| Message ID | 20181109203921.178363-2-brho@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] mm: make dev_pagemap_mapping_shift() externally visible | expand |
On 09.11.18 21:39, Barret Rhoden wrote: > KVM has a use case for determining the size of a dax mapping. The KVM > code has easy access to the address and the mm; hence the change in > parameters. > > Signed-off-by: Barret Rhoden <brho@google.com> > --- > include/linux/mm.h | 3 +++ > mm/memory-failure.c | 38 +++----------------------------------- > mm/util.c | 34 ++++++++++++++++++++++++++++++++++ > 3 files changed, 40 insertions(+), 35 deletions(-) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 5411de93a363..51215d695753 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -935,6 +935,9 @@ static inline bool is_pci_p2pdma_page(const struct page *page) > } > #endif /* CONFIG_DEV_PAGEMAP_OPS */ > > +unsigned long dev_pagemap_mapping_shift(unsigned long address, > + struct mm_struct *mm); > + > static inline void get_page(struct page *page) > { > page = compound_head(page); > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 0cd3de3550f0..c3f2c6a8607e 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -265,40 +265,6 @@ void shake_page(struct page *p, int access) > } > EXPORT_SYMBOL_GPL(shake_page); > > -static unsigned long dev_pagemap_mapping_shift(struct page *page, > - struct vm_area_struct *vma) > -{ > - unsigned long address = vma_address(page, vma); > - pgd_t *pgd; > - p4d_t *p4d; > - pud_t *pud; > - pmd_t *pmd; > - pte_t *pte; > - > - pgd = pgd_offset(vma->vm_mm, address); > - if (!pgd_present(*pgd)) > - return 0; > - p4d = p4d_offset(pgd, address); > - if (!p4d_present(*p4d)) > - return 0; > - pud = pud_offset(p4d, address); > - if (!pud_present(*pud)) > - return 0; > - if (pud_devmap(*pud)) > - return PUD_SHIFT; > - pmd = pmd_offset(pud, address); > - if (!pmd_present(*pmd)) > - return 0; > - if (pmd_devmap(*pmd)) > - return PMD_SHIFT; > - pte = pte_offset_map(pmd, address); > - if (!pte_present(*pte)) > - return 0; > - if (pte_devmap(*pte)) > - return PAGE_SHIFT; > - return 0; > -} > - > /* > * Failure handling: if we can't find or can't kill a process there's > * not much we can do. We just print a message and ignore otherwise. > @@ -329,7 +295,9 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, > tk->addr = page_address_in_vma(p, vma); > tk->addr_valid = 1; > if (is_zone_device_page(p)) > - tk->size_shift = dev_pagemap_mapping_shift(p, vma); > + tk->size_shift = > + dev_pagemap_mapping_shift(vma_address(page, vma), > + vma->vm_mm); > else > tk->size_shift = compound_order(compound_head(p)) + PAGE_SHIFT; > > diff --git a/mm/util.c b/mm/util.c > index 8bf08b5b5760..61bc9bab931d 100644 > --- a/mm/util.c > +++ b/mm/util.c > @@ -780,3 +780,37 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen) > out: > return res; > } > + > +unsigned long dev_pagemap_mapping_shift(unsigned long address, > + struct mm_struct *mm) > +{ > + pgd_t *pgd; > + p4d_t *p4d; > + pud_t *pud; > + pmd_t *pmd; > + pte_t *pte; > + > + pgd = pgd_offset(mm, address); > + if (!pgd_present(*pgd)) > + return 0; > + p4d = p4d_offset(pgd, address); > + if (!p4d_present(*p4d)) > + return 0; > + pud = pud_offset(p4d, address); > + if (!pud_present(*pud)) > + return 0; > + if (pud_devmap(*pud)) > + return PUD_SHIFT; > + pmd = pmd_offset(pud, address); > + if (!pmd_present(*pmd)) > + return 0; > + if (pmd_devmap(*pmd)) > + return PMD_SHIFT; > + pte = pte_offset_map(pmd, address); > + if (!pte_present(*pte)) > + return 0; > + if (pte_devmap(*pte)) > + return PAGE_SHIFT; > + return 0; > +} > +EXPORT_SYMBOL_GPL(dev_pagemap_mapping_shift); > Looks good to me Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/include/linux/mm.h b/include/linux/mm.h index 5411de93a363..51215d695753 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -935,6 +935,9 @@ static inline bool is_pci_p2pdma_page(const struct page *page) } #endif /* CONFIG_DEV_PAGEMAP_OPS */ +unsigned long dev_pagemap_mapping_shift(unsigned long address, + struct mm_struct *mm); + static inline void get_page(struct page *page) { page = compound_head(page); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 0cd3de3550f0..c3f2c6a8607e 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -265,40 +265,6 @@ void shake_page(struct page *p, int access) } EXPORT_SYMBOL_GPL(shake_page); -static unsigned long dev_pagemap_mapping_shift(struct page *page, - struct vm_area_struct *vma) -{ - unsigned long address = vma_address(page, vma); - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - pgd = pgd_offset(vma->vm_mm, address); - if (!pgd_present(*pgd)) - return 0; - p4d = p4d_offset(pgd, address); - if (!p4d_present(*p4d)) - return 0; - pud = pud_offset(p4d, address); - if (!pud_present(*pud)) - return 0; - if (pud_devmap(*pud)) - return PUD_SHIFT; - pmd = pmd_offset(pud, address); - if (!pmd_present(*pmd)) - return 0; - if (pmd_devmap(*pmd)) - return PMD_SHIFT; - pte = pte_offset_map(pmd, address); - if (!pte_present(*pte)) - return 0; - if (pte_devmap(*pte)) - return PAGE_SHIFT; - return 0; -} - /* * Failure handling: if we can't find or can't kill a process there's * not much we can do. We just print a message and ignore otherwise. @@ -329,7 +295,9 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, tk->addr = page_address_in_vma(p, vma); tk->addr_valid = 1; if (is_zone_device_page(p)) - tk->size_shift = dev_pagemap_mapping_shift(p, vma); + tk->size_shift = + dev_pagemap_mapping_shift(vma_address(page, vma), + vma->vm_mm); else tk->size_shift = compound_order(compound_head(p)) + PAGE_SHIFT; diff --git a/mm/util.c b/mm/util.c index 8bf08b5b5760..61bc9bab931d 100644 --- a/mm/util.c +++ b/mm/util.c @@ -780,3 +780,37 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen) out: return res; } + +unsigned long dev_pagemap_mapping_shift(unsigned long address, + struct mm_struct *mm) +{ + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + pgd = pgd_offset(mm, address); + if (!pgd_present(*pgd)) + return 0; + p4d = p4d_offset(pgd, address); + if (!p4d_present(*p4d)) + return 0; + pud = pud_offset(p4d, address); + if (!pud_present(*pud)) + return 0; + if (pud_devmap(*pud)) + return PUD_SHIFT; + pmd = pmd_offset(pud, address); + if (!pmd_present(*pmd)) + return 0; + if (pmd_devmap(*pmd)) + return PMD_SHIFT; + pte = pte_offset_map(pmd, address); + if (!pte_present(*pte)) + return 0; + if (pte_devmap(*pte)) + return PAGE_SHIFT; + return 0; +} +EXPORT_SYMBOL_GPL(dev_pagemap_mapping_shift);
KVM has a use case for determining the size of a dax mapping. The KVM code has easy access to the address and the mm; hence the change in parameters. Signed-off-by: Barret Rhoden <brho@google.com> --- include/linux/mm.h | 3 +++ mm/memory-failure.c | 38 +++----------------------------------- mm/util.c | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 40 insertions(+), 35 deletions(-)