From a4574f63edc6f76fb46dcd65d3eb4d5a8e23ba38 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 13 Oct 2020 16:50:29 -0700 Subject: mm/memremap_pages: convert to 'struct range' MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The 'struct resource' in 'struct dev_pagemap' is only used for holding resource span information. The other fields, 'name', 'flags', 'desc', 'parent', 'sibling', and 'child' are all unused wasted space. This is in preparation for introducing a multi-range extension of devm_memremap_pages(). The bulk of this change is unwinding all the places internal to libnvdimm that used 'struct resource' unnecessarily, and replacing instances of 'struct dev_pagemap'.res with 'struct dev_pagemap'.range. P2PDMA had a minor usage of the resource flags field, but only to report failures with "%pR". That is replaced with an open coded print of the range. [dan.carpenter@oracle.com: mm/hmm/test: use after free in dmirror_allocate_chunk()] Link: https://lkml.kernel.org/r/20200926121402.GA7467@kadam Signed-off-by: Dan Williams Signed-off-by: Dan Carpenter Signed-off-by: Andrew Morton Reviewed-by: Boris Ostrovsky [xen] Cc: Paul Mackerras Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Vishal Verma Cc: Vivek Goyal Cc: Dave Jiang Cc: Ben Skeggs Cc: David Airlie Cc: Daniel Vetter Cc: Ira Weiny Cc: Bjorn Helgaas Cc: Juergen Gross Cc: Stefano Stabellini Cc: "Jérôme Glisse" Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Ard Biesheuvel Cc: Borislav Petkov Cc: Brice Goglin Cc: Catalin Marinas Cc: Dave Hansen Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Hulk Robot Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Jason Yan Cc: Jeff Moyer Cc: Jia He Cc: Joao Martins Cc: Jonathan Cameron Cc: kernel test robot Cc: Mike Rapoport Cc: Pavel Tatashin Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Randy Dunlap Cc: Thomas Gleixner Cc: Tom Lendacky Cc: Wei Yang Cc: Will Deacon Link: https://lkml.kernel.org/r/159643103173.4062302.768998885691711532.stgit@dwillia2-desk3.amr.corp.intel.com Link: https://lkml.kernel.org/r/160106115761.30709.13539840236873663620.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds --- lib/test_hmm.c | 50 +++++++++++++++++++++++++------------------------- 1 file changed, 25 insertions(+), 25 deletions(-) (limited to 'lib/test_hmm.c') diff --git a/lib/test_hmm.c b/lib/test_hmm.c index e7dc3de355b7..e97ca8ec0bce 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -460,6 +460,21 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, unsigned long pfn_last; void *ptr; + devmem = kzalloc(sizeof(*devmem), GFP_KERNEL); + if (!devmem) + return -ENOMEM; + + res = request_free_mem_region(&iomem_resource, DEVMEM_CHUNK_SIZE, + "hmm_dmirror"); + if (IS_ERR(res)) + goto err_devmem; + + devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; + devmem->pagemap.range.start = res->start; + devmem->pagemap.range.end = res->end; + devmem->pagemap.ops = &dmirror_devmem_ops; + devmem->pagemap.owner = mdevice; + mutex_lock(&mdevice->devmem_lock); if (mdevice->devmem_count == mdevice->devmem_capacity) { @@ -472,33 +487,18 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, sizeof(new_chunks[0]) * new_capacity, GFP_KERNEL); if (!new_chunks) - goto err; + goto err_release; mdevice->devmem_capacity = new_capacity; mdevice->devmem_chunks = new_chunks; } - res = request_free_mem_region(&iomem_resource, DEVMEM_CHUNK_SIZE, - "hmm_dmirror"); - if (IS_ERR(res)) - goto err; - - devmem = kzalloc(sizeof(*devmem), GFP_KERNEL); - if (!devmem) - goto err_release; - - devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; - devmem->pagemap.res = *res; - devmem->pagemap.ops = &dmirror_devmem_ops; - devmem->pagemap.owner = mdevice; - ptr = memremap_pages(&devmem->pagemap, numa_node_id()); if (IS_ERR(ptr)) - goto err_free; + goto err_release; devmem->mdevice = mdevice; - pfn_first = devmem->pagemap.res.start >> PAGE_SHIFT; - pfn_last = pfn_first + - (resource_size(&devmem->pagemap.res) >> PAGE_SHIFT); + pfn_first = devmem->pagemap.range.start >> PAGE_SHIFT; + pfn_last = pfn_first + (range_len(&devmem->pagemap.range) >> PAGE_SHIFT); mdevice->devmem_chunks[mdevice->devmem_count++] = devmem; mutex_unlock(&mdevice->devmem_lock); @@ -525,12 +525,12 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, return true; -err_free: - kfree(devmem); err_release: - release_mem_region(res->start, resource_size(res)); -err: mutex_unlock(&mdevice->devmem_lock); + release_mem_region(devmem->pagemap.range.start, range_len(&devmem->pagemap.range)); +err_devmem: + kfree(devmem); + return false; } @@ -1100,8 +1100,8 @@ static void dmirror_device_remove(struct dmirror_device *mdevice) mdevice->devmem_chunks[i]; memunmap_pages(&devmem->pagemap); - release_mem_region(devmem->pagemap.res.start, - resource_size(&devmem->pagemap.res)); + release_mem_region(devmem->pagemap.range.start, + range_len(&devmem->pagemap.range)); kfree(devmem); } kfree(mdevice->devmem_chunks); -- cgit From b7b3c01b191596d27a6980d1a42504f5b607f802 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 13 Oct 2020 16:50:34 -0700 Subject: mm/memremap_pages: support multiple ranges per invocation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In support of device-dax growing the ability to front physically dis-contiguous ranges of memory, update devm_memremap_pages() to track multiple ranges with a single reference counter and devm instance. Convert all [devm_]memremap_pages() users to specify the number of ranges they are mapping in their 'struct dev_pagemap' instance. Signed-off-by: Dan Williams Signed-off-by: Andrew Morton Cc: Paul Mackerras Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Vishal Verma Cc: Vivek Goyal Cc: Dave Jiang Cc: Ben Skeggs Cc: David Airlie Cc: Daniel Vetter Cc: Ira Weiny Cc: Bjorn Helgaas Cc: Boris Ostrovsky Cc: Juergen Gross Cc: Stefano Stabellini Cc: "Jérôme Glisse" Cc: Ard Biesheuvel Cc: Ard Biesheuvel Cc: Borislav Petkov Cc: Brice Goglin Cc: Catalin Marinas Cc: Dave Hansen Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Hulk Robot Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Jason Yan Cc: Jeff Moyer Cc: "Jérôme Glisse" Cc: Jia He Cc: Joao Martins Cc: Jonathan Cameron Cc: kernel test robot Cc: Mike Rapoport Cc: Pavel Tatashin Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Randy Dunlap Cc: Thomas Gleixner Cc: Tom Lendacky Cc: Wei Yang Cc: Will Deacon Link: https://lkml.kernel.org/r/159643103789.4062302.18426128170217903785.stgit@dwillia2-desk3.amr.corp.intel.com Link: https://lkml.kernel.org/r/160106116293.30709.13350662794915396198.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds --- lib/test_hmm.c | 1 + 1 file changed, 1 insertion(+) (limited to 'lib/test_hmm.c') diff --git a/lib/test_hmm.c b/lib/test_hmm.c index e97ca8ec0bce..c710b4c5714d 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -472,6 +472,7 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; devmem->pagemap.range.start = res->start; devmem->pagemap.range.end = res->end; + devmem->pagemap.nr_range = 1; devmem->pagemap.ops = &dmirror_devmem_ops; devmem->pagemap.owner = mdevice; -- cgit From 9b53122f616a74ddbbd6c97a3c8294c631a13d15 Mon Sep 17 00:00:00 2001 From: Ralph Campbell Date: Tue, 13 Oct 2020 16:54:32 -0700 Subject: lib/test_hmm.c: remove unused dmirror_zero_page The variable dmirror_zero_page is unused in the HMM self test driver which was probably intended to demonstrate how a driver could use migrate_vma_setup() to share a single read-only device private zero page similar to how the CPU does. However, this isn't needed for the self tests so remove it. Signed-off-by: Ralph Campbell Signed-off-by: Andrew Morton Cc: Jerome Glisse Link: https://lkml.kernel.org/r/20200914213801.16520-1-rcampbell@nvidia.com Signed-off-by: Linus Torvalds --- lib/test_hmm.c | 14 -------------- 1 file changed, 14 deletions(-) (limited to 'lib/test_hmm.c') diff --git a/lib/test_hmm.c b/lib/test_hmm.c index c710b4c5714d..e151a7f10519 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -36,7 +36,6 @@ static const struct dev_pagemap_ops dmirror_devmem_ops; static const struct mmu_interval_notifier_ops dmirror_min_ops; static dev_t dmirror_dev; -static struct page *dmirror_zero_page; struct dmirror_device; @@ -1127,17 +1126,6 @@ static int __init hmm_dmirror_init(void) goto err_chrdev; } - /* - * Allocate a zero page to simulate a reserved page of device private - * memory which is always zero. The zero_pfn page isn't used just to - * make the code here simpler (i.e., we need a struct page for it). - */ - dmirror_zero_page = alloc_page(GFP_HIGHUSER | __GFP_ZERO); - if (!dmirror_zero_page) { - ret = -ENOMEM; - goto err_chrdev; - } - pr_info("HMM test module loaded. This is only for testing HMM.\n"); return 0; @@ -1153,8 +1141,6 @@ static void __exit hmm_dmirror_exit(void) { int id; - if (dmirror_zero_page) - __free_page(dmirror_zero_page); for (id = 0; id < DMIRROR_NDEVICES; id++) dmirror_device_remove(dmirror_devices + id); unregister_chrdev_region(dmirror_dev, DMIRROR_NDEVICES); -- cgit From f3c9d0a3fe97a8b05548d27e9a8e7a5e6875004c Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 15 Oct 2020 20:11:34 -0700 Subject: lib/test_hmm.c: fix an error code in dmirror_allocate_chunk() This is supposed to return false on failure, not a negative error code. Fixes: 170e38548b81 ("mm/hmm/test: use after free in dmirror_allocate_chunk()") Signed-off-by: Dan Carpenter Signed-off-by: Andrew Morton Reviewed-by: Ralph Campbell Cc: Jerome Glisse Cc: Stephen Rothwell Cc: Jason Gunthorpe Cc: Dan Williams Link: https://lkml.kernel.org/r/20201010200812.GA1886610@mwanda Signed-off-by: Linus Torvalds --- lib/test_hmm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/test_hmm.c') diff --git a/lib/test_hmm.c b/lib/test_hmm.c index e151a7f10519..80a78877bd93 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -461,7 +461,7 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, devmem = kzalloc(sizeof(*devmem), GFP_KERNEL); if (!devmem) - return -ENOMEM; + return false; res = request_free_mem_region(&iomem_resource, DEVMEM_CHUNK_SIZE, "hmm_dmirror"); -- cgit