return rc;
id = dax_read_lock();
- rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(PAGE_SIZE), &kaddr, NULL);
+ rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL);
if (rc < 0) {
dax_read_unlock(id);
return rc;
return (iomap->addr + (pos & PAGE_MASK) - iomap->offset) >> 9;
}
-static int dax_iomap_pfn(struct iomap *iomap, loff_t pos, size_t size,
+static int dax_iomap_pfn(const struct iomap *iomap, loff_t pos, size_t size,
pfn_t *pfnp)
{
const sector_t sector = dax_iomap_sector(iomap, pos);
return ret;
}
+#ifdef CONFIG_FS_DAX_PMD
+static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
+ const struct iomap *iomap, void **entry)
+{
+ 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;
+ pfn_t pfn;
+
+ zero_page = mm_get_huge_zero_page(vmf->vma->vm_mm);
+
+ if (unlikely(!zero_page))
+ goto fallback;
+
+ pfn = page_to_pfn_t(zero_page);
+ *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);
+ spin_unlock(ptl);
+ trace_dax_pmd_load_hole(inode, vmf, zero_page, *entry);
+ 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;
+}
+#else
+static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
+ const struct iomap *iomap, void **entry)
+{
+ return VM_FAULT_FALLBACK;
+}
+#endif /* CONFIG_FS_DAX_PMD */
+
s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
{
sector_t sector = iomap_sector(iomap, pos & PAGE_MASK);
* flushed on write-faults (non-cow), but not read-faults.
*/
static bool dax_fault_is_synchronous(unsigned long flags,
- struct vm_area_struct *vma, struct iomap *iomap)
+ struct vm_area_struct *vma, const struct iomap *iomap)
{
return (flags & IOMAP_WRITE) && (vma->vm_flags & VM_SYNC)
&& (iomap->flags & IOMAP_F_DIRTY);
return VM_FAULT_NEEDDSYNC;
}
-static vm_fault_t dax_fault_cow_page(struct vm_fault *vmf, struct iomap *iomap,
- loff_t pos)
+static vm_fault_t dax_fault_cow_page(struct vm_fault *vmf,
+ const struct iomap_iter *iter)
{
- sector_t sector = dax_iomap_sector(iomap, pos);
+ sector_t sector = dax_iomap_sector(&iter->iomap, iter->pos);
unsigned long vaddr = vmf->address;
vm_fault_t ret;
int error = 0;
- switch (iomap->type) {
+ switch (iter->iomap.type) {
case IOMAP_HOLE:
case IOMAP_UNWRITTEN:
clear_user_highpage(vmf->cow_page, vaddr);
break;
case IOMAP_MAPPED:
- error = copy_cow_page_dax(iomap->bdev, iomap->dax_dev, sector,
- vmf->cow_page, vaddr);
+ error = copy_cow_page_dax(iter->iomap.bdev, iter->iomap.dax_dev,
+ sector, vmf->cow_page, vaddr);
break;
default:
WARN_ON_ONCE(1);
return ret;
}
+/**
+ * dax_fault_iter - Common actor to handle pfn insertion in PTE/PMD fault.
+ * @vmf: vm fault instance
+ * @iter: iomap iter
+ * @pfnp: pfn to be returned
+ * @xas: the dax mapping tree of a file
+ * @entry: an unlocked dax entry to be inserted
+ * @pmd: distinguish whether it is a pmd fault
+ */
+static vm_fault_t dax_fault_iter(struct vm_fault *vmf,
+ const struct iomap_iter *iter, pfn_t *pfnp,
+ struct xa_state *xas, void **entry, bool pmd)
+{
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
+ const struct iomap *iomap = &iter->iomap;
+ size_t size = pmd ? PMD_SIZE : PAGE_SIZE;
+ loff_t pos = (loff_t)xas->xa_index << PAGE_SHIFT;
+ bool write = vmf->flags & FAULT_FLAG_WRITE;
+ bool sync = dax_fault_is_synchronous(iter->flags, vmf->vma, iomap);
+ unsigned long entry_flags = pmd ? DAX_PMD : 0;
+ int err = 0;
+ pfn_t pfn;
+
+ if (!pmd && vmf->cow_page)
+ return dax_fault_cow_page(vmf, iter);
+
+ /* if we are reading UNWRITTEN and HOLE, return a hole. */
+ if (!write &&
+ (iomap->type == IOMAP_UNWRITTEN || iomap->type == IOMAP_HOLE)) {
+ if (!pmd)
+ return dax_load_hole(xas, mapping, entry, vmf);
+ return dax_pmd_load_hole(xas, vmf, iomap, entry);
+ }
+
+ if (iomap->type != IOMAP_MAPPED) {
+ WARN_ON_ONCE(1);
+ return pmd ? VM_FAULT_FALLBACK : VM_FAULT_SIGBUS;
+ }
+
+ err = dax_iomap_pfn(&iter->iomap, pos, size, &pfn);
+ if (err)
+ return pmd ? VM_FAULT_FALLBACK : dax_fault_return(err);
+
+ *entry = dax_insert_entry(xas, mapping, vmf, *entry, pfn, entry_flags,
+ write && !sync);
+
+ if (sync)
+ return dax_fault_synchronous_pfnp(pfnp, pfn);
+
+ /* insert PMD pfn */
+ if (pmd)
+ return vmf_insert_pfn_pmd(vmf, pfn, write);
+
+ /* insert PTE pfn */
+ if (write)
+ return vmf_insert_mixed_mkwrite(vmf->vma, vmf->address, pfn);
+ return vmf_insert_mixed(vmf->vma, vmf->address, pfn);
+}
+
static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
int *iomap_errp, const struct iomap_ops *ops)
{
- struct vm_area_struct *vma = vmf->vma;
- struct address_space *mapping = vma->vm_file->f_mapping;
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
XA_STATE(xas, &mapping->i_pages, vmf->pgoff);
- struct inode *inode = mapping->host;
- unsigned long vaddr = vmf->address;
- loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
- struct iomap iomap = { .type = IOMAP_HOLE };
- struct iomap srcmap = { .type = IOMAP_HOLE };
- unsigned flags = IOMAP_FAULT;
- int error, major = 0;
- bool write = vmf->flags & FAULT_FLAG_WRITE;
- bool sync;
+ struct iomap_iter iter = {
+ .inode = mapping->host,
+ .pos = (loff_t)vmf->pgoff << PAGE_SHIFT,
+ .len = PAGE_SIZE,
+ .flags = IOMAP_FAULT,
+ };
vm_fault_t ret = 0;
void *entry;
- pfn_t pfn;
+ int error;
- trace_dax_pte_fault(inode, vmf, ret);
+ trace_dax_pte_fault(iter.inode, vmf, ret);
/*
* Check whether offset isn't beyond end of file now. Caller is supposed
* to hold locks serializing us with truncate / punch hole so this is
* a reliable test.
*/
- if (pos >= i_size_read(inode)) {
+ if (iter.pos >= i_size_read(iter.inode)) {
ret = VM_FAULT_SIGBUS;
goto out;
}
- if (write && !vmf->cow_page)
- flags |= IOMAP_WRITE;
+ if ((vmf->flags & FAULT_FLAG_WRITE) && !vmf->cow_page)
+ iter.flags |= IOMAP_WRITE;
entry = grab_mapping_entry(&xas, mapping, 0);
if (xa_is_internal(entry)) {
goto unlock_entry;
}
- /*
- * Note that we don't bother to use iomap_iter here: DAX required
- * the file system block size to be equal the page size, which means
- * that we never have to deal with more than a single extent here.
- */
- error = ops->iomap_begin(inode, pos, PAGE_SIZE, flags, &iomap, &srcmap);
- if (iomap_errp)
- *iomap_errp = error;
- if (error) {
- ret = dax_fault_return(error);
- goto unlock_entry;
- }
- if (WARN_ON_ONCE(iomap.offset + iomap.length < pos + PAGE_SIZE)) {
- error = -EIO; /* fs corruption? */
- goto error_finish_iomap;
- }
-
- if (vmf->cow_page) {
- ret = dax_fault_cow_page(vmf, &iomap, pos);
- goto finish_iomap;
- }
-
- sync = dax_fault_is_synchronous(flags, vma, &iomap);
-
- switch (iomap.type) {
- case IOMAP_MAPPED:
- if (iomap.flags & IOMAP_F_NEW) {
- count_vm_event(PGMAJFAULT);
- count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
- major = VM_FAULT_MAJOR;
+ while ((error = iomap_iter(&iter, ops)) > 0) {
+ if (WARN_ON_ONCE(iomap_length(&iter) < PAGE_SIZE)) {
+ iter.processed = -EIO; /* fs corruption? */
+ continue;
}
- error = dax_iomap_pfn(&iomap, pos, PAGE_SIZE, &pfn);
- if (error < 0)
- goto error_finish_iomap;
-
- entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
- 0, write && !sync);
- if (sync) {
- ret = dax_fault_synchronous_pfnp(pfnp, pfn);
- goto finish_iomap;
+ ret = dax_fault_iter(vmf, &iter, pfnp, &xas, &entry, false);
+ if (ret != VM_FAULT_SIGBUS &&
+ (iter.iomap.flags & IOMAP_F_NEW)) {
+ count_vm_event(PGMAJFAULT);
+ count_memcg_event_mm(vmf->vma->vm_mm, PGMAJFAULT);
+ ret |= VM_FAULT_MAJOR;
}
- trace_dax_insert_mapping(inode, vmf, entry);
- if (write)
- ret = vmf_insert_mixed_mkwrite(vma, vaddr, pfn);
- else
- ret = vmf_insert_mixed(vma, vaddr, pfn);
- goto finish_iomap;
- case IOMAP_UNWRITTEN:
- case IOMAP_HOLE:
- if (!write) {
- ret = dax_load_hole(&xas, mapping, &entry, vmf);
- goto finish_iomap;
- }
- fallthrough;
- default:
- WARN_ON_ONCE(1);
- error = -EIO;
- break;
+ if (!(ret & VM_FAULT_ERROR))
+ iter.processed = PAGE_SIZE;
}
- error_finish_iomap:
- ret = dax_fault_return(error);
- finish_iomap:
- if (ops->iomap_end) {
- int copied = PAGE_SIZE;
+ if (iomap_errp)
+ *iomap_errp = error;
+ if (!ret && error)
+ ret = dax_fault_return(error);
- if (ret & VM_FAULT_ERROR)
- copied = 0;
- /*
- * The fault is done by now and there's no way back (other
- * thread may be already happily using PTE we have installed).
- * Just ignore error from ->iomap_end since we cannot do much
- * with it.
- */
- ops->iomap_end(inode, pos, PAGE_SIZE, copied, flags, &iomap);
- }
- unlock_entry:
+unlock_entry:
dax_unlock_entry(&xas, entry);
- out:
- trace_dax_pte_fault_done(inode, vmf, ret);
- return ret | major;
+out:
+ trace_dax_pte_fault_done(iter.inode, vmf, ret);
+ return ret;
}
#ifdef CONFIG_FS_DAX_PMD
-static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
- struct iomap *iomap, void **entry)
-{
- 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;
- pfn_t pfn;
-
- zero_page = mm_get_huge_zero_page(vmf->vma->vm_mm);
-
- if (unlikely(!zero_page))
- goto fallback;
-
- pfn = page_to_pfn_t(zero_page);
- *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);
- spin_unlock(ptl);
- trace_dax_pmd_load_hole(inode, vmf, zero_page, *entry);
- 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;
-}
-
static bool dax_fault_check_fallback(struct vm_fault *vmf, struct xa_state *xas,
pgoff_t max_pgoff)
{
static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
const struct iomap_ops *ops)
{
- struct vm_area_struct *vma = vmf->vma;
- struct address_space *mapping = vma->vm_file->f_mapping;
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
XA_STATE_ORDER(xas, &mapping->i_pages, vmf->pgoff, PMD_ORDER);
- bool write = vmf->flags & FAULT_FLAG_WRITE;
- bool sync;
- unsigned int iomap_flags = (write ? IOMAP_WRITE : 0) | IOMAP_FAULT;
- struct inode *inode = mapping->host;
- vm_fault_t result = VM_FAULT_FALLBACK;
- struct iomap iomap = { .type = IOMAP_HOLE };
- struct iomap srcmap = { .type = IOMAP_HOLE };
+ struct iomap_iter iter = {
+ .inode = mapping->host,
+ .len = PMD_SIZE,
+ .flags = IOMAP_FAULT,
+ };
+ vm_fault_t ret = VM_FAULT_FALLBACK;
pgoff_t max_pgoff;
void *entry;
- loff_t pos;
int error;
- pfn_t pfn;
+
+ if (vmf->flags & FAULT_FLAG_WRITE)
+ iter.flags |= IOMAP_WRITE;
/*
* Check whether offset isn't beyond end of file now. Caller is
* supposed to hold locks serializing us with truncate / punch hole so
* this is a reliable test.
*/
- max_pgoff = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ max_pgoff = DIV_ROUND_UP(i_size_read(iter.inode), PAGE_SIZE);
- trace_dax_pmd_fault(inode, vmf, max_pgoff, 0);
+ trace_dax_pmd_fault(iter.inode, vmf, max_pgoff, 0);
if (xas.xa_index >= max_pgoff) {
- result = VM_FAULT_SIGBUS;
+ ret = VM_FAULT_SIGBUS;
goto out;
}
*/
entry = grab_mapping_entry(&xas, mapping, PMD_ORDER);
if (xa_is_internal(entry)) {
- result = xa_to_internal(entry);
+ ret = xa_to_internal(entry);
goto fallback;
}
*/
if (!pmd_none(*vmf->pmd) && !pmd_trans_huge(*vmf->pmd) &&
!pmd_devmap(*vmf->pmd)) {
- result = 0;
+ ret = 0;
goto unlock_entry;
}
- /*
- * Note that we don't use iomap_iter here. We aren't doing I/O, only
- * setting up a mapping, so really we're using iomap_begin() as a way
- * to look up our filesystem block.
- */
- pos = (loff_t)xas.xa_index << PAGE_SHIFT;
- error = ops->iomap_begin(inode, pos, PMD_SIZE, iomap_flags, &iomap,
- &srcmap);
- if (error)
- goto unlock_entry;
+ iter.pos = (loff_t)xas.xa_index << PAGE_SHIFT;
+ while ((error = iomap_iter(&iter, ops)) > 0) {
+ if (iomap_length(&iter) < PMD_SIZE)
+ continue; /* actually breaks out of the loop */
- if (iomap.offset + iomap.length < pos + PMD_SIZE)
- goto finish_iomap;
-
- sync = dax_fault_is_synchronous(iomap_flags, vma, &iomap);
-
- switch (iomap.type) {
- case IOMAP_MAPPED:
- error = dax_iomap_pfn(&iomap, pos, PMD_SIZE, &pfn);
- if (error < 0)
- goto finish_iomap;
-
- entry = dax_insert_entry(&xas, mapping, vmf, entry, pfn,
- DAX_PMD, write && !sync);
-
- if (sync) {
- result = dax_fault_synchronous_pfnp(pfnp, pfn);
- goto finish_iomap;
- }
-
- trace_dax_pmd_insert_mapping(inode, vmf, PMD_SIZE, pfn, entry);
- result = vmf_insert_pfn_pmd(vmf, pfn, write);
- break;
- case IOMAP_UNWRITTEN:
- case IOMAP_HOLE:
- if (WARN_ON_ONCE(write))
- break;
- result = dax_pmd_load_hole(&xas, vmf, &iomap, &entry);
- break;
- default:
- WARN_ON_ONCE(1);
- break;
+ ret = dax_fault_iter(vmf, &iter, pfnp, &xas, &entry, true);
+ if (ret != VM_FAULT_FALLBACK)
+ iter.processed = PMD_SIZE;
}
- finish_iomap:
- if (ops->iomap_end) {
- int copied = PMD_SIZE;
-
- if (result == VM_FAULT_FALLBACK)
- copied = 0;
- /*
- * The fault is done by now and there's no way back (other
- * thread may be already happily using PMD we have installed).
- * Just ignore error from ->iomap_end since we cannot do much
- * with it.
- */
- ops->iomap_end(inode, pos, PMD_SIZE, copied, iomap_flags,
- &iomap);
- }
- unlock_entry:
+unlock_entry:
dax_unlock_entry(&xas, entry);
- fallback:
- if (result == VM_FAULT_FALLBACK) {
- split_huge_pmd(vma, vmf->pmd, vmf->address);
+fallback:
+ if (ret == VM_FAULT_FALLBACK) {
+ split_huge_pmd(vmf->vma, vmf->pmd, vmf->address);
count_vm_event(THP_FAULT_FALLBACK);
}
out:
- trace_dax_pmd_fault_done(inode, vmf, max_pgoff, result);
- return result;
+ trace_dax_pmd_fault_done(iter.inode, vmf, max_pgoff, ret);
+ return ret;
}
#else
static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
projects / linux-2.6-microblaze.git / blobdiff