iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop,
loff_t *pos, loff_t length, unsigned *offp, unsigned *lenp)
{
+ loff_t orig_pos = *pos;
+ loff_t isize = i_size_read(inode);
unsigned block_bits = inode->i_blkbits;
unsigned block_size = (1 << block_bits);
unsigned poff = offset_in_page(*pos);
unsigned plen = min_t(loff_t, PAGE_SIZE - poff, length);
unsigned first = poff >> block_bits;
unsigned last = (poff + plen - 1) >> block_bits;
- unsigned end = offset_in_page(i_size_read(inode)) >> block_bits;
/*
* If the block size is smaller than the page size we need to check the
* handle both halves separately so that we properly zero data in the
* page cache for blocks that are entirely outside of i_size.
*/
- if (first <= end && last > end)
- plen -= (last - end) * block_size;
+ if (orig_pos <= isize && orig_pos + length > isize) {
+ unsigned end = offset_in_page(isize - 1) >> block_bits;
+
+ if (first <= end && last > end)
+ plen -= (last - end) * block_size;
+ }
*offp = poff;
*lenp = plen;
}
EXPORT_SYMBOL_GPL(iomap_readpages);
+/*
+ * iomap_is_partially_uptodate checks whether blocks within a page are
+ * uptodate or not.
+ *
+ * Returns true if all blocks which correspond to a file portion
+ * we want to read within the page are uptodate.
+ */
int
iomap_is_partially_uptodate(struct page *page, unsigned long from,
unsigned long count)
{
struct iomap_page *iop = to_iomap_page(page);
struct inode *inode = page->mapping->host;
- unsigned first = from >> inode->i_blkbits;
- unsigned last = (from + count - 1) >> inode->i_blkbits;
+ unsigned len, first, last;
unsigned i;
+ /* Limit range to one page */
+ len = min_t(unsigned, PAGE_SIZE - from, count);
+
+ /* First and last blocks in range within page */
+ first = from >> inode->i_blkbits;
+ last = (from + len - 1) >> inode->i_blkbits;
+
if (iop) {
for (i = first; i <= last; i++)
if (!test_bit(i, iop->uptodate))
{
int ret;
- ret = migrate_page_move_mapping(mapping, newpage, page, NULL, mode, 0);
+ ret = migrate_page_move_mapping(mapping, newpage, page, mode, 0);
if (ret != MIGRATEPAGE_SUCCESS)
return ret;
if (dio->wait_for_completion) {
struct task_struct *waiter = dio->submit.waiter;
WRITE_ONCE(dio->submit.waiter, NULL);
- wake_up_process(waiter);
+ blk_wake_io_task(waiter);
} else if (dio->flags & IOMAP_DIO_WRITE) {
struct inode *inode = file_inode(dio->iocb->ki_filp);
unsigned len)
{
struct page *page = ZERO_PAGE(0);
+ int flags = REQ_SYNC | REQ_IDLE;
struct bio *bio;
bio = bio_alloc(GFP_KERNEL, 1);
bio->bi_private = dio;
bio->bi_end_io = iomap_dio_bio_end_io;
+ if (dio->iocb->ki_flags & IOCB_HIPRI)
+ flags |= REQ_HIPRI;
+
get_page(page);
__bio_add_page(bio, page, len, 0);
- bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC | REQ_IDLE);
+ bio_set_op_attrs(bio, REQ_OP_WRITE, flags);
atomic_inc(&dio->ref);
return submit_bio(bio);
struct bio *bio;
bool need_zeroout = false;
bool use_fua = false;
- int nr_pages, ret;
+ int nr_pages, ret = 0;
size_t copied = 0;
if ((pos | length | align) & ((1 << blkbits) - 1))
if (iomap->flags & IOMAP_F_NEW) {
need_zeroout = true;
- } else {
+ } else if (iomap->type == IOMAP_MAPPED) {
/*
- * Use a FUA write if we need datasync semantics, this
- * is a pure data IO that doesn't require any metadata
- * updates and the underlying device supports FUA. This
- * allows us to avoid cache flushes on IO completion.
+ * Use a FUA write if we need datasync semantics, this is a pure
+ * data IO that doesn't require any metadata updates (including
+ * after IO completion such as unwritten extent conversion) and
+ * the underlying device supports FUA. This allows us to avoid
+ * cache flushes on IO completion.
*/
if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) &&
(dio->flags & IOMAP_DIO_WRITE_FUA) &&
ret = bio_iov_iter_get_pages(bio, &iter);
if (unlikely(ret)) {
+ /*
+ * We have to stop part way through an IO. We must fall
+ * through to the sub-block tail zeroing here, otherwise
+ * this short IO may expose stale data in the tail of
+ * the block we haven't written data to.
+ */
bio_put(bio);
- return copied ? copied : ret;
+ goto zero_tail;
}
n = bio->bi_iter.bi_size;
bio_set_pages_dirty(bio);
}
+ if (dio->iocb->ki_flags & IOCB_HIPRI)
+ bio->bi_opf |= REQ_HIPRI;
+
iov_iter_advance(dio->submit.iter, n);
dio->size += n;
dio->submit.cookie = submit_bio(bio);
} while (nr_pages);
- if (need_zeroout) {
+ /*
+ * We need to zeroout the tail of a sub-block write if the extent type
+ * requires zeroing or the write extends beyond EOF. If we don't zero
+ * the block tail in the latter case, we can expose stale data via mmap
+ * reads of the EOF block.
+ */
+zero_tail:
+ if (need_zeroout ||
+ ((dio->flags & IOMAP_DIO_WRITE) && pos >= i_size_read(inode))) {
/* zero out from the end of the write to the end of the block */
pad = pos & (fs_block_size - 1);
if (pad)
iomap_dio_zero(dio, iomap, pos, fs_block_size - pad);
}
- return copied;
+ return copied ? copied : ret;
}
static loff_t
if (!(iocb->ki_flags & IOCB_HIPRI) ||
!dio->submit.last_queue ||
!blk_poll(dio->submit.last_queue,
- dio->submit.cookie))
+ dio->submit.cookie, true))
io_schedule();
}
__set_current_state(TASK_RUNNING);
projects / linux-2.6-microblaze.git / blobdiff