/*
* Return values:
- * true - folio is locked; mmap_lock is still held.
- * false - folio is not locked.
- * mmap_lock has been released (mmap_read_unlock(), unless flags had both
- * FAULT_FLAG_ALLOW_RETRY and FAULT_FLAG_RETRY_NOWAIT set, in
- * which case mmap_lock is still held.
- *
- * If neither ALLOW_RETRY nor KILLABLE are set, will always return true
- * with the folio locked and the mmap_lock unperturbed.
+ * 0 - folio is locked.
+ * non-zero - folio is not locked.
+ * mmap_lock or per-VMA lock has been released (mmap_read_unlock() or
+ * vma_end_read()), unless flags had both FAULT_FLAG_ALLOW_RETRY and
+ * FAULT_FLAG_RETRY_NOWAIT set, in which case the lock is still held.
+ *
+ * If neither ALLOW_RETRY nor KILLABLE are set, will always return 0
+ * with the folio locked and the mmap_lock/per-VMA lock is left unperturbed.
*/
-bool __folio_lock_or_retry(struct folio *folio, struct mm_struct *mm,
- unsigned int flags)
+vm_fault_t __folio_lock_or_retry(struct folio *folio, struct vm_fault *vmf)
{
+ unsigned int flags = vmf->flags;
+
if (fault_flag_allow_retry_first(flags)) {
/*
- * CAUTION! In this case, mmap_lock is not released
- * even though return 0.
+ * CAUTION! In this case, mmap_lock/per-VMA lock is not
+ * released even though returning VM_FAULT_RETRY.
*/
if (flags & FAULT_FLAG_RETRY_NOWAIT)
- return false;
+ return VM_FAULT_RETRY;
- mmap_read_unlock(mm);
+ release_fault_lock(vmf);
if (flags & FAULT_FLAG_KILLABLE)
folio_wait_locked_killable(folio);
else
folio_wait_locked(folio);
- return false;
+ return VM_FAULT_RETRY;
}
if (flags & FAULT_FLAG_KILLABLE) {
bool ret;
ret = __folio_lock_killable(folio);
if (ret) {
- mmap_read_unlock(mm);
- return false;
+ release_fault_lock(vmf);
+ return VM_FAULT_RETRY;
}
} else {
__folio_lock(folio);
}
- return true;
+ return 0;
}
/**
if (!xa_is_value(folio)) {
if (folio->index < *start)
goto put;
- if (folio->index + folio_nr_pages(folio) - 1 > end)
+ if (folio_next_index(folio) - 1 > end)
goto put;
if (!folio_trylock(folio))
goto put;
}
EXPORT_SYMBOL(filemap_get_folios);
-static inline
-bool folio_more_pages(struct folio *folio, pgoff_t index, pgoff_t max)
-{
- if (!folio_test_large(folio) || folio_test_hugetlb(folio))
- return false;
- if (index >= max)
- return false;
- return index < folio->index + folio_nr_pages(folio) - 1;
-}
-
/**
* filemap_get_folios_contig - Get a batch of contiguous folios
* @mapping: The address_space to search
if (folio_test_hugetlb(folio))
*start = folio->index + 1;
else
- *start = folio->index + folio_nr_pages(folio);
+ *start = folio_next_index(folio);
}
out:
rcu_read_unlock();
break;
if (folio_test_readahead(folio))
break;
- xas_advance(&xas, folio->index + folio_nr_pages(folio) - 1);
+ xas_advance(&xas, folio_next_index(folio) - 1);
continue;
put_folio:
folio_put(folio);
int i, error = 0;
bool writably_mapped;
loff_t isize, end_offset;
+ loff_t last_pos = ra->prev_pos;
if (unlikely(iocb->ki_pos >= inode->i_sb->s_maxbytes))
return 0;
* When a read accesses the same folio several times, only
* mark it as accessed the first time.
*/
- if (!pos_same_folio(iocb->ki_pos, ra->prev_pos - 1,
- fbatch.folios[0]))
+ if (!pos_same_folio(iocb->ki_pos, last_pos - 1,
+ fbatch.folios[0]))
folio_mark_accessed(fbatch.folios[0]);
for (i = 0; i < folio_batch_count(&fbatch); i++) {
already_read += copied;
iocb->ki_pos += copied;
- ra->prev_pos = iocb->ki_pos;
+ last_pos = iocb->ki_pos;
if (copied < bytes) {
error = -EFAULT;
} while (iov_iter_count(iter) && iocb->ki_pos < isize && !error);
file_accessed(filp);
-
+ ra->prev_pos = last_pos;
return already_read ? already_read : error;
}
EXPORT_SYMBOL_GPL(filemap_read);
return false;
}
-static struct folio *next_uptodate_page(struct folio *folio,
- struct address_space *mapping,
- struct xa_state *xas, pgoff_t end_pgoff)
+static struct folio *next_uptodate_folio(struct xa_state *xas,
+ struct address_space *mapping, pgoff_t end_pgoff)
{
+ struct folio *folio = xas_next_entry(xas, end_pgoff);
unsigned long max_idx;
do {
return NULL;
}
-static inline struct folio *first_map_page(struct address_space *mapping,
- struct xa_state *xas,
- pgoff_t end_pgoff)
+/*
+ * Map page range [start_page, start_page + nr_pages) of folio.
+ * start_page is gotten from start by folio_page(folio, start)
+ */
+static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
+ struct folio *folio, unsigned long start,
+ unsigned long addr, unsigned int nr_pages)
{
- return next_uptodate_page(xas_find(xas, end_pgoff),
- mapping, xas, end_pgoff);
-}
+ vm_fault_t ret = 0;
+ struct vm_area_struct *vma = vmf->vma;
+ struct file *file = vma->vm_file;
+ struct page *page = folio_page(folio, start);
+ unsigned int mmap_miss = READ_ONCE(file->f_ra.mmap_miss);
+ unsigned int count = 0;
+ pte_t *old_ptep = vmf->pte;
-static inline struct folio *next_map_page(struct address_space *mapping,
- struct xa_state *xas,
- pgoff_t end_pgoff)
-{
- return next_uptodate_page(xas_next_entry(xas, end_pgoff),
- mapping, xas, end_pgoff);
+ do {
+ if (PageHWPoison(page + count))
+ goto skip;
+
+ if (mmap_miss > 0)
+ mmap_miss--;
+
+ /*
+ * NOTE: If there're PTE markers, we'll leave them to be
+ * handled in the specific fault path, and it'll prohibit the
+ * fault-around logic.
+ */
+ if (!pte_none(vmf->pte[count]))
+ goto skip;
+
+ count++;
+ continue;
+skip:
+ if (count) {
+ set_pte_range(vmf, folio, page, count, addr);
+ folio_ref_add(folio, count);
+ if (in_range(vmf->address, addr, count))
+ ret = VM_FAULT_NOPAGE;
+ }
+
+ count++;
+ page += count;
+ vmf->pte += count;
+ addr += count * PAGE_SIZE;
+ count = 0;
+ } while (--nr_pages > 0);
+
+ if (count) {
+ set_pte_range(vmf, folio, page, count, addr);
+ folio_ref_add(folio, count);
+ if (in_range(vmf->address, addr, count))
+ ret = VM_FAULT_NOPAGE;
+ }
+
+ vmf->pte = old_ptep;
+ WRITE_ONCE(file->f_ra.mmap_miss, mmap_miss);
+
+ return ret;
}
vm_fault_t filemap_map_pages(struct vm_fault *vmf,
unsigned long addr;
XA_STATE(xas, &mapping->i_pages, start_pgoff);
struct folio *folio;
- struct page *page;
- unsigned int mmap_miss = READ_ONCE(file->f_ra.mmap_miss);
vm_fault_t ret = 0;
+ int nr_pages = 0;
rcu_read_lock();
- folio = first_map_page(mapping, &xas, end_pgoff);
+ folio = next_uptodate_folio(&xas, mapping, end_pgoff);
if (!folio)
goto out;
goto out;
}
do {
-again:
- page = folio_file_page(folio, xas.xa_index);
- if (PageHWPoison(page))
- goto unlock;
-
- if (mmap_miss > 0)
- mmap_miss--;
+ unsigned long end;
addr += (xas.xa_index - last_pgoff) << PAGE_SHIFT;
vmf->pte += xas.xa_index - last_pgoff;
last_pgoff = xas.xa_index;
+ end = folio->index + folio_nr_pages(folio) - 1;
+ nr_pages = min(end, end_pgoff) - xas.xa_index + 1;
/*
* NOTE: If there're PTE markers, we'll leave them to be
if (!pte_none(ptep_get(vmf->pte)))
goto unlock;
- /* We're about to handle the fault */
- if (vmf->address == addr)
- ret = VM_FAULT_NOPAGE;
+ ret |= filemap_map_folio_range(vmf, folio,
+ xas.xa_index - folio->index, addr, nr_pages);
- do_set_pte(vmf, page, addr);
- /* no need to invalidate: a not-present page won't be cached */
- update_mmu_cache(vma, addr, vmf->pte);
- if (folio_more_pages(folio, xas.xa_index, end_pgoff)) {
- xas.xa_index++;
- folio_ref_inc(folio);
- goto again;
- }
- folio_unlock(folio);
- continue;
unlock:
- if (folio_more_pages(folio, xas.xa_index, end_pgoff)) {
- xas.xa_index++;
- goto again;
- }
folio_unlock(folio);
folio_put(folio);
- } while ((folio = next_map_page(mapping, &xas, end_pgoff)) != NULL);
+ folio = next_uptodate_folio(&xas, mapping, end_pgoff);
+ } while (folio);
pte_unmap_unlock(vmf->pte, vmf->ptl);
out:
rcu_read_unlock();
- WRITE_ONCE(file->f_ra.mmap_miss, mmap_miss);
return ret;
}
EXPORT_SYMBOL(filemap_map_pages);
struct address_space * const mapping = folio->mapping;
BUG_ON(!folio_test_locked(folio));
+ if (!folio_needs_release(folio))
+ return true;
if (folio_test_writeback(folio))
return false;
projects / linux-2.6-microblaze.git / blobdiff