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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-04-16 00:10:20 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-04-16 00:10:20 +0200 |
commit | 5512320c9f6f2acd7972c05400473c2338325339 (patch) | |
tree | 42e053788513385401abf94fb57bf13aa53d4658 /fs | |
parent | Linux 5.1-rc5 (diff) | |
parent | fs/dax: Deposit pagetable even when installing zero page (diff) | |
download | linux-5512320c9f6f2acd7972c05400473c2338325339.tar.xz linux-5512320c9f6f2acd7972c05400473c2338325339.zip |
Merge tag 'fsdax-fix-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull fsdax fix from Dan Williams:
"A single filesystem-dax fix. It has been lingering in -next for a long
while and there are no other fsdax fixes on the horizon:
- Avoid a crash scenario with architectures like powerpc that require
'pgtable_deposit' for the zero page"
* tag 'fsdax-fix-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
fs/dax: Deposit pagetable even when installing zero page
Diffstat (limited to 'fs')
-rw-r--r-- | fs/dax.c | 15 |
1 files changed, 15 insertions, 0 deletions
@@ -33,6 +33,7 @@ #include <linux/sizes.h> #include <linux/mmu_notifier.h> #include <linux/iomap.h> +#include <asm/pgalloc.h> #include "internal.h" #define CREATE_TRACE_POINTS @@ -1407,7 +1408,9 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, { struct address_space *mapping = vmf->vma->vm_file->f_mapping; unsigned long pmd_addr = vmf->address & PMD_MASK; + struct vm_area_struct *vma = vmf->vma; struct inode *inode = mapping->host; + pgtable_t pgtable = NULL; struct page *zero_page; spinlock_t *ptl; pmd_t pmd_entry; @@ -1422,12 +1425,22 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, *entry = dax_insert_entry(xas, mapping, vmf, *entry, pfn, DAX_PMD | DAX_ZERO_PAGE, false); + if (arch_needs_pgtable_deposit()) { + pgtable = pte_alloc_one(vma->vm_mm); + if (!pgtable) + return VM_FAULT_OOM; + } + ptl = pmd_lock(vmf->vma->vm_mm, vmf->pmd); if (!pmd_none(*(vmf->pmd))) { spin_unlock(ptl); goto fallback; } + if (pgtable) { + pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable); + mm_inc_nr_ptes(vma->vm_mm); + } pmd_entry = mk_pmd(zero_page, vmf->vma->vm_page_prot); pmd_entry = pmd_mkhuge(pmd_entry); set_pmd_at(vmf->vma->vm_mm, pmd_addr, vmf->pmd, pmd_entry); @@ -1436,6 +1449,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf, return VM_FAULT_NOPAGE; fallback: + if (pgtable) + pte_free(vma->vm_mm, pgtable); trace_dax_pmd_load_hole_fallback(inode, vmf, zero_page, *entry); return VM_FAULT_FALLBACK; } |