diff options
| -rw-r--r-- | fs/userfaultfd.c | 5 | ||||
| -rw-r--r-- | include/linux/mm.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/userfaultfd.h | 8 | ||||
| -rw-r--r-- | mm/hugetlb.c | 6 | ||||
| -rw-r--r-- | mm/memory.c | 1 | ||||
| -rw-r--r-- | mm/swapfile.c | 1 |
6 files changed, 19 insertions, 5 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 8e03b3d3f5fa..aa0c47cb0d16 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -198,6 +198,9 @@ static inline struct uffd_msg userfault_msg(unsigned long address, struct uffd_msg msg; msg_init(&msg); msg.event = UFFD_EVENT_PAGEFAULT; + + if (!(features & UFFD_FEATURE_EXACT_ADDRESS)) + address &= PAGE_MASK; msg.arg.pagefault.address = address; /* * These flags indicate why the userfault occurred: @@ -482,7 +485,7 @@ vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason) init_waitqueue_func_entry(&uwq.wq, userfaultfd_wake_function); uwq.wq.private = current; - uwq.msg = userfault_msg(vmf->address, vmf->flags, reason, + uwq.msg = userfault_msg(vmf->real_address, vmf->flags, reason, ctx->features); uwq.ctx = ctx; uwq.waken = false; diff --git a/include/linux/mm.h b/include/linux/mm.h index 9d58321386cc..0e4fd101616e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -478,7 +478,8 @@ struct vm_fault { struct vm_area_struct *vma; /* Target VMA */ gfp_t gfp_mask; /* gfp mask to be used for allocations */ pgoff_t pgoff; /* Logical page offset based on vma */ - unsigned long address; /* Faulting virtual address */ + unsigned long address; /* Faulting virtual address - masked */ + unsigned long real_address; /* Faulting virtual address - unmasked */ }; enum fault_flag flags; /* FAULT_FLAG_xxx flags * XXX: should really be 'const' */ diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 05b31d60acf6..ef739054cb1c 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -32,7 +32,8 @@ UFFD_FEATURE_SIGBUS | \ UFFD_FEATURE_THREAD_ID | \ UFFD_FEATURE_MINOR_HUGETLBFS | \ - UFFD_FEATURE_MINOR_SHMEM) + UFFD_FEATURE_MINOR_SHMEM | \ + UFFD_FEATURE_EXACT_ADDRESS) #define UFFD_API_IOCTLS \ ((__u64)1 << _UFFDIO_REGISTER | \ (__u64)1 << _UFFDIO_UNREGISTER | \ @@ -189,6 +190,10 @@ struct uffdio_api { * * UFFD_FEATURE_MINOR_SHMEM indicates the same support as * UFFD_FEATURE_MINOR_HUGETLBFS, but for shmem-backed pages instead. + * + * UFFD_FEATURE_EXACT_ADDRESS indicates that the exact address of page + * faults would be provided and the offset within the page would not be + * masked. */ #define UFFD_FEATURE_PAGEFAULT_FLAG_WP (1<<0) #define UFFD_FEATURE_EVENT_FORK (1<<1) @@ -201,6 +206,7 @@ struct uffdio_api { #define UFFD_FEATURE_THREAD_ID (1<<8) #define UFFD_FEATURE_MINOR_HUGETLBFS (1<<9) #define UFFD_FEATURE_MINOR_SHMEM (1<<10) +#define UFFD_FEATURE_EXACT_ADDRESS (1<<11) __u64 features; __u64 ioctls; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f425147e4ce3..75b41879e9e9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5341,6 +5341,7 @@ static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, pgoff_t idx, unsigned int flags, unsigned long haddr, + unsigned long addr, unsigned long reason) { vm_fault_t ret; @@ -5348,6 +5349,7 @@ static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, struct vm_fault vmf = { .vma = vma, .address = haddr, + .real_address = addr, .flags = flags, /* @@ -5416,7 +5418,7 @@ retry: /* Check for page in userfault range */ if (userfaultfd_missing(vma)) { ret = hugetlb_handle_userfault(vma, mapping, idx, - flags, haddr, + flags, haddr, address, VM_UFFD_MISSING); goto out; } @@ -5480,7 +5482,7 @@ retry: unlock_page(page); put_page(page); ret = hugetlb_handle_userfault(vma, mapping, idx, - flags, haddr, + flags, haddr, address, VM_UFFD_MINOR); goto out; } diff --git a/mm/memory.c b/mm/memory.c index 1a55b4c5b5db..e0f3410fa70c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4633,6 +4633,7 @@ static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma, struct vm_fault vmf = { .vma = vma, .address = address & PAGE_MASK, + .real_address = address, .flags = flags, .pgoff = linear_page_index(vma, address), .gfp_mask = __get_fault_gfp_mask(vma), diff --git a/mm/swapfile.c b/mm/swapfile.c index bf0df7aa7158..33c7abb16610 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1951,6 +1951,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, struct vm_fault vmf = { .vma = vma, .address = addr, + .real_address = addr, .pmd = pmd, }; |