diff options
author | Shiyang Ruan <ruansy.fnst@fujitsu.com> | 2022-06-03 08:37:26 +0300 |
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committer | akpm <akpm@linux-foundation.org> | 2022-07-18 03:14:30 +0300 |
commit | 00cc790e00369387f6ab80c5724550c2c6340334 (patch) | |
tree | 5c1b5958aabb7562cd21974ca1cc5477a627a6fc /mm | |
parent | 8012b866085523758780850087102421dbcce522 (diff) | |
download | linux-00cc790e00369387f6ab80c5724550c2c6340334.tar.xz |
mm: factor helpers for memory_failure_dev_pagemap
memory_failure_dev_pagemap code is a bit complex before introduce RMAP
feature for fsdax. So it is needed to factor some helper functions to
simplify these code.
[akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n build]
[zhengbin13@huawei.com: fix redefinition of mf_generic_kill_procs]
Link: https://lkml.kernel.org/r/20220628112143.1170473-1-zhengbin13@huawei.com
Link: https://lkml.kernel.org/r/20220603053738.1218681-3-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.wiliams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/memory-failure.c | 171 |
1 files changed, 95 insertions, 76 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b7ca5db7e60e..f8a8a5d45eba 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1499,6 +1499,95 @@ static int try_to_split_thp_page(struct page *page, const char *msg) return 0; } +static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, + struct address_space *mapping, pgoff_t index, int flags) +{ + struct to_kill *tk; + unsigned long size = 0; + + list_for_each_entry(tk, to_kill, nd) + if (tk->size_shift) + size = max(size, 1UL << tk->size_shift); + + if (size) { + /* + * Unmap the largest mapping to avoid breaking up device-dax + * mappings which are constant size. The actual size of the + * mapping being torn down is communicated in siginfo, see + * kill_proc() + */ + loff_t start = (index << PAGE_SHIFT) & ~(size - 1); + + unmap_mapping_range(mapping, start, size, 0); + } + + kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); +} + +static int mf_generic_kill_procs(unsigned long long pfn, int flags, + struct dev_pagemap *pgmap) +{ + struct page *page = pfn_to_page(pfn); + LIST_HEAD(to_kill); + dax_entry_t cookie; + int rc = 0; + + /* + * Pages instantiated by device-dax (not filesystem-dax) + * may be compound pages. + */ + page = compound_head(page); + + /* + * Prevent the inode from being freed while we are interrogating + * the address_space, typically this would be handled by + * lock_page(), but dax pages do not use the page lock. This + * also prevents changes to the mapping of this pfn until + * poison signaling is complete. + */ + cookie = dax_lock_page(page); + if (!cookie) + return -EBUSY; + + if (hwpoison_filter(page)) { + rc = -EOPNOTSUPP; + goto unlock; + } + + switch (pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + case MEMORY_DEVICE_COHERENT: + /* + * TODO: Handle device pages which may need coordination + * with device-side memory. + */ + rc = -ENXIO; + goto unlock; + default: + break; + } + + /* + * Use this flag as an indication that the dax page has been + * remapped UC to prevent speculative consumption of poison. + */ + SetPageHWPoison(page); + + /* + * Unlike System-RAM there is no possibility to swap in a + * different physical page at a given virtual address, so all + * userspace consumption of ZONE_DEVICE memory necessitates + * SIGBUS (i.e. MF_MUST_KILL) + */ + flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; + collect_procs(page, &to_kill, true); + + unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); +unlock: + dax_unlock_page(page, cookie); + return rc; +} + /* * Called from hugetlb code with hugetlb_lock held. * @@ -1634,23 +1723,20 @@ out: unlock_page(head); return res; } + #else static inline int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb) { return 0; } -#endif + +#endif /* CONFIG_HUGETLB_PAGE */ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, struct dev_pagemap *pgmap) { struct page *page = pfn_to_page(pfn); - unsigned long size = 0; - struct to_kill *tk; - LIST_HEAD(tokill); - int rc = -EBUSY; - loff_t start; - dax_entry_t cookie; + int rc = -ENXIO; if (flags & MF_COUNT_INCREASED) /* @@ -1659,77 +1745,10 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, put_page(page); /* device metadata space is not recoverable */ - if (!pgmap_pfn_valid(pgmap, pfn)) { - rc = -ENXIO; + if (!pgmap_pfn_valid(pgmap, pfn)) goto out; - } - - /* - * Pages instantiated by device-dax (not filesystem-dax) - * may be compound pages. - */ - page = compound_head(page); - - /* - * Prevent the inode from being freed while we are interrogating - * the address_space, typically this would be handled by - * lock_page(), but dax pages do not use the page lock. This - * also prevents changes to the mapping of this pfn until - * poison signaling is complete. - */ - cookie = dax_lock_page(page); - if (!cookie) - goto out; - - if (hwpoison_filter(page)) { - rc = -EOPNOTSUPP; - goto unlock; - } - - switch (pgmap->type) { - case MEMORY_DEVICE_PRIVATE: - case MEMORY_DEVICE_COHERENT: - /* - * TODO: Handle device pages which may need coordination - * with device-side memory. - */ - goto unlock; - default: - break; - } - /* - * Use this flag as an indication that the dax page has been - * remapped UC to prevent speculative consumption of poison. - */ - SetPageHWPoison(page); - - /* - * Unlike System-RAM there is no possibility to swap in a - * different physical page at a given virtual address, so all - * userspace consumption of ZONE_DEVICE memory necessitates - * SIGBUS (i.e. MF_MUST_KILL) - */ - flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; - collect_procs(page, &tokill, true); - - list_for_each_entry(tk, &tokill, nd) - if (tk->size_shift) - size = max(size, 1UL << tk->size_shift); - if (size) { - /* - * Unmap the largest mapping to avoid breaking up - * device-dax mappings which are constant size. The - * actual size of the mapping being torn down is - * communicated in siginfo, see kill_proc() - */ - start = (page->index << PAGE_SHIFT) & ~(size - 1); - unmap_mapping_range(page->mapping, start, size, 0); - } - kill_procs(&tokill, true, false, pfn, flags); - rc = 0; -unlock: - dax_unlock_page(page, cookie); + rc = mf_generic_kill_procs(pfn, flags, pgmap); out: /* drop pgmap ref acquired in caller */ put_dev_pagemap(pgmap); |