Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull HMM updates from Jason Gunthorpe:
 "Improvements and bug fixes for the hmm interface in the kernel:

   - Improve clarity, locking and APIs related to the 'hmm mirror'
     feature merged last cycle. In linux-next we now see AMDGPU and
     nouveau to be using this API.

   - Remove old or transitional hmm APIs. These are hold overs from the
     past with no users, or APIs that existed only to manage cross tree
     conflicts. There are still a few more of these cleanups that didn't
     make the merge window cut off.

   - Improve some core mm APIs:
       - export alloc_pages_vma() for driver use
       - refactor into devm_request_free_mem_region() to manage
         DEVICE_PRIVATE resource reservations
       - refactor duplicative driver code into the core dev_pagemap
         struct

   - Remove hmm wrappers of improved core mm APIs, instead have drivers
     use the simplified API directly

   - Remove DEVICE_PUBLIC

   - Simplify the kconfig flow for the hmm users and core code"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (42 commits)
  mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
  mm: remove the HMM config option
  mm: sort out the DEVICE_PRIVATE Kconfig mess
  mm: simplify ZONE_DEVICE page private data
  mm: remove hmm_devmem_add
  mm: remove hmm_vma_alloc_locked_page
  nouveau: use devm_memremap_pages directly
  nouveau: use alloc_page_vma directly
  PCI/P2PDMA: use the dev_pagemap internal refcount
  device-dax: use the dev_pagemap internal refcount
  memremap: provide an optional internal refcount in struct dev_pagemap
  memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
  memremap: remove the data field in struct dev_pagemap
  memremap: add a migrate_to_ram method to struct dev_pagemap_ops
  memremap: lift the devmap_enable manipulation into devm_memremap_pages
  memremap: pass a struct dev_pagemap to ->kill and ->cleanup
  memremap: move dev_pagemap callbacks into a separate structure
  memremap: validate the pagemap type passed to devm_memremap_pages
  mm: factor out a devm_request_free_mem_region helper
  mm: export alloc_pages_vma
  ...

1 files changed, 4 insertions, 48 deletions

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index a4994aa3acc0..a3073ce16520 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -25,12 +25,6 @@ struct pci_p2pdma {
 	bool p2pmem_published;
 };
 
-struct p2pdma_pagemap {
-	struct dev_pagemap pgmap;
-	struct percpu_ref ref;
-	struct completion ref_done;
-};
-
 static ssize_t size_show(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
@@ -79,31 +73,6 @@ static const struct attribute_group p2pmem_group = {
 	.name = "p2pmem",
 };
 
-static struct p2pdma_pagemap *to_p2p_pgmap(struct percpu_ref *ref)
-{
-	return container_of(ref, struct p2pdma_pagemap, ref);
-}
-
-static void pci_p2pdma_percpu_release(struct percpu_ref *ref)
-{
-	struct p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(ref);
-
-	complete(&p2p_pgmap->ref_done);
-}
-
-static void pci_p2pdma_percpu_kill(struct percpu_ref *ref)
-{
-	percpu_ref_kill(ref);
-}
-
-static void pci_p2pdma_percpu_cleanup(struct percpu_ref *ref)
-{
-	struct p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(ref);
-
-	wait_for_completion(&p2p_pgmap->ref_done);
-	percpu_ref_exit(&p2p_pgmap->ref);
-}
-
 static void pci_p2pdma_release(void *data)
 {
 	struct pci_dev *pdev = data;
@@ -166,7 +135,6 @@ out:
 int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
 			    u64 offset)
 {
-	struct p2pdma_pagemap *p2p_pgmap;
 	struct dev_pagemap *pgmap;
 	void *addr;
 	int error;
@@ -189,27 +157,15 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
 			return error;
 	}
 
-	p2p_pgmap = devm_kzalloc(&pdev->dev, sizeof(*p2p_pgmap), GFP_KERNEL);
-	if (!p2p_pgmap)
+	pgmap = devm_kzalloc(&pdev->dev, sizeof(*pgmap), GFP_KERNEL);
+	if (!pgmap)
 		return -ENOMEM;
-
-	init_completion(&p2p_pgmap->ref_done);
-	error = percpu_ref_init(&p2p_pgmap->ref,
-			pci_p2pdma_percpu_release, 0, GFP_KERNEL);
-	if (error)
-		goto pgmap_free;
-
-	pgmap = &p2p_pgmap->pgmap;
-
 	pgmap->res.start = pci_resource_start(pdev, bar) + offset;
 	pgmap->res.end = pgmap->res.start + size - 1;
 	pgmap->res.flags = pci_resource_flags(pdev, bar);
-	pgmap->ref = &p2p_pgmap->ref;
 	pgmap->type = MEMORY_DEVICE_PCI_P2PDMA;
 	pgmap->pci_p2pdma_bus_offset = pci_bus_address(pdev, bar) -
 		pci_resource_start(pdev, bar);
-	pgmap->kill = pci_p2pdma_percpu_kill;
-	pgmap->cleanup = pci_p2pdma_percpu_cleanup;
 
 	addr = devm_memremap_pages(&pdev->dev, pgmap);
 	if (IS_ERR(addr)) {
@@ -220,7 +176,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
 	error = gen_pool_add_owner(pdev->p2pdma->pool, (unsigned long)addr,
 			pci_bus_address(pdev, bar) + offset,
 			resource_size(&pgmap->res), dev_to_node(&pdev->dev),
-			&p2p_pgmap->ref);
+			pgmap->ref);
 	if (error)
 		goto pages_free;
 
@@ -232,7 +188,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
 pages_free:
 	devm_memunmap_pages(&pdev->dev, pgmap);
 pgmap_free:
-	devm_kfree(&pdev->dev, p2p_pgmap);
+	devm_kfree(&pdev->dev, pgmap);
 	return error;
 }
 EXPORT_SYMBOL_GPL(pci_p2pdma_add_resource);