From 1e240e8d4a7d92232b6214e02a0a4197a53afd6c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:08 +0200 Subject: memremap: move dev_pagemap callbacks into a separate structure The dev_pagemap is a growing too many callbacks. Move them into a separate ops structure so that they are not duplicated for multiple instances, and an attacker can't easily overwrite them. Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/dax/device.c | 11 +++++++---- drivers/dax/pmem/core.c | 2 +- drivers/nvdimm/pmem.c | 19 +++++++++++-------- drivers/pci/p2pdma.c | 8 ++++++-- 4 files changed, 25 insertions(+), 15 deletions(-) (limited to 'drivers') diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 79014baa782d..f390083a64d7 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -36,9 +36,8 @@ static void dev_dax_percpu_exit(struct percpu_ref *ref) percpu_ref_exit(ref); } -static void dev_dax_percpu_kill(struct percpu_ref *data) +static void dev_dax_percpu_kill(struct percpu_ref *ref) { - struct percpu_ref *ref = data; struct dev_dax *dev_dax = ref_to_dev_dax(ref); dev_dbg(&dev_dax->dev, "%s\n", __func__); @@ -442,6 +441,11 @@ static void dev_dax_kill(void *dev_dax) kill_dev_dax(dev_dax); } +static const struct dev_pagemap_ops dev_dax_pagemap_ops = { + .kill = dev_dax_percpu_kill, + .cleanup = dev_dax_percpu_exit, +}; + int dev_dax_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); @@ -466,9 +470,8 @@ int dev_dax_probe(struct device *dev) return rc; dev_dax->pgmap.ref = &dev_dax->ref; - dev_dax->pgmap.kill = dev_dax_percpu_kill; - dev_dax->pgmap.cleanup = dev_dax_percpu_exit; dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; + dev_dax->pgmap.ops = &dev_dax_pagemap_ops; addr = devm_memremap_pages(dev, &dev_dax->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index f9f51786d556..6eb6dfdf19bf 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -16,7 +16,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) struct dev_dax *dev_dax; struct nd_namespace_io *nsio; struct dax_region *dax_region; - struct dev_pagemap pgmap = { 0 }; + struct dev_pagemap pgmap = { }; struct nd_namespace_common *ndns; struct nd_dax *nd_dax = to_nd_dax(dev); struct nd_pfn *nd_pfn = &nd_dax->nd_pfn; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 24d7fe7c74ed..c2449af2b388 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -303,7 +303,7 @@ static const struct attribute_group *pmem_attribute_groups[] = { NULL, }; -static void __pmem_release_queue(struct percpu_ref *ref) +static void pmem_pagemap_cleanup(struct percpu_ref *ref) { struct request_queue *q; @@ -313,10 +313,10 @@ static void __pmem_release_queue(struct percpu_ref *ref) static void pmem_release_queue(void *ref) { - __pmem_release_queue(ref); + pmem_pagemap_cleanup(ref); } -static void pmem_freeze_queue(struct percpu_ref *ref) +static void pmem_pagemap_kill(struct percpu_ref *ref) { struct request_queue *q; @@ -339,19 +339,24 @@ static void pmem_release_pgmap_ops(void *__pgmap) dev_pagemap_put_ops(); } -static void fsdax_pagefree(struct page *page, void *data) +static void pmem_pagemap_page_free(struct page *page, void *data) { wake_up_var(&page->_refcount); } +static const struct dev_pagemap_ops fsdax_pagemap_ops = { + .page_free = pmem_pagemap_page_free, + .kill = pmem_pagemap_kill, + .cleanup = pmem_pagemap_cleanup, +}; + static int setup_pagemap_fsdax(struct device *dev, struct dev_pagemap *pgmap) { dev_pagemap_get_ops(); if (devm_add_action_or_reset(dev, pmem_release_pgmap_ops, pgmap)) return -ENOMEM; pgmap->type = MEMORY_DEVICE_FS_DAX; - pgmap->page_free = fsdax_pagefree; - + pgmap->ops = &fsdax_pagemap_ops; return 0; } @@ -409,8 +414,6 @@ static int pmem_attach_disk(struct device *dev, pmem->pfn_flags = PFN_DEV; pmem->pgmap.ref = &q->q_usage_counter; - pmem->pgmap.kill = pmem_freeze_queue; - pmem->pgmap.cleanup = __pmem_release_queue; if (is_nd_pfn(dev)) { if (setup_pagemap_fsdax(dev, &pmem->pgmap)) return -ENOMEM; diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index a4994aa3acc0..fb039259d463 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -153,6 +153,11 @@ out: return error; } +static const struct dev_pagemap_ops pci_p2pdma_pagemap_ops = { + .kill = pci_p2pdma_percpu_kill, + .cleanup = pci_p2pdma_percpu_cleanup, +}; + /** * pci_p2pdma_add_resource - add memory for use as p2p memory * @pdev: the device to add the memory to @@ -208,8 +213,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, 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; + pgmap->ops = &pci_p2pdma_pagemap_ops; addr = devm_memremap_pages(&pdev->dev, pgmap); if (IS_ERR(addr)) { -- cgit v1.2.3-58-ga151