WQ_IRQ_ERR = 0x80100000,
        IDXD_SCMD_WQ_USER_NO_IOMMU = 0x80110000,
        IDXD_SCMD_DEV_EVL_ERR = 0x80120000,
+       IDXD_SCMD_WQ_NO_DRV_NAME = 0x80200000,
 };
 
 #define IDXD_SCMD_SOFTERR_MASK 0x80000000