This new function is a variant of mf_generic_kill_procs that accepts a file, offset pair instead of a struct to support multiple files sharing a DAX mapping. It is intended to be called by the file systems as part of the memory_failure handler after the file system performed a reverse mapping from the storage address to the file and file offset. Signed-off-by: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx> Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> --- include/linux/mm.h | 2 + mm/memory-failure.c | 96 ++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 88 insertions(+), 10 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 8a96197b9afd..623c2ee8330a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3250,6 +3250,8 @@ enum mf_flags { MF_UNPOISON = 1 << 4, MF_NO_RETRY = 1 << 5, }; +int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, + unsigned long count, int mf_flags); extern int memory_failure(unsigned long pfn, int flags); extern void memory_failure_queue(unsigned long pfn, int flags); extern void memory_failure_queue_kick(int cpu); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index a9d93c30a1e4..5d015e1387bd 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -301,10 +301,9 @@ void shake_page(struct page *p) } EXPORT_SYMBOL_GPL(shake_page); -static unsigned long dev_pagemap_mapping_shift(struct page *page, - struct vm_area_struct *vma) +static unsigned long dev_pagemap_mapping_shift(struct vm_area_struct *vma, + unsigned long address) { - unsigned long address = vma_address(page, vma); unsigned long ret = 0; pgd_t *pgd; p4d_t *p4d; @@ -344,10 +343,14 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, /* * Schedule a process for later kill. * Uses GFP_ATOMIC allocations to avoid potential recursions in the VM. + * + * Notice: @fsdax_pgoff is used only when @p is a fsdax page. + * In other cases, such as anonymous and file-backend page, the address to be + * killed can be caculated by @p itself. */ static void add_to_kill(struct task_struct *tsk, struct page *p, - struct vm_area_struct *vma, - struct list_head *to_kill) + pgoff_t fsdax_pgoff, struct vm_area_struct *vma, + struct list_head *to_kill) { struct to_kill *tk; @@ -358,9 +361,15 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, } tk->addr = page_address_in_vma(p, vma); - if (is_zone_device_page(p)) - tk->size_shift = dev_pagemap_mapping_shift(p, vma); - else + if (is_zone_device_page(p)) { + /* + * Since page->mapping is not used for fsdax, we need + * calculate the address based on the vma. + */ + if (p->pgmap->type == MEMORY_DEVICE_FS_DAX) + tk->addr = vma_pgoff_address(fsdax_pgoff, 1, vma); + tk->size_shift = dev_pagemap_mapping_shift(vma, tk->addr); + } else tk->size_shift = page_shift(compound_head(p)); /* @@ -509,7 +518,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill, if (!page_mapped_in_vma(page, vma)) continue; if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + add_to_kill(t, page, 0, vma, to_kill); } } read_unlock(&tasklist_lock); @@ -545,13 +554,41 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill, * to be informed of all such data corruptions. */ if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + add_to_kill(t, page, 0, vma, to_kill); } } read_unlock(&tasklist_lock); i_mmap_unlock_read(mapping); } +#ifdef CONFIG_FS_DAX +/* + * Collect processes when the error hit a fsdax page. + */ +static void collect_procs_fsdax(struct page *page, + struct address_space *mapping, pgoff_t pgoff, + struct list_head *to_kill) +{ + struct vm_area_struct *vma; + struct task_struct *tsk; + + i_mmap_lock_read(mapping); + read_lock(&tasklist_lock); + for_each_process(tsk) { + struct task_struct *t = task_early_kill(tsk, true); + + if (!t) + continue; + vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { + if (vma->vm_mm == t->mm) + add_to_kill(t, page, pgoff, vma, to_kill); + } + } + read_unlock(&tasklist_lock); + i_mmap_unlock_read(mapping); +} +#endif /* CONFIG_FS_DAX */ + /* * Collect the processes who have the corrupted page mapped to kill. */ @@ -1591,6 +1628,45 @@ static int mf_generic_kill_procs(unsigned long long pfn, int flags, return rc; } +#ifdef CONFIG_FS_DAX +/** + * mf_dax_kill_procs - Collect and kill processes who are using this file range + * @mapping: address_space of the file in use + * @index: start pgoff of the range within the file + * @count: length of the range, in unit of PAGE_SIZE + * @mf_flags: memory failure flags + */ +int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, + unsigned long count, int mf_flags) +{ + LIST_HEAD(to_kill); + dax_entry_t cookie; + struct page *page; + size_t end = index + count; + + mf_flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; + + for (; index < end; index++) { + page = NULL; + cookie = dax_lock_mapping_entry(mapping, index, &page); + if (!cookie) + return -EBUSY; + if (!page) + goto unlock; + + SetPageHWPoison(page); + + collect_procs_fsdax(page, mapping, index, &to_kill); + unmap_and_kill(&to_kill, page_to_pfn(page), mapping, + index, mf_flags); +unlock: + dax_unlock_mapping_entry(mapping, index, cookie); + } + return 0; +} +EXPORT_SYMBOL_GPL(mf_dax_kill_procs); +#endif /* CONFIG_FS_DAX */ + /* * Called from hugetlb code with hugetlb_lock held. * -- 2.36.1