On Wed, Jun 16, 2021 at 03:57:40PM -0700, Russ Weight wrote:
> The FPGA region class driver data structure is being treated as a
> managed resource instead of using standard dev_release call-back
> to release the class data structure. This change removes the
> managed resource code and combines the create() and register()
> functions into a single register() function.
>
> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> ---
> v5:
> - Rebased on top of recently accepted patches.
> - Created the fpga_region_ops data structure which is optionally passed
> to fpga_region_register(). compat_id, the get_bridges() pointer, and
> the priv pointer are included in the fpga_region_ops structure.
> v4:
> - Added the compat_id parameter to fpga_region_register() to ensure
> that the compat_id is set before the device_register() call.
> - Modified the dfl_fpga_feature_devs_enumerate() function to restore
> the fpga_region_register() call to the correct location.
> v3:
> - Cleaned up comment header for fpga_region_register()
> - Fix fpga_region_register() error return on ida_simple_get() failure
> v2:
> - No changes
> ---
> drivers/fpga/dfl-fme-pr.c | 2 +-
> drivers/fpga/dfl-fme-region.c | 32 ++++++---
> drivers/fpga/dfl.c | 12 ++--
> drivers/fpga/fpga-bridge.c | 2 +-
> drivers/fpga/fpga-region.c | 119 ++++++++-----------------------
> drivers/fpga/of-fpga-region.c | 14 ++--
> include/linux/fpga/fpga-region.h | 38 ++++++----
> 7 files changed, 86 insertions(+), 133 deletions(-)
>
> diff --git a/drivers/fpga/dfl-fme-pr.c b/drivers/fpga/dfl-fme-pr.c
> index d61ce9a18879..4805d8c533d4 100644
> --- a/drivers/fpga/dfl-fme-pr.c
> +++ b/drivers/fpga/dfl-fme-pr.c
> @@ -151,7 +151,7 @@ static int fme_pr(struct platform_device *pdev, unsigned long arg)
> * reenabling the bridge to clear things out between acceleration runs.
> * so no need to hold the bridges after partial reconfiguration.
> */
> - if (region->get_bridges)
> + if (region->rops && region->rops->get_bridges)
> fpga_bridges_put(®ion->bridge_list);
>
> put_device(®ion->dev);
> diff --git a/drivers/fpga/dfl-fme-region.c b/drivers/fpga/dfl-fme-region.c
> index a64c13e198a0..16d8b3f6f07a 100644
> --- a/drivers/fpga/dfl-fme-region.c
> +++ b/drivers/fpga/dfl-fme-region.c
> @@ -21,12 +21,29 @@
>
> static int fme_region_get_bridges(struct fpga_region *region)
> {
> - struct dfl_fme_region_pdata *pdata = region->priv;
> + struct dfl_fme_region_pdata *pdata = region->rops->priv;
> struct device *dev = &pdata->br->dev;
>
> return fpga_bridge_get_to_list(dev, region->info, ®ion->bridge_list);
> }
>
> +static struct fpga_region_ops *
> +fme_region_get_ops(struct device *dev, struct fpga_manager *mgr,
> + struct dfl_fme_region_pdata *pdata)
> +{
> + struct fpga_region_ops *ops;
> +
> + ops = devm_kzalloc(dev, sizeof(*ops), GFP_KERNEL);
> + if (!ops)
> + return NULL;
> +
> + ops->get_bridges = fme_region_get_bridges;
> + ops->compat_id = mgr->mops->compat_id;
> + ops->priv = pdata;
> +
> + return ops;
> +}
> +
> static int fme_region_probe(struct platform_device *pdev)
> {
> struct dfl_fme_region_pdata *pdata = dev_get_platdata(&pdev->dev);
> @@ -39,20 +56,15 @@ static int fme_region_probe(struct platform_device *pdev)
> if (IS_ERR(mgr))
> return -EPROBE_DEFER;
>
> - region = devm_fpga_region_create(dev, mgr, fme_region_get_bridges);
> - if (!region) {
> - ret = -ENOMEM;
> + region = fpga_region_register(dev, mgr,
> + fme_region_get_ops(dev, mgr, pdata));
> + if (IS_ERR(region)) {
> + ret = PTR_ERR(region);
> goto eprobe_mgr_put;
> }
>
> - region->priv = pdata;
> - region->compat_id = mgr->mops->compat_id;
> platform_set_drvdata(pdev, region);
>
> - ret = fpga_region_register(region);
> - if (ret)
> - goto eprobe_mgr_put;
> -
> dev_dbg(dev, "DFL FME FPGA Region probed\n");
>
> return 0;
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index 511b20ff35a3..3905995ef6d5 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -1400,19 +1400,15 @@ dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info)
> if (!cdev)
> return ERR_PTR(-ENOMEM);
>
> - cdev->region = devm_fpga_region_create(info->dev, NULL, NULL);
> - if (!cdev->region) {
> - ret = -ENOMEM;
> - goto free_cdev_exit;
> - }
> -
> cdev->parent = info->dev;
> mutex_init(&cdev->lock);
> INIT_LIST_HEAD(&cdev->port_dev_list);
>
> - ret = fpga_region_register(cdev->region);
> - if (ret)
> + cdev->region = fpga_region_register(info->dev, NULL, NULL);
> + if (IS_ERR(cdev->region)) {
> + ret = PTR_ERR(cdev->region);
> goto free_cdev_exit;
> + }
>
> /* create and init build info for enumeration */
> binfo = devm_kzalloc(info->dev, sizeof(*binfo), GFP_KERNEL);
> diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
> index 15be378b64ab..f7e8500561f4 100644
> --- a/drivers/fpga/fpga-bridge.c
> +++ b/drivers/fpga/fpga-bridge.c
> @@ -312,7 +312,7 @@ static struct attribute *fpga_bridge_attrs[] = {
> ATTRIBUTE_GROUPS(fpga_bridge);
>
> /**
> - * fpga_bridge_register - create and register a FPGA Bridge device
> + * fpga_bridge_register - create and register an FPGA Bridge device
> * @parent: FPGA bridge device from pdev
> * @name: FPGA bridge name
> * @br_ops: pointer to structure of fpga bridge ops
> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
> index a4838715221f..7199ad93814f 100644
> --- a/drivers/fpga/fpga-region.c
> +++ b/drivers/fpga/fpga-region.c
> @@ -115,8 +115,8 @@ int fpga_region_program_fpga(struct fpga_region *region)
> * In some cases, we already have a list of bridges in the
> * fpga region struct. Or we don't have any bridges.
> */
> - if (region->get_bridges) {
> - ret = region->get_bridges(region);
> + if (region->rops && region->rops->get_bridges) {
> + ret = region->rops->get_bridges(region);
> if (ret) {
> dev_err(dev, "failed to get fpga region bridges\n");
> goto err_unlock_mgr;
> @@ -147,7 +147,7 @@ int fpga_region_program_fpga(struct fpga_region *region)
> return 0;
>
> err_put_br:
> - if (region->get_bridges)
> + if (region->rops && region->rops->get_bridges)
> fpga_bridges_put(®ion->bridge_list);
> err_unlock_mgr:
> fpga_mgr_unlock(region->mgr);
> @@ -163,12 +163,12 @@ static ssize_t compat_id_show(struct device *dev,
> {
> struct fpga_region *region = to_fpga_region(dev);
>
> - if (!region->compat_id)
> + if (!region->rops || !region->rops->compat_id)
> return -ENOENT;
>
> return sprintf(buf, "%016llx%016llx\n",
> - (unsigned long long)region->compat_id->id_h,
> - (unsigned long long)region->compat_id->id_l);
> + (unsigned long long)region->rops->compat_id->id_h,
> + (unsigned long long)region->rops->compat_id->id_l);
> }
>
> static DEVICE_ATTR_RO(compat_id);
> @@ -180,39 +180,35 @@ static struct attribute *fpga_region_attrs[] = {
> ATTRIBUTE_GROUPS(fpga_region);
>
> /**
> - * fpga_region_create - alloc and init a struct fpga_region
> + * fpga_region_register - create and register an FPGA Region device
> * @parent: device parent
> * @mgr: manager that programs this region
> - * @get_bridges: optional function to get bridges to a list
> + * @rops: optional: FPGA Region ops for low level FPGA Region drivers
> *
> - * The caller of this function is responsible for freeing the resulting region
> - * struct with fpga_region_free(). Using devm_fpga_region_create() instead is
> - * recommended.
> - *
> - * Return: struct fpga_region or NULL
> + * Return: struct fpga_region or ERR_PTR()
> */
> -struct fpga_region
> -*fpga_region_create(struct device *parent,
> - struct fpga_manager *mgr,
> - int (*get_bridges)(struct fpga_region *))
> +struct fpga_region *
> +fpga_region_register(struct device *parent, struct fpga_manager *mgr,
> + struct fpga_region_ops *rops)
Is it better we use the same style as fpga_mgr_register?
Thanks,
Yilun
> {
> struct fpga_region *region;
> int id, ret = 0;
>
> region = kzalloc(sizeof(*region), GFP_KERNEL);
> if (!region)
> - return NULL;
> + return ERR_PTR(-ENOMEM);
>
> id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
> - if (id < 0)
> + if (id < 0) {
> + ret = id;
> goto err_free;
> + }
>
> region->mgr = mgr;
> - region->get_bridges = get_bridges;
> + region->rops = rops;
> mutex_init(®ion->mutex);
> INIT_LIST_HEAD(®ion->bridge_list);
>
> - device_initialize(®ion->dev);
> region->dev.class = fpga_region_class;
> region->dev.parent = parent;
> region->dev.of_node = parent->of_node;
> @@ -222,6 +218,12 @@ struct fpga_region
> if (ret)
> goto err_remove;
>
> + ret = device_register(®ion->dev);
> + if (ret) {
> + put_device(®ion->dev);
> + return ERR_PTR(ret);
> + }
> +
> return region;
>
> err_remove:
> @@ -229,76 +231,7 @@ struct fpga_region
> err_free:
> kfree(region);
>
> - return NULL;
> -}
> -EXPORT_SYMBOL_GPL(fpga_region_create);
> -
> -/**
> - * fpga_region_free - free an FPGA region created by fpga_region_create()
> - * @region: FPGA region
> - */
> -void fpga_region_free(struct fpga_region *region)
> -{
> - ida_simple_remove(&fpga_region_ida, region->dev.id);
> - kfree(region);
> -}
> -EXPORT_SYMBOL_GPL(fpga_region_free);
> -
> -static void devm_fpga_region_release(struct device *dev, void *res)
> -{
> - struct fpga_region *region = *(struct fpga_region **)res;
> -
> - fpga_region_free(region);
> -}
> -
> -/**
> - * devm_fpga_region_create - create and initialize a managed FPGA region struct
> - * @parent: device parent
> - * @mgr: manager that programs this region
> - * @get_bridges: optional function to get bridges to a list
> - *
> - * This function is intended for use in an FPGA region driver's probe function.
> - * After the region driver creates the region struct with
> - * devm_fpga_region_create(), it should register it with fpga_region_register().
> - * The region driver's remove function should call fpga_region_unregister().
> - * The region struct allocated with this function will be freed automatically on
> - * driver detach. This includes the case of a probe function returning error
> - * before calling fpga_region_register(), the struct will still get cleaned up.
> - *
> - * Return: struct fpga_region or NULL
> - */
> -struct fpga_region
> -*devm_fpga_region_create(struct device *parent,
> - struct fpga_manager *mgr,
> - int (*get_bridges)(struct fpga_region *))
> -{
> - struct fpga_region **ptr, *region;
> -
> - ptr = devres_alloc(devm_fpga_region_release, sizeof(*ptr), GFP_KERNEL);
> - if (!ptr)
> - return NULL;
> -
> - region = fpga_region_create(parent, mgr, get_bridges);
> - if (!region) {
> - devres_free(ptr);
> - } else {
> - *ptr = region;
> - devres_add(parent, ptr);
> - }
> -
> - return region;
> -}
> -EXPORT_SYMBOL_GPL(devm_fpga_region_create);
> -
> -/**
> - * fpga_region_register - register an FPGA region
> - * @region: FPGA region
> - *
> - * Return: 0 or -errno
> - */
> -int fpga_region_register(struct fpga_region *region)
> -{
> - return device_add(®ion->dev);
> + return ERR_PTR(ret);
> }
> EXPORT_SYMBOL_GPL(fpga_region_register);
>
> @@ -316,6 +249,10 @@ EXPORT_SYMBOL_GPL(fpga_region_unregister);
>
> static void fpga_region_dev_release(struct device *dev)
> {
> + struct fpga_region *region = to_fpga_region(dev);
> +
> + ida_simple_remove(&fpga_region_ida, region->dev.id);
> + kfree(region);
> }
>
> /**
> diff --git a/drivers/fpga/of-fpga-region.c b/drivers/fpga/of-fpga-region.c
> index e3c25576b6b9..55b7c4ec8f6d 100644
> --- a/drivers/fpga/of-fpga-region.c
> +++ b/drivers/fpga/of-fpga-region.c
> @@ -392,6 +392,10 @@ static struct notifier_block fpga_region_of_nb = {
> .notifier_call = of_fpga_region_notify,
> };
>
> +static struct fpga_region_ops of_fpga_region_ops = {
> + .get_bridges = of_fpga_region_get_bridges;
> +};
> +
> static int of_fpga_region_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> @@ -405,16 +409,12 @@ static int of_fpga_region_probe(struct platform_device *pdev)
> if (IS_ERR(mgr))
> return -EPROBE_DEFER;
>
> - region = devm_fpga_region_create(dev, mgr, of_fpga_region_get_bridges);
> - if (!region) {
> - ret = -ENOMEM;
> + region = fpga_region_register(dev, mgr, &of_fpga_region_ops);
> + if (IS_ERR(region)) {
> + ret = PTR_ERR(region);
> goto eprobe_mgr_put;
> }
>
> - ret = fpga_region_register(region);
> - if (ret)
> - goto eprobe_mgr_put;
> -
> of_platform_populate(np, fpga_region_of_match, NULL, ®ion->dev);
> platform_set_drvdata(pdev, region);
>
> diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
> index 27cb706275db..02626dfd41ed 100644
> --- a/include/linux/fpga/fpga-region.h
> +++ b/include/linux/fpga/fpga-region.h
> @@ -7,6 +7,24 @@
> #include <linux/fpga/fpga-mgr.h>
> #include <linux/fpga/fpga-bridge.h>
>
> +struct fpga_region;
> +
> +/**
> + * struct fpga_region_ops - ops for low level fpga region drivers
> + * @get_bridges: optional function to get bridges to a list
> + * @compat_id: optional: FPGA manager id for compatibility check.
> + * @priv: optional: private data
> + *
> + * fpga_region_ops are the low level functions implemented by a specific
> + * fpga region driver. The optional ones are tested for NULL before being
> + * referenced, so leaving them out is fine.
> + */
> +struct fpga_region_ops {
> + int (*get_bridges)(struct fpga_region *region);
> + struct fpga_compat_id *compat_id;
> + void *priv;
> +};
> +
> /**
> * struct fpga_region - FPGA Region structure
> * @dev: FPGA Region device
> @@ -14,9 +32,7 @@
> * @bridge_list: list of FPGA bridges specified in region
> * @mgr: FPGA manager
> * @info: FPGA image info
> - * @compat_id: FPGA region id for compatibility check.
> - * @priv: private data
> - * @get_bridges: optional function to get bridges to a list
> + * @rops: optional: FPGA Region ops for low level FPGA region drivers
> */
> struct fpga_region {
> struct device dev;
> @@ -24,9 +40,7 @@ struct fpga_region {
> struct list_head bridge_list;
> struct fpga_manager *mgr;
> struct fpga_image_info *info;
> - struct fpga_compat_id *compat_id;
> - void *priv;
> - int (*get_bridges)(struct fpga_region *region);
> + struct fpga_region_ops *rops;
> };
>
> #define to_fpga_region(d) container_of(d, struct fpga_region, dev)
> @@ -37,15 +51,9 @@ struct fpga_region *fpga_region_class_find(
>
> int fpga_region_program_fpga(struct fpga_region *region);
>
> -struct fpga_region
> -*fpga_region_create(struct device *dev, struct fpga_manager *mgr,
> - int (*get_bridges)(struct fpga_region *));
> -void fpga_region_free(struct fpga_region *region);
> -int fpga_region_register(struct fpga_region *region);
> +struct fpga_region *
> +fpga_region_register(struct device *dev, struct fpga_manager *mgr,
> + struct fpga_region_ops *rops);
> void fpga_region_unregister(struct fpga_region *region);
>
> -struct fpga_region
> -*devm_fpga_region_create(struct device *dev, struct fpga_manager *mgr,
> - int (*get_bridges)(struct fpga_region *));
> -
> #endif /* _FPGA_REGION_H */
> --
> 2.25.1
