Re: [PATCH] dmaengine: idxd: add wq driver name support for accel-config user tool

From: Fenghua Yu
Date: Mon Oct 02 2023 - 16:25:25 EST

Next message: Mathieu Desnoyers: "[RFC PATCH v3 4/5] tracing/perf: add support for faultable tracepoints"
Previous message: Balas, Eliza: "RE: [PATCH v2 1/2] dt-bindings: misc: adi,axi-tdd: Add device-tree binding for TDD engine"
Next in thread: Vinod Koul: "Re: [PATCH] dmaengine: idxd: add wq driver name support for accel-config user tool"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hi, Vinod,

I see you applied a couple of IDXD patches to dmaengine tree last week. Really appreciate that!

This patch and another patch that fixes a split lock issue: https://lore.kernel.org/dmaengine/20230916060619.3744220-1-rex.zhang@xxxxxxxxx/ are not applied yet.

Any concern on these two patches? Are they good to be applied to dmaengine tree?

Thank you very much!

-Fenghua

On 9/8/23 13:10, Fenghua Yu wrote:

From: Dave Jiang <dave.jiang@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
Reviewed-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Acked-by: Vinod Koul <vkoul@xxxxxxxxxx>
---

Hi, Vinod,

This patch is part of IAA crypto patch series:
https://lore.kernel.org/all/20230731212939.1391453-2-tom.zanussi@xxxxxxxxxxxxxxx/
I'm sending this patch indepentantly here because:
1. the IAA crypto patch series is unlikely to be merged into 6.7
2. this patch is useful by itself in a few other places
3. this patch doesn't depend on the IAA crypto patch set and can
be used and applied cleanly by itself
4. this patch has only dmaengine code

So it would be good to merge this patch into 6.7 first. An updated
IAA crypto patch set will be submitted later after 6.7 time frame
and merged in a later kernel version.

.../ABI/stable/sysfs-driver-dma-idxd | 6 ++++
drivers/dma/idxd/cdev.c | 7 ++++
drivers/dma/idxd/dma.c | 6 ++++
drivers/dma/idxd/idxd.h | 9 +++++
drivers/dma/idxd/sysfs.c | 34 +++++++++++++++++++
include/uapi/linux/idxd.h | 1 +
6 files changed, 63 insertions(+)

diff --git a/Documentation/ABI/stable/sysfs-driver-dma-idxd b/Documentation/ABI/stable/sysfs-driver-dma-idxd
index 825e619250bf..982e9f3b80e2 100644
--- 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@xxxxxxxxxxxxxxx
+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 d32deb9b4e3d..0423655f5a88 100644
--- 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 07623fb0f52f..47a01893cfdb 100644
--- 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 e269ca1f4862..1e89c80a07fc 100644
--- 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 7caba90d85b3..523ae0dff7d4 100644
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1259,6 +1259,39 @@ static ssize_t wq_op_config_store(struct device *dev, struct device_attribute *a
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 606b52e88ce3..3d1987e1bb2d 100644
--- 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

Next message: Mathieu Desnoyers: "[RFC PATCH v3 4/5] tracing/perf: add support for faultable tracepoints"
Previous message: Balas, Eliza: "RE: [PATCH v2 1/2] dt-bindings: misc: adi,axi-tdd: Add device-tree binding for TDD engine"
Next in thread: Vinod Koul: "Re: [PATCH] dmaengine: idxd: add wq driver name support for accel-config user tool"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]