[PATCH v6 09/11] PCI: endpoint: Fix EPF device name to support multi-function devices

From: Cyrille Pitchen
Date: Tue Jan 30 2018 - 15:59:58 EST


Fix the pci_epf_make() function so it can now bind many EPF devices to the
same EPF driver.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxxxxxxx>
---
drivers/pci/endpoint/pci-ep-cfs.c | 46 +++++++++++++++++++++++++++++++++++++--
1 file changed, 44 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 4f74386c1ced..48a89dff0e7f 100644
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -18,18 +18,22 @@
*/

#include <linux/module.h>
+#include <linux/idr.h>
#include <linux/slab.h>

#include <linux/pci-epc.h>
#include <linux/pci-epf.h>
#include <linux/pci-ep-cfs.h>

+static DEFINE_IDR(functions_idr);
+static DEFINE_MUTEX(functions_mutex);
static struct config_group *functions_group;
static struct config_group *controllers_group;

struct pci_epf_group {
struct config_group group;
struct pci_epf *epf;
+ int index;
};

struct pci_epc_group {
@@ -353,6 +357,9 @@ static void pci_epf_release(struct config_item *item)
{
struct pci_epf_group *epf_group = to_pci_epf_group(item);

+ mutex_lock(&functions_mutex);
+ idr_remove(&functions_idr, epf_group->index);
+ mutex_unlock(&functions_mutex);
pci_epf_destroy(epf_group->epf);
kfree(epf_group);
}
@@ -372,22 +379,57 @@ static struct config_group *pci_epf_make(struct config_group *group,
{
struct pci_epf_group *epf_group;
struct pci_epf *epf;
+ char *epf_name;
+ int index, err;

epf_group = kzalloc(sizeof(*epf_group), GFP_KERNEL);
if (!epf_group)
return ERR_PTR(-ENOMEM);

+ mutex_lock(&functions_mutex);
+ index = idr_alloc(&functions_idr, epf_group, 0, 0, GFP_KERNEL);
+ mutex_unlock(&functions_mutex);
+ if (index < 0) {
+ err = index;
+ goto free_group;
+ }
+
+ epf_group->index = index;
+
config_group_init_type_name(&epf_group->group, name, &pci_epf_type);

- epf = pci_epf_create(group->cg_item.ci_name);
+ epf_name = kasprintf(GFP_KERNEL, "%s.%d",
+ group->cg_item.ci_name, epf_group->index);
+ if (!epf_name) {
+ err = -ENOMEM;
+ goto remove_idr;
+ }
+
+ epf = pci_epf_create(epf_name);
if (IS_ERR(epf)) {
pr_err("failed to create endpoint function device\n");
- return ERR_PTR(-EINVAL);
+ err = -EINVAL;
+ goto free_name;
}

epf_group->epf = epf;

+ kfree(epf_name);
+
return &epf_group->group;
+
+free_name:
+ kfree(epf_name);
+
+remove_idr:
+ mutex_lock(&functions_mutex);
+ idr_remove(&functions_idr, epf_group->index);
+ mutex_unlock(&functions_mutex);
+
+free_group:
+ kfree(epf_group);
+
+ return ERR_PTR(err);
}

static void pci_epf_drop(struct config_group *group, struct config_item *item)
--
2.11.0