Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/mm/hmm.c b/mm/hmm.c
index 902f5fa..cbe9d0c 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -26,299 +26,67 @@
#include <linux/mmu_notifier.h>
#include <linux/memory_hotplug.h>
-static struct mmu_notifier *hmm_alloc_notifier(struct mm_struct *mm)
-{
- struct hmm *hmm;
-
- hmm = kzalloc(sizeof(*hmm), GFP_KERNEL);
- if (!hmm)
- return ERR_PTR(-ENOMEM);
-
- init_waitqueue_head(&hmm->wq);
- INIT_LIST_HEAD(&hmm->mirrors);
- init_rwsem(&hmm->mirrors_sem);
- INIT_LIST_HEAD(&hmm->ranges);
- spin_lock_init(&hmm->ranges_lock);
- hmm->notifiers = 0;
- return &hmm->mmu_notifier;
-}
-
-static void hmm_free_notifier(struct mmu_notifier *mn)
-{
- struct hmm *hmm = container_of(mn, struct hmm, mmu_notifier);
-
- WARN_ON(!list_empty(&hmm->ranges));
- WARN_ON(!list_empty(&hmm->mirrors));
- kfree(hmm);
-}
-
-static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm)
-{
- struct hmm *hmm = container_of(mn, struct hmm, mmu_notifier);
- struct hmm_mirror *mirror;
-
- /*
- * Since hmm_range_register() holds the mmget() lock hmm_release() is
- * prevented as long as a range exists.
- */
- WARN_ON(!list_empty_careful(&hmm->ranges));
-
- down_read(&hmm->mirrors_sem);
- list_for_each_entry(mirror, &hmm->mirrors, list) {
- /*
- * Note: The driver is not allowed to trigger
- * hmm_mirror_unregister() from this thread.
- */
- if (mirror->ops->release)
- mirror->ops->release(mirror);
- }
- up_read(&hmm->mirrors_sem);
-}
-
-static void notifiers_decrement(struct hmm *hmm)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&hmm->ranges_lock, flags);
- hmm->notifiers--;
- if (!hmm->notifiers) {
- struct hmm_range *range;
-
- list_for_each_entry(range, &hmm->ranges, list) {
- if (range->valid)
- continue;
- range->valid = true;
- }
- wake_up_all(&hmm->wq);
- }
- spin_unlock_irqrestore(&hmm->ranges_lock, flags);
-}
-
-static int hmm_invalidate_range_start(struct mmu_notifier *mn,
- const struct mmu_notifier_range *nrange)
-{
- struct hmm *hmm = container_of(mn, struct hmm, mmu_notifier);
- struct hmm_mirror *mirror;
- struct hmm_range *range;
- unsigned long flags;
- int ret = 0;
-
- spin_lock_irqsave(&hmm->ranges_lock, flags);
- hmm->notifiers++;
- list_for_each_entry(range, &hmm->ranges, list) {
- if (nrange->end < range->start || nrange->start >= range->end)
- continue;
-
- range->valid = false;
- }
- spin_unlock_irqrestore(&hmm->ranges_lock, flags);
-
- if (mmu_notifier_range_blockable(nrange))
- down_read(&hmm->mirrors_sem);
- else if (!down_read_trylock(&hmm->mirrors_sem)) {
- ret = -EAGAIN;
- goto out;
- }
-
- list_for_each_entry(mirror, &hmm->mirrors, list) {
- int rc;
-
- rc = mirror->ops->sync_cpu_device_pagetables(mirror, nrange);
- if (rc) {
- if (WARN_ON(mmu_notifier_range_blockable(nrange) ||
- rc != -EAGAIN))
- continue;
- ret = -EAGAIN;
- break;
- }
- }
- up_read(&hmm->mirrors_sem);
-
-out:
- if (ret)
- notifiers_decrement(hmm);
- return ret;
-}
-
-static void hmm_invalidate_range_end(struct mmu_notifier *mn,
- const struct mmu_notifier_range *nrange)
-{
- struct hmm *hmm = container_of(mn, struct hmm, mmu_notifier);
-
- notifiers_decrement(hmm);
-}
-
-static const struct mmu_notifier_ops hmm_mmu_notifier_ops = {
- .release = hmm_release,
- .invalidate_range_start = hmm_invalidate_range_start,
- .invalidate_range_end = hmm_invalidate_range_end,
- .alloc_notifier = hmm_alloc_notifier,
- .free_notifier = hmm_free_notifier,
-};
-
-/*
- * hmm_mirror_register() - register a mirror against an mm
- *
- * @mirror: new mirror struct to register
- * @mm: mm to register against
- * Return: 0 on success, -ENOMEM if no memory, -EINVAL if invalid arguments
- *
- * To start mirroring a process address space, the device driver must register
- * an HMM mirror struct.
- *
- * The caller cannot unregister the hmm_mirror while any ranges are
- * registered.
- *
- * Callers using this function must put a call to mmu_notifier_synchronize()
- * in their module exit functions.
- */
-int hmm_mirror_register(struct hmm_mirror *mirror, struct mm_struct *mm)
-{
- struct mmu_notifier *mn;
-
- lockdep_assert_held_write(&mm->mmap_sem);
-
- /* Sanity check */
- if (!mm || !mirror || !mirror->ops)
- return -EINVAL;
-
- mn = mmu_notifier_get_locked(&hmm_mmu_notifier_ops, mm);
- if (IS_ERR(mn))
- return PTR_ERR(mn);
- mirror->hmm = container_of(mn, struct hmm, mmu_notifier);
-
- down_write(&mirror->hmm->mirrors_sem);
- list_add(&mirror->list, &mirror->hmm->mirrors);
- up_write(&mirror->hmm->mirrors_sem);
-
- return 0;
-}
-EXPORT_SYMBOL(hmm_mirror_register);
-
-/*
- * hmm_mirror_unregister() - unregister a mirror
- *
- * @mirror: mirror struct to unregister
- *
- * Stop mirroring a process address space, and cleanup.
- */
-void hmm_mirror_unregister(struct hmm_mirror *mirror)
-{
- struct hmm *hmm = mirror->hmm;
-
- down_write(&hmm->mirrors_sem);
- list_del(&mirror->list);
- up_write(&hmm->mirrors_sem);
- mmu_notifier_put(&hmm->mmu_notifier);
-}
-EXPORT_SYMBOL(hmm_mirror_unregister);
-
struct hmm_vma_walk {
struct hmm_range *range;
- struct dev_pagemap *pgmap;
unsigned long last;
- unsigned int flags;
};
-static int hmm_vma_do_fault(struct mm_walk *walk, unsigned long addr,
- bool write_fault, uint64_t *pfn)
+enum {
+ HMM_NEED_FAULT = 1 << 0,
+ HMM_NEED_WRITE_FAULT = 1 << 1,
+ HMM_NEED_ALL_BITS = HMM_NEED_FAULT | HMM_NEED_WRITE_FAULT,
+};
+
+static int hmm_pfns_fill(unsigned long addr, unsigned long end,
+ struct hmm_range *range, unsigned long cpu_flags)
{
- unsigned int flags = FAULT_FLAG_REMOTE;
- struct hmm_vma_walk *hmm_vma_walk = walk->private;
- struct hmm_range *range = hmm_vma_walk->range;
- struct vm_area_struct *vma = walk->vma;
- vm_fault_t ret;
+ unsigned long i = (addr - range->start) >> PAGE_SHIFT;
- if (!vma)
- goto err;
-
- if (hmm_vma_walk->flags & HMM_FAULT_ALLOW_RETRY)
- flags |= FAULT_FLAG_ALLOW_RETRY;
- if (write_fault)
- flags |= FAULT_FLAG_WRITE;
-
- ret = handle_mm_fault(vma, addr, flags);
- if (ret & VM_FAULT_RETRY) {
- /* Note, handle_mm_fault did up_read(&mm->mmap_sem)) */
- return -EAGAIN;
- }
- if (ret & VM_FAULT_ERROR)
- goto err;
-
- return -EBUSY;
-
-err:
- *pfn = range->values[HMM_PFN_ERROR];
- return -EFAULT;
-}
-
-static int hmm_pfns_bad(unsigned long addr,
- unsigned long end,
- struct mm_walk *walk)
-{
- struct hmm_vma_walk *hmm_vma_walk = walk->private;
- struct hmm_range *range = hmm_vma_walk->range;
- uint64_t *pfns = range->pfns;
- unsigned long i;
-
- i = (addr - range->start) >> PAGE_SHIFT;
for (; addr < end; addr += PAGE_SIZE, i++)
- pfns[i] = range->values[HMM_PFN_ERROR];
-
+ range->hmm_pfns[i] = cpu_flags;
return 0;
}
/*
- * hmm_vma_walk_hole_() - handle a range lacking valid pmd or pte(s)
+ * hmm_vma_fault() - fault in a range lacking valid pmd or pte(s)
* @addr: range virtual start address (inclusive)
* @end: range virtual end address (exclusive)
- * @fault: should we fault or not ?
- * @write_fault: write fault ?
+ * @required_fault: HMM_NEED_* flags
* @walk: mm_walk structure
- * Return: 0 on success, -EBUSY after page fault, or page fault error
+ * Return: -EBUSY after page fault, or page fault error
*
* This function will be called whenever pmd_none() or pte_none() returns true,
* or whenever there is no page directory covering the virtual address range.
*/
-static int hmm_vma_walk_hole_(unsigned long addr, unsigned long end,
- bool fault, bool write_fault,
- struct mm_walk *walk)
+static int hmm_vma_fault(unsigned long addr, unsigned long end,
+ unsigned int required_fault, struct mm_walk *walk)
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
- struct hmm_range *range = hmm_vma_walk->range;
- uint64_t *pfns = range->pfns;
- unsigned long i;
+ struct vm_area_struct *vma = walk->vma;
+ unsigned int fault_flags = FAULT_FLAG_REMOTE;
+ WARN_ON_ONCE(!required_fault);
hmm_vma_walk->last = addr;
- i = (addr - range->start) >> PAGE_SHIFT;
- if (write_fault && walk->vma && !(walk->vma->vm_flags & VM_WRITE))
- return -EPERM;
-
- for (; addr < end; addr += PAGE_SIZE, i++) {
- pfns[i] = range->values[HMM_PFN_NONE];
- if (fault || write_fault) {
- int ret;
-
- ret = hmm_vma_do_fault(walk, addr, write_fault,
- &pfns[i]);
- if (ret != -EBUSY)
- return ret;
- }
+ if (required_fault & HMM_NEED_WRITE_FAULT) {
+ if (!(vma->vm_flags & VM_WRITE))
+ return -EPERM;
+ fault_flags |= FAULT_FLAG_WRITE;
}
- return (fault || write_fault) ? -EBUSY : 0;
+ for (; addr < end; addr += PAGE_SIZE)
+ if (handle_mm_fault(vma, addr, fault_flags, NULL) &
+ VM_FAULT_ERROR)
+ return -EFAULT;
+ return -EBUSY;
}
-static inline void hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
- uint64_t pfns, uint64_t cpu_flags,
- bool *fault, bool *write_fault)
+static unsigned int hmm_pte_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
+ unsigned long pfn_req_flags,
+ unsigned long cpu_flags)
{
struct hmm_range *range = hmm_vma_walk->range;
- if (hmm_vma_walk->flags & HMM_FAULT_SNAPSHOT)
- return;
-
/*
* So we not only consider the individual per page request we also
* consider the default flags requested for the range. The API can
@@ -329,224 +97,223 @@
* waste to have the user pre-fill the pfn arrays with a default
* flags value.
*/
- pfns = (pfns & range->pfn_flags_mask) | range->default_flags;
+ pfn_req_flags &= range->pfn_flags_mask;
+ pfn_req_flags |= range->default_flags;
/* We aren't ask to do anything ... */
- if (!(pfns & range->flags[HMM_PFN_VALID]))
- return;
- /* If this is device memory then only fault if explicitly requested */
- if ((cpu_flags & range->flags[HMM_PFN_DEVICE_PRIVATE])) {
- /* Do we fault on device memory ? */
- if (pfns & range->flags[HMM_PFN_DEVICE_PRIVATE]) {
- *write_fault = pfns & range->flags[HMM_PFN_WRITE];
- *fault = true;
- }
- return;
- }
+ if (!(pfn_req_flags & HMM_PFN_REQ_FAULT))
+ return 0;
+
+ /* Need to write fault ? */
+ if ((pfn_req_flags & HMM_PFN_REQ_WRITE) &&
+ !(cpu_flags & HMM_PFN_WRITE))
+ return HMM_NEED_FAULT | HMM_NEED_WRITE_FAULT;
/* If CPU page table is not valid then we need to fault */
- *fault = !(cpu_flags & range->flags[HMM_PFN_VALID]);
- /* Need to write fault ? */
- if ((pfns & range->flags[HMM_PFN_WRITE]) &&
- !(cpu_flags & range->flags[HMM_PFN_WRITE])) {
- *write_fault = true;
- *fault = true;
- }
+ if (!(cpu_flags & HMM_PFN_VALID))
+ return HMM_NEED_FAULT;
+ return 0;
}
-static void hmm_range_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
- const uint64_t *pfns, unsigned long npages,
- uint64_t cpu_flags, bool *fault,
- bool *write_fault)
+static unsigned int
+hmm_range_need_fault(const struct hmm_vma_walk *hmm_vma_walk,
+ const unsigned long hmm_pfns[], unsigned long npages,
+ unsigned long cpu_flags)
{
+ struct hmm_range *range = hmm_vma_walk->range;
+ unsigned int required_fault = 0;
unsigned long i;
- if (hmm_vma_walk->flags & HMM_FAULT_SNAPSHOT) {
- *fault = *write_fault = false;
- return;
- }
+ /*
+ * If the default flags do not request to fault pages, and the mask does
+ * not allow for individual pages to be faulted, then
+ * hmm_pte_need_fault() will always return 0.
+ */
+ if (!((range->default_flags | range->pfn_flags_mask) &
+ HMM_PFN_REQ_FAULT))
+ return 0;
- *fault = *write_fault = false;
for (i = 0; i < npages; ++i) {
- hmm_pte_need_fault(hmm_vma_walk, pfns[i], cpu_flags,
- fault, write_fault);
- if ((*write_fault))
- return;
+ required_fault |= hmm_pte_need_fault(hmm_vma_walk, hmm_pfns[i],
+ cpu_flags);
+ if (required_fault == HMM_NEED_ALL_BITS)
+ return required_fault;
}
+ return required_fault;
}
static int hmm_vma_walk_hole(unsigned long addr, unsigned long end,
- struct mm_walk *walk)
+ __always_unused int depth, struct mm_walk *walk)
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- bool fault, write_fault;
+ unsigned int required_fault;
unsigned long i, npages;
- uint64_t *pfns;
+ unsigned long *hmm_pfns;
i = (addr - range->start) >> PAGE_SHIFT;
npages = (end - addr) >> PAGE_SHIFT;
- pfns = &range->pfns[i];
- hmm_range_need_fault(hmm_vma_walk, pfns, npages,
- 0, &fault, &write_fault);
- return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk);
+ hmm_pfns = &range->hmm_pfns[i];
+ required_fault =
+ hmm_range_need_fault(hmm_vma_walk, hmm_pfns, npages, 0);
+ if (!walk->vma) {
+ if (required_fault)
+ return -EFAULT;
+ return hmm_pfns_fill(addr, end, range, HMM_PFN_ERROR);
+ }
+ if (required_fault)
+ return hmm_vma_fault(addr, end, required_fault, walk);
+ return hmm_pfns_fill(addr, end, range, 0);
}
-static inline uint64_t pmd_to_hmm_pfn_flags(struct hmm_range *range, pmd_t pmd)
+static inline unsigned long hmm_pfn_flags_order(unsigned long order)
+{
+ return order << HMM_PFN_ORDER_SHIFT;
+}
+
+static inline unsigned long pmd_to_hmm_pfn_flags(struct hmm_range *range,
+ pmd_t pmd)
{
if (pmd_protnone(pmd))
return 0;
- return pmd_write(pmd) ? range->flags[HMM_PFN_VALID] |
- range->flags[HMM_PFN_WRITE] :
- range->flags[HMM_PFN_VALID];
+ return (pmd_write(pmd) ? (HMM_PFN_VALID | HMM_PFN_WRITE) :
+ HMM_PFN_VALID) |
+ hmm_pfn_flags_order(PMD_SHIFT - PAGE_SHIFT);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
- unsigned long end, uint64_t *pfns, pmd_t pmd)
+ unsigned long end, unsigned long hmm_pfns[],
+ pmd_t pmd)
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
unsigned long pfn, npages, i;
- bool fault, write_fault;
- uint64_t cpu_flags;
+ unsigned int required_fault;
+ unsigned long cpu_flags;
npages = (end - addr) >> PAGE_SHIFT;
cpu_flags = pmd_to_hmm_pfn_flags(range, pmd);
- hmm_range_need_fault(hmm_vma_walk, pfns, npages, cpu_flags,
- &fault, &write_fault);
-
- if (pmd_protnone(pmd) || fault || write_fault)
- return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk);
+ required_fault =
+ hmm_range_need_fault(hmm_vma_walk, hmm_pfns, npages, cpu_flags);
+ if (required_fault)
+ return hmm_vma_fault(addr, end, required_fault, walk);
pfn = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
- for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++) {
- if (pmd_devmap(pmd)) {
- hmm_vma_walk->pgmap = get_dev_pagemap(pfn,
- hmm_vma_walk->pgmap);
- if (unlikely(!hmm_vma_walk->pgmap))
- return -EBUSY;
- }
- pfns[i] = hmm_device_entry_from_pfn(range, pfn) | cpu_flags;
- }
- if (hmm_vma_walk->pgmap) {
- put_dev_pagemap(hmm_vma_walk->pgmap);
- hmm_vma_walk->pgmap = NULL;
- }
- hmm_vma_walk->last = end;
+ for (i = 0; addr < end; addr += PAGE_SIZE, i++, pfn++)
+ hmm_pfns[i] = pfn | cpu_flags;
return 0;
}
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
/* stub to allow the code below to compile */
int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr,
- unsigned long end, uint64_t *pfns, pmd_t pmd);
+ unsigned long end, unsigned long hmm_pfns[], pmd_t pmd);
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-static inline uint64_t pte_to_hmm_pfn_flags(struct hmm_range *range, pte_t pte)
+static inline bool hmm_is_device_private_entry(struct hmm_range *range,
+ swp_entry_t entry)
+{
+ return is_device_private_entry(entry) &&
+ device_private_entry_to_page(entry)->pgmap->owner ==
+ range->dev_private_owner;
+}
+
+static inline unsigned long pte_to_hmm_pfn_flags(struct hmm_range *range,
+ pte_t pte)
{
if (pte_none(pte) || !pte_present(pte) || pte_protnone(pte))
return 0;
- return pte_write(pte) ? range->flags[HMM_PFN_VALID] |
- range->flags[HMM_PFN_WRITE] :
- range->flags[HMM_PFN_VALID];
+ return pte_write(pte) ? (HMM_PFN_VALID | HMM_PFN_WRITE) : HMM_PFN_VALID;
}
static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr,
unsigned long end, pmd_t *pmdp, pte_t *ptep,
- uint64_t *pfn)
+ unsigned long *hmm_pfn)
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- bool fault, write_fault;
- uint64_t cpu_flags;
+ unsigned int required_fault;
+ unsigned long cpu_flags;
pte_t pte = *ptep;
- uint64_t orig_pfn = *pfn;
-
- *pfn = range->values[HMM_PFN_NONE];
- fault = write_fault = false;
+ uint64_t pfn_req_flags = *hmm_pfn;
if (pte_none(pte)) {
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, 0,
- &fault, &write_fault);
- if (fault || write_fault)
+ required_fault =
+ hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0);
+ if (required_fault)
goto fault;
+ *hmm_pfn = 0;
return 0;
}
if (!pte_present(pte)) {
swp_entry_t entry = pte_to_swp_entry(pte);
- if (!non_swap_entry(entry)) {
- cpu_flags = pte_to_hmm_pfn_flags(range, pte);
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, cpu_flags,
- &fault, &write_fault);
- if (fault || write_fault)
- goto fault;
+ /*
+ * Never fault in device private pages, but just report
+ * the PFN even if not present.
+ */
+ if (hmm_is_device_private_entry(range, entry)) {
+ cpu_flags = HMM_PFN_VALID;
+ if (is_write_device_private_entry(entry))
+ cpu_flags |= HMM_PFN_WRITE;
+ *hmm_pfn = device_private_entry_to_pfn(entry) |
+ cpu_flags;
return 0;
}
- /*
- * This is a special swap entry, ignore migration, use
- * device and report anything else as error.
- */
- if (is_device_private_entry(entry)) {
- cpu_flags = range->flags[HMM_PFN_VALID] |
- range->flags[HMM_PFN_DEVICE_PRIVATE];
- cpu_flags |= is_write_device_private_entry(entry) ?
- range->flags[HMM_PFN_WRITE] : 0;
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, cpu_flags,
- &fault, &write_fault);
- if (fault || write_fault)
- goto fault;
- *pfn = hmm_device_entry_from_pfn(range,
- swp_offset(entry));
- *pfn |= cpu_flags;
+ required_fault =
+ hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0);
+ if (!required_fault) {
+ *hmm_pfn = 0;
return 0;
}
+ if (!non_swap_entry(entry))
+ goto fault;
+
if (is_migration_entry(entry)) {
- if (fault || write_fault) {
- pte_unmap(ptep);
- hmm_vma_walk->last = addr;
- migration_entry_wait(walk->mm, pmdp, addr);
- return -EBUSY;
- }
- return 0;
+ pte_unmap(ptep);
+ hmm_vma_walk->last = addr;
+ migration_entry_wait(walk->mm, pmdp, addr);
+ return -EBUSY;
}
/* Report error for everything else */
- *pfn = range->values[HMM_PFN_ERROR];
+ pte_unmap(ptep);
return -EFAULT;
- } else {
- cpu_flags = pte_to_hmm_pfn_flags(range, pte);
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, cpu_flags,
- &fault, &write_fault);
}
- if (fault || write_fault)
+ cpu_flags = pte_to_hmm_pfn_flags(range, pte);
+ required_fault =
+ hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, cpu_flags);
+ if (required_fault)
goto fault;
- if (pte_devmap(pte)) {
- hmm_vma_walk->pgmap = get_dev_pagemap(pte_pfn(pte),
- hmm_vma_walk->pgmap);
- if (unlikely(!hmm_vma_walk->pgmap))
- return -EBUSY;
- } else if (IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL) && pte_special(pte)) {
- *pfn = range->values[HMM_PFN_SPECIAL];
- return -EFAULT;
+ /*
+ * Bypass devmap pte such as DAX page when all pfn requested
+ * flags(pfn_req_flags) are fulfilled.
+ * Since each architecture defines a struct page for the zero page, just
+ * fall through and treat it like a normal page.
+ */
+ if (!vm_normal_page(walk->vma, addr, pte) &&
+ !pte_devmap(pte) &&
+ !is_zero_pfn(pte_pfn(pte))) {
+ if (hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, 0)) {
+ pte_unmap(ptep);
+ return -EFAULT;
+ }
+ *hmm_pfn = HMM_PFN_ERROR;
+ return 0;
}
- *pfn = hmm_device_entry_from_pfn(range, pte_pfn(pte)) | cpu_flags;
+ *hmm_pfn = pte_pfn(pte) | cpu_flags;
return 0;
fault:
- if (hmm_vma_walk->pgmap) {
- put_dev_pagemap(hmm_vma_walk->pgmap);
- hmm_vma_walk->pgmap = NULL;
- }
pte_unmap(ptep);
/* Fault any virtual address we were asked to fault */
- return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk);
+ return hmm_vma_fault(addr, end, required_fault, walk);
}
static int hmm_vma_walk_pmd(pmd_t *pmdp,
@@ -556,35 +323,32 @@
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- uint64_t *pfns = range->pfns;
- unsigned long addr = start, i;
+ unsigned long *hmm_pfns =
+ &range->hmm_pfns[(start - range->start) >> PAGE_SHIFT];
+ unsigned long npages = (end - start) >> PAGE_SHIFT;
+ unsigned long addr = start;
pte_t *ptep;
pmd_t pmd;
again:
pmd = READ_ONCE(*pmdp);
if (pmd_none(pmd))
- return hmm_vma_walk_hole(start, end, walk);
+ return hmm_vma_walk_hole(start, end, -1, walk);
if (thp_migration_supported() && is_pmd_migration_entry(pmd)) {
- bool fault, write_fault;
- unsigned long npages;
- uint64_t *pfns;
-
- i = (addr - range->start) >> PAGE_SHIFT;
- npages = (end - addr) >> PAGE_SHIFT;
- pfns = &range->pfns[i];
-
- hmm_range_need_fault(hmm_vma_walk, pfns, npages,
- 0, &fault, &write_fault);
- if (fault || write_fault) {
+ if (hmm_range_need_fault(hmm_vma_walk, hmm_pfns, npages, 0)) {
hmm_vma_walk->last = addr;
pmd_migration_entry_wait(walk->mm, pmdp);
return -EBUSY;
}
- return 0;
- } else if (!pmd_present(pmd))
- return hmm_pfns_bad(start, end, walk);
+ return hmm_pfns_fill(start, end, range, 0);
+ }
+
+ if (!pmd_present(pmd)) {
+ if (hmm_range_need_fault(hmm_vma_walk, hmm_pfns, npages, 0))
+ return -EFAULT;
+ return hmm_pfns_fill(start, end, range, HMM_PFN_ERROR);
+ }
if (pmd_devmap(pmd) || pmd_trans_huge(pmd)) {
/*
@@ -601,8 +365,7 @@
if (!pmd_devmap(pmd) && !pmd_trans_huge(pmd))
goto again;
- i = (addr - range->start) >> PAGE_SHIFT;
- return hmm_vma_handle_pmd(walk, addr, end, &pfns[i], pmd);
+ return hmm_vma_handle_pmd(walk, addr, end, hmm_pfns, pmd);
}
/*
@@ -611,46 +374,36 @@
* entry pointing to pte directory or it is a bad pmd that will not
* recover.
*/
- if (pmd_bad(pmd))
- return hmm_pfns_bad(start, end, walk);
+ if (pmd_bad(pmd)) {
+ if (hmm_range_need_fault(hmm_vma_walk, hmm_pfns, npages, 0))
+ return -EFAULT;
+ return hmm_pfns_fill(start, end, range, HMM_PFN_ERROR);
+ }
ptep = pte_offset_map(pmdp, addr);
- i = (addr - range->start) >> PAGE_SHIFT;
- for (; addr < end; addr += PAGE_SIZE, ptep++, i++) {
+ for (; addr < end; addr += PAGE_SIZE, ptep++, hmm_pfns++) {
int r;
- r = hmm_vma_handle_pte(walk, addr, end, pmdp, ptep, &pfns[i]);
+ r = hmm_vma_handle_pte(walk, addr, end, pmdp, ptep, hmm_pfns);
if (r) {
- /* hmm_vma_handle_pte() did unmap pte directory */
- hmm_vma_walk->last = addr;
+ /* hmm_vma_handle_pte() did pte_unmap() */
return r;
}
}
- if (hmm_vma_walk->pgmap) {
- /*
- * We do put_dev_pagemap() here and not in hmm_vma_handle_pte()
- * so that we can leverage get_dev_pagemap() optimization which
- * will not re-take a reference on a pgmap if we already have
- * one.
- */
- put_dev_pagemap(hmm_vma_walk->pgmap);
- hmm_vma_walk->pgmap = NULL;
- }
pte_unmap(ptep - 1);
-
- hmm_vma_walk->last = addr;
return 0;
}
#if defined(CONFIG_ARCH_HAS_PTE_DEVMAP) && \
defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
-static inline uint64_t pud_to_hmm_pfn_flags(struct hmm_range *range, pud_t pud)
+static inline unsigned long pud_to_hmm_pfn_flags(struct hmm_range *range,
+ pud_t pud)
{
if (!pud_present(pud))
return 0;
- return pud_write(pud) ? range->flags[HMM_PFN_VALID] |
- range->flags[HMM_PFN_WRITE] :
- range->flags[HMM_PFN_VALID];
+ return (pud_write(pud) ? (HMM_PFN_VALID | HMM_PFN_WRITE) :
+ HMM_PFN_VALID) |
+ hmm_pfn_flags_order(PUD_SHIFT - PAGE_SHIFT);
}
static int hmm_vma_walk_pud(pud_t *pudp, unsigned long start, unsigned long end,
@@ -658,65 +411,58 @@
{
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
- unsigned long addr = start, next;
- pmd_t *pmdp;
+ unsigned long addr = start;
pud_t pud;
- int ret;
+ int ret = 0;
+ spinlock_t *ptl = pud_trans_huge_lock(pudp, walk->vma);
-again:
+ if (!ptl)
+ return 0;
+
+ /* Normally we don't want to split the huge page */
+ walk->action = ACTION_CONTINUE;
+
pud = READ_ONCE(*pudp);
- if (pud_none(pud))
- return hmm_vma_walk_hole(start, end, walk);
+ if (pud_none(pud)) {
+ spin_unlock(ptl);
+ return hmm_vma_walk_hole(start, end, -1, walk);
+ }
if (pud_huge(pud) && pud_devmap(pud)) {
unsigned long i, npages, pfn;
- uint64_t *pfns, cpu_flags;
- bool fault, write_fault;
+ unsigned int required_fault;
+ unsigned long *hmm_pfns;
+ unsigned long cpu_flags;
- if (!pud_present(pud))
- return hmm_vma_walk_hole(start, end, walk);
+ if (!pud_present(pud)) {
+ spin_unlock(ptl);
+ return hmm_vma_walk_hole(start, end, -1, walk);
+ }
i = (addr - range->start) >> PAGE_SHIFT;
npages = (end - addr) >> PAGE_SHIFT;
- pfns = &range->pfns[i];
+ hmm_pfns = &range->hmm_pfns[i];
cpu_flags = pud_to_hmm_pfn_flags(range, pud);
- hmm_range_need_fault(hmm_vma_walk, pfns, npages,
- cpu_flags, &fault, &write_fault);
- if (fault || write_fault)
- return hmm_vma_walk_hole_(addr, end, fault,
- write_fault, walk);
+ required_fault = hmm_range_need_fault(hmm_vma_walk, hmm_pfns,
+ npages, cpu_flags);
+ if (required_fault) {
+ spin_unlock(ptl);
+ return hmm_vma_fault(addr, end, required_fault, walk);
+ }
pfn = pud_pfn(pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
- for (i = 0; i < npages; ++i, ++pfn) {
- hmm_vma_walk->pgmap = get_dev_pagemap(pfn,
- hmm_vma_walk->pgmap);
- if (unlikely(!hmm_vma_walk->pgmap))
- return -EBUSY;
- pfns[i] = hmm_device_entry_from_pfn(range, pfn) |
- cpu_flags;
- }
- if (hmm_vma_walk->pgmap) {
- put_dev_pagemap(hmm_vma_walk->pgmap);
- hmm_vma_walk->pgmap = NULL;
- }
- hmm_vma_walk->last = end;
- return 0;
+ for (i = 0; i < npages; ++i, ++pfn)
+ hmm_pfns[i] = pfn | cpu_flags;
+ goto out_unlock;
}
- split_huge_pud(walk->vma, pudp, addr);
- if (pud_none(*pudp))
- goto again;
+ /* Ask for the PUD to be split */
+ walk->action = ACTION_SUBTREE;
- pmdp = pmd_offset(pudp, addr);
- do {
- next = pmd_addr_end(addr, end);
- ret = hmm_vma_walk_pmd(pmdp, addr, next, walk);
- if (ret)
- return ret;
- } while (pmdp++, addr = next, addr != end);
-
- return 0;
+out_unlock:
+ spin_unlock(ptl);
+ return ret;
}
#else
#define hmm_vma_walk_pud NULL
@@ -731,368 +477,123 @@
struct hmm_vma_walk *hmm_vma_walk = walk->private;
struct hmm_range *range = hmm_vma_walk->range;
struct vm_area_struct *vma = walk->vma;
- uint64_t orig_pfn, cpu_flags;
- bool fault, write_fault;
+ unsigned int required_fault;
+ unsigned long pfn_req_flags;
+ unsigned long cpu_flags;
spinlock_t *ptl;
pte_t entry;
- int ret = 0;
ptl = huge_pte_lock(hstate_vma(vma), walk->mm, pte);
entry = huge_ptep_get(pte);
i = (start - range->start) >> PAGE_SHIFT;
- orig_pfn = range->pfns[i];
- range->pfns[i] = range->values[HMM_PFN_NONE];
- cpu_flags = pte_to_hmm_pfn_flags(range, entry);
- fault = write_fault = false;
- hmm_pte_need_fault(hmm_vma_walk, orig_pfn, cpu_flags,
- &fault, &write_fault);
- if (fault || write_fault) {
- ret = -ENOENT;
- goto unlock;
+ pfn_req_flags = range->hmm_pfns[i];
+ cpu_flags = pte_to_hmm_pfn_flags(range, entry) |
+ hmm_pfn_flags_order(huge_page_order(hstate_vma(vma)));
+ required_fault =
+ hmm_pte_need_fault(hmm_vma_walk, pfn_req_flags, cpu_flags);
+ if (required_fault) {
+ spin_unlock(ptl);
+ return hmm_vma_fault(addr, end, required_fault, walk);
}
pfn = pte_pfn(entry) + ((start & ~hmask) >> PAGE_SHIFT);
for (; addr < end; addr += PAGE_SIZE, i++, pfn++)
- range->pfns[i] = hmm_device_entry_from_pfn(range, pfn) |
- cpu_flags;
- hmm_vma_walk->last = end;
+ range->hmm_pfns[i] = pfn | cpu_flags;
-unlock:
spin_unlock(ptl);
-
- if (ret == -ENOENT)
- return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk);
-
- return ret;
+ return 0;
}
#else
#define hmm_vma_walk_hugetlb_entry NULL
#endif /* CONFIG_HUGETLB_PAGE */
-static void hmm_pfns_clear(struct hmm_range *range,
- uint64_t *pfns,
- unsigned long addr,
- unsigned long end)
+static int hmm_vma_walk_test(unsigned long start, unsigned long end,
+ struct mm_walk *walk)
{
- for (; addr < end; addr += PAGE_SIZE, pfns++)
- *pfns = range->values[HMM_PFN_NONE];
-}
+ struct hmm_vma_walk *hmm_vma_walk = walk->private;
+ struct hmm_range *range = hmm_vma_walk->range;
+ struct vm_area_struct *vma = walk->vma;
-/*
- * hmm_range_register() - start tracking change to CPU page table over a range
- * @range: range
- * @mm: the mm struct for the range of virtual address
- *
- * Return: 0 on success, -EFAULT if the address space is no longer valid
- *
- * Track updates to the CPU page table see include/linux/hmm.h
- */
-int hmm_range_register(struct hmm_range *range, struct hmm_mirror *mirror)
-{
- struct hmm *hmm = mirror->hmm;
- unsigned long flags;
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)) &&
+ vma->vm_flags & VM_READ)
+ return 0;
- range->valid = false;
- range->hmm = NULL;
-
- if ((range->start & (PAGE_SIZE - 1)) || (range->end & (PAGE_SIZE - 1)))
- return -EINVAL;
- if (range->start >= range->end)
- return -EINVAL;
-
- /* Prevent hmm_release() from running while the range is valid */
- if (!mmget_not_zero(hmm->mmu_notifier.mm))
+ /*
+ * vma ranges that don't have struct page backing them or map I/O
+ * devices directly cannot be handled by hmm_range_fault().
+ *
+ * If the vma does not allow read access, then assume that it does not
+ * allow write access either. HMM does not support architectures that
+ * allow write without read.
+ *
+ * If a fault is requested for an unsupported range then it is a hard
+ * failure.
+ */
+ if (hmm_range_need_fault(hmm_vma_walk,
+ range->hmm_pfns +
+ ((start - range->start) >> PAGE_SHIFT),
+ (end - start) >> PAGE_SHIFT, 0))
return -EFAULT;
- /* Initialize range to track CPU page table updates. */
- spin_lock_irqsave(&hmm->ranges_lock, flags);
+ hmm_pfns_fill(start, end, range, HMM_PFN_ERROR);
- range->hmm = hmm;
- list_add(&range->list, &hmm->ranges);
-
- /*
- * If there are any concurrent notifiers we have to wait for them for
- * the range to be valid (see hmm_range_wait_until_valid()).
- */
- if (!hmm->notifiers)
- range->valid = true;
- spin_unlock_irqrestore(&hmm->ranges_lock, flags);
-
- return 0;
+ /* Skip this vma and continue processing the next vma. */
+ return 1;
}
-EXPORT_SYMBOL(hmm_range_register);
-
-/*
- * hmm_range_unregister() - stop tracking change to CPU page table over a range
- * @range: range
- *
- * Range struct is used to track updates to the CPU page table after a call to
- * hmm_range_register(). See include/linux/hmm.h for how to use it.
- */
-void hmm_range_unregister(struct hmm_range *range)
-{
- struct hmm *hmm = range->hmm;
- unsigned long flags;
-
- spin_lock_irqsave(&hmm->ranges_lock, flags);
- list_del_init(&range->list);
- spin_unlock_irqrestore(&hmm->ranges_lock, flags);
-
- /* Drop reference taken by hmm_range_register() */
- mmput(hmm->mmu_notifier.mm);
-
- /*
- * The range is now invalid and the ref on the hmm is dropped, so
- * poison the pointer. Leave other fields in place, for the caller's
- * use.
- */
- range->valid = false;
- memset(&range->hmm, POISON_INUSE, sizeof(range->hmm));
-}
-EXPORT_SYMBOL(hmm_range_unregister);
static const struct mm_walk_ops hmm_walk_ops = {
.pud_entry = hmm_vma_walk_pud,
.pmd_entry = hmm_vma_walk_pmd,
.pte_hole = hmm_vma_walk_hole,
.hugetlb_entry = hmm_vma_walk_hugetlb_entry,
+ .test_walk = hmm_vma_walk_test,
};
/**
* hmm_range_fault - try to fault some address in a virtual address range
- * @range: range being faulted
- * @flags: HMM_FAULT_* flags
+ * @range: argument structure
*
- * Return: the number of valid pages in range->pfns[] (from range start
- * address), which may be zero. On error one of the following status codes
- * can be returned:
+ * Returns 0 on success or one of the following error codes:
*
* -EINVAL: Invalid arguments or mm or virtual address is in an invalid vma
* (e.g., device file vma).
* -ENOMEM: Out of memory.
* -EPERM: Invalid permission (e.g., asking for write and range is read
* only).
- * -EAGAIN: A page fault needs to be retried and mmap_sem was dropped.
* -EBUSY: The range has been invalidated and the caller needs to wait for
* the invalidation to finish.
- * -EFAULT: Invalid (i.e., either no valid vma or it is illegal to access
- * that range) number of valid pages in range->pfns[] (from
- * range start address).
+ * -EFAULT: A page was requested to be valid and could not be made valid
+ * ie it has no backing VMA or it is illegal to access
*
- * This is similar to a regular CPU page fault except that it will not trigger
- * any memory migration if the memory being faulted is not accessible by CPUs
- * and caller does not ask for migration.
- *
- * On error, for one virtual address in the range, the function will mark the
- * corresponding HMM pfn entry with an error flag.
+ * This is similar to get_user_pages(), except that it can read the page tables
+ * without mutating them (ie causing faults).
*/
-long hmm_range_fault(struct hmm_range *range, unsigned int flags)
+int hmm_range_fault(struct hmm_range *range)
{
- const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
- unsigned long start = range->start, end;
- struct hmm_vma_walk hmm_vma_walk;
- struct hmm *hmm = range->hmm;
- struct vm_area_struct *vma;
+ struct hmm_vma_walk hmm_vma_walk = {
+ .range = range,
+ .last = range->start,
+ };
+ struct mm_struct *mm = range->notifier->mm;
int ret;
- lockdep_assert_held(&hmm->mmu_notifier.mm->mmap_sem);
+ mmap_assert_locked(mm);
do {
/* If range is no longer valid force retry. */
- if (!range->valid)
+ if (mmu_interval_check_retry(range->notifier,
+ range->notifier_seq))
return -EBUSY;
-
- vma = find_vma(hmm->mmu_notifier.mm, start);
- if (vma == NULL || (vma->vm_flags & device_vma))
- return -EFAULT;
-
- if (!(vma->vm_flags & VM_READ)) {
- /*
- * If vma do not allow read access, then assume that it
- * does not allow write access, either. HMM does not
- * support architecture that allow write without read.
- */
- hmm_pfns_clear(range, range->pfns,
- range->start, range->end);
- return -EPERM;
- }
-
- hmm_vma_walk.pgmap = NULL;
- hmm_vma_walk.last = start;
- hmm_vma_walk.flags = flags;
- hmm_vma_walk.range = range;
- end = min(range->end, vma->vm_end);
-
- walk_page_range(vma->vm_mm, start, end, &hmm_walk_ops,
- &hmm_vma_walk);
-
- do {
- ret = walk_page_range(vma->vm_mm, start, end,
- &hmm_walk_ops, &hmm_vma_walk);
- start = hmm_vma_walk.last;
-
- /* Keep trying while the range is valid. */
- } while (ret == -EBUSY && range->valid);
-
- if (ret) {
- unsigned long i;
-
- i = (hmm_vma_walk.last - range->start) >> PAGE_SHIFT;
- hmm_pfns_clear(range, &range->pfns[i],
- hmm_vma_walk.last, range->end);
- return ret;
- }
- start = end;
-
- } while (start < range->end);
-
- return (hmm_vma_walk.last - range->start) >> PAGE_SHIFT;
-}
-EXPORT_SYMBOL(hmm_range_fault);
-
-/**
- * hmm_range_dma_map - hmm_range_fault() and dma map page all in one.
- * @range: range being faulted
- * @device: device to map page to
- * @daddrs: array of dma addresses for the mapped pages
- * @flags: HMM_FAULT_*
- *
- * Return: the number of pages mapped on success (including zero), or any
- * status return from hmm_range_fault() otherwise.
- */
-long hmm_range_dma_map(struct hmm_range *range, struct device *device,
- dma_addr_t *daddrs, unsigned int flags)
-{
- unsigned long i, npages, mapped;
- long ret;
-
- ret = hmm_range_fault(range, flags);
- if (ret <= 0)
- return ret ? ret : -EBUSY;
-
- npages = (range->end - range->start) >> PAGE_SHIFT;
- for (i = 0, mapped = 0; i < npages; ++i) {
- enum dma_data_direction dir = DMA_TO_DEVICE;
- struct page *page;
-
+ ret = walk_page_range(mm, hmm_vma_walk.last, range->end,
+ &hmm_walk_ops, &hmm_vma_walk);
/*
- * FIXME need to update DMA API to provide invalid DMA address
- * value instead of a function to test dma address value. This
- * would remove lot of dumb code duplicated accross many arch.
- *
- * For now setting it to 0 here is good enough as the pfns[]
- * value is what is use to check what is valid and what isn't.
+ * When -EBUSY is returned the loop restarts with
+ * hmm_vma_walk.last set to an address that has not been stored
+ * in pfns. All entries < last in the pfn array are set to their
+ * output, and all >= are still at their input values.
*/
- daddrs[i] = 0;
-
- page = hmm_device_entry_to_page(range, range->pfns[i]);
- if (page == NULL)
- continue;
-
- /* Check if range is being invalidated */
- if (!range->valid) {
- ret = -EBUSY;
- goto unmap;
- }
-
- /* If it is read and write than map bi-directional. */
- if (range->pfns[i] & range->flags[HMM_PFN_WRITE])
- dir = DMA_BIDIRECTIONAL;
-
- daddrs[i] = dma_map_page(device, page, 0, PAGE_SIZE, dir);
- if (dma_mapping_error(device, daddrs[i])) {
- ret = -EFAULT;
- goto unmap;
- }
-
- mapped++;
- }
-
- return mapped;
-
-unmap:
- for (npages = i, i = 0; (i < npages) && mapped; ++i) {
- enum dma_data_direction dir = DMA_TO_DEVICE;
- struct page *page;
-
- page = hmm_device_entry_to_page(range, range->pfns[i]);
- if (page == NULL)
- continue;
-
- if (dma_mapping_error(device, daddrs[i]))
- continue;
-
- /* If it is read and write than map bi-directional. */
- if (range->pfns[i] & range->flags[HMM_PFN_WRITE])
- dir = DMA_BIDIRECTIONAL;
-
- dma_unmap_page(device, daddrs[i], PAGE_SIZE, dir);
- mapped--;
- }
-
+ } while (ret == -EBUSY);
return ret;
}
-EXPORT_SYMBOL(hmm_range_dma_map);
-
-/**
- * hmm_range_dma_unmap() - unmap range of that was map with hmm_range_dma_map()
- * @range: range being unmapped
- * @device: device against which dma map was done
- * @daddrs: dma address of mapped pages
- * @dirty: dirty page if it had the write flag set
- * Return: number of page unmapped on success, -EINVAL otherwise
- *
- * Note that caller MUST abide by mmu notifier or use HMM mirror and abide
- * to the sync_cpu_device_pagetables() callback so that it is safe here to
- * call set_page_dirty(). Caller must also take appropriate locks to avoid
- * concurrent mmu notifier or sync_cpu_device_pagetables() to make progress.
- */
-long hmm_range_dma_unmap(struct hmm_range *range,
- struct device *device,
- dma_addr_t *daddrs,
- bool dirty)
-{
- unsigned long i, npages;
- long cpages = 0;
-
- /* Sanity check. */
- if (range->end <= range->start)
- return -EINVAL;
- if (!daddrs)
- return -EINVAL;
- if (!range->pfns)
- return -EINVAL;
-
- npages = (range->end - range->start) >> PAGE_SHIFT;
- for (i = 0; i < npages; ++i) {
- enum dma_data_direction dir = DMA_TO_DEVICE;
- struct page *page;
-
- page = hmm_device_entry_to_page(range, range->pfns[i]);
- if (page == NULL)
- continue;
-
- /* If it is read and write than map bi-directional. */
- if (range->pfns[i] & range->flags[HMM_PFN_WRITE]) {
- dir = DMA_BIDIRECTIONAL;
-
- /*
- * See comments in function description on why it is
- * safe here to call set_page_dirty()
- */
- if (dirty)
- set_page_dirty(page);
- }
-
- /* Unmap and clear pfns/dma address */
- dma_unmap_page(device, daddrs[i], PAGE_SIZE, dir);
- range->pfns[i] = range->values[HMM_PFN_NONE];
- /* FIXME see comments in hmm_vma_dma_map() */
- daddrs[i] = 0;
- cpages++;
- }
-
- return cpages;
-}
-EXPORT_SYMBOL(hmm_range_dma_unmap);
+EXPORT_SYMBOL(hmm_range_fault);