iomap: Fix some typos and bad grammar
Fix some typos and bad grammar in buffered-io.c to make the comments easier to read. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This commit is contained in:
Andreas Gruenbacher
Darrick J. Wong
parent
b405435b41
commit
f1f264b4c1
@ -36,7 +36,7 @@ static inline struct iomap_page *to_iomap_page(struct page *page)
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{
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/*
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* per-block data is stored in the head page. Callers should
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* not be dealing with tail pages (and if they are, they can
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* not be dealing with tail pages, and if they are, they can
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* call thp_head() first.
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*/
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VM_BUG_ON_PGFLAGS(PageTail(page), page);
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@ -98,7 +98,7 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop,
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unsigned last = (poff + plen - 1) >> block_bits;
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/*
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* If the block size is smaller than the page size we need to check the
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* If the block size is smaller than the page size, we need to check the
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* per-block uptodate status and adjust the offset and length if needed
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* to avoid reading in already uptodate ranges.
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*/
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@ -126,7 +126,7 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop,
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}
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/*
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* If the extent spans the block that contains the i_size we need to
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* If the extent spans the block that contains the i_size, we need to
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* handle both halves separately so that we properly zero data in the
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* page cache for blocks that are entirely outside of i_size.
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*/
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@ -301,7 +301,7 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
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done:
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/*
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* Move the caller beyond our range so that it keeps making progress.
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* For that we have to include any leading non-uptodate ranges, but
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* For that, we have to include any leading non-uptodate ranges, but
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* we can skip trailing ones as they will be handled in the next
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* iteration.
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*/
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@ -338,9 +338,9 @@ iomap_readpage(struct page *page, const struct iomap_ops *ops)
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}
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/*
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* Just like mpage_readahead and block_read_full_page we always
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* Just like mpage_readahead and block_read_full_page, we always
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* return 0 and just mark the page as PageError on errors. This
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* should be cleaned up all through the stack eventually.
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* should be cleaned up throughout the stack eventually.
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*/
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return 0;
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}
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@ -461,7 +461,7 @@ iomap_releasepage(struct page *page, gfp_t gfp_mask)
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/*
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* mm accommodates an old ext3 case where clean pages might not have had
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* the dirty bit cleared. Thus, it can send actual dirty pages to
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* ->releasepage() via shrink_active_list(), skip those here.
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* ->releasepage() via shrink_active_list(); skip those here.
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*/
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if (PageDirty(page) || PageWriteback(page))
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return 0;
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@ -476,7 +476,7 @@ iomap_invalidatepage(struct page *page, unsigned int offset, unsigned int len)
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trace_iomap_invalidatepage(page->mapping->host, offset, len);
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/*
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* If we are invalidating the entire page, clear the dirty state from it
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* If we're invalidating the entire page, clear the dirty state from it
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* and release it to avoid unnecessary buildup of the LRU.
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*/
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if (offset == 0 && len == PAGE_SIZE) {
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@ -658,13 +658,13 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len,
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/*
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* The blocks that were entirely written will now be uptodate, so we
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* don't have to worry about a readpage reading them and overwriting a
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* partial write. However if we have encountered a short write and only
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* partial write. However, if we've encountered a short write and only
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* partially written into a block, it will not be marked uptodate, so a
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* readpage might come in and destroy our partial write.
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*
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* Do the simplest thing, and just treat any short write to a non
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* uptodate page as a zero-length write, and force the caller to redo
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* the whole thing.
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* Do the simplest thing and just treat any short write to a
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* non-uptodate page as a zero-length write, and force the caller to
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* redo the whole thing.
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*/
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if (unlikely(copied < len && !PageUptodate(page)))
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return 0;
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@ -752,7 +752,7 @@ again:
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bytes = length;
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/*
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* Bring in the user page that we will copy from _first_.
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* Bring in the user page that we'll copy from _first_.
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* Otherwise there's a nasty deadlock on copying from the
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* same page as we're writing to, without it being marked
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* up-to-date.
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@ -1161,7 +1161,7 @@ static void iomap_writepage_end_bio(struct bio *bio)
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* Submit the final bio for an ioend.
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*
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* If @error is non-zero, it means that we have a situation where some part of
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* the submission process has failed after we have marked paged for writeback
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* the submission process has failed after we've marked pages for writeback
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* and unlocked them. In this situation, we need to fail the bio instead of
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* submitting it. This typically only happens on a filesystem shutdown.
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*/
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@ -1176,7 +1176,7 @@ iomap_submit_ioend(struct iomap_writepage_ctx *wpc, struct iomap_ioend *ioend,
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error = wpc->ops->prepare_ioend(ioend, error);
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if (error) {
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/*
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* If we are failing the IO now, just mark the ioend with an
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* If we're failing the IO now, just mark the ioend with an
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* error and finish it. This will run IO completion immediately
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* as there is only one reference to the ioend at this point in
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* time.
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@ -1218,7 +1218,7 @@ iomap_alloc_ioend(struct inode *inode, struct iomap_writepage_ctx *wpc,
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/*
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* Allocate a new bio, and chain the old bio to the new one.
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*
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* Note that we have to do perform the chaining in this unintuitive order
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* Note that we have to perform the chaining in this unintuitive order
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* so that the bi_private linkage is set up in the right direction for the
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* traversal in iomap_finish_ioend().
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*/
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@ -1257,7 +1257,7 @@ iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t offset,
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/*
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* Test to see if we have an existing ioend structure that we could append to
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* first, otherwise finish off the current ioend and start another.
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* first; otherwise finish off the current ioend and start another.
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*/
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static void
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iomap_add_to_ioend(struct inode *inode, loff_t offset, struct page *page,
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@ -1288,9 +1288,9 @@ iomap_add_to_ioend(struct inode *inode, loff_t offset, struct page *page,
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/*
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* We implement an immediate ioend submission policy here to avoid needing to
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* chain multiple ioends and hence nest mempool allocations which can violate
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* forward progress guarantees we need to provide. The current ioend we are
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* adding blocks to is cached on the writepage context, and if the new block
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* does not append to the cached ioend it will create a new ioend and cache that
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* the forward progress guarantees we need to provide. The current ioend we're
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* adding blocks to is cached in the writepage context, and if the new block
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* doesn't append to the cached ioend, it will create a new ioend and cache that
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* instead.
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*
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* If a new ioend is created and cached, the old ioend is returned and queued
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@ -1352,7 +1352,7 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc,
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if (unlikely(error)) {
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/*
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* Let the filesystem know what portion of the current page
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* failed to map. If the page wasn't been added to ioend, it
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* failed to map. If the page hasn't been added to ioend, it
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* won't be affected by I/O completion and we must unlock it
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* now.
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*/
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@ -1369,7 +1369,7 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc,
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unlock_page(page);
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/*
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* Preserve the original error if there was one, otherwise catch
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* Preserve the original error if there was one; catch
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* submission errors here and propagate into subsequent ioend
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* submissions.
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*/
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@ -1396,8 +1396,8 @@ done:
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/*
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* Write out a dirty page.
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*
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* For delalloc space on the page we need to allocate space and flush it.
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* For unwritten space on the page we need to start the conversion to
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* For delalloc space on the page, we need to allocate space and flush it.
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* For unwritten space on the page, we need to start the conversion to
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* regular allocated space.
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*/
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static int
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@ -1412,7 +1412,7 @@ iomap_do_writepage(struct page *page, struct writeback_control *wbc, void *data)
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trace_iomap_writepage(inode, page_offset(page), PAGE_SIZE);
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/*
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* Refuse to write the page out if we are called from reclaim context.
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* Refuse to write the page out if we're called from reclaim context.
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*
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* This avoids stack overflows when called from deeply used stacks in
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* random callers for direct reclaim or memcg reclaim. We explicitly
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@ -1457,20 +1457,20 @@ iomap_do_writepage(struct page *page, struct writeback_control *wbc, void *data)
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unsigned offset_into_page = offset & (PAGE_SIZE - 1);
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/*
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* Skip the page if it is fully outside i_size, e.g. due to a
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* truncate operation that is in progress. We must redirty the
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* Skip the page if it's fully outside i_size, e.g. due to a
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* truncate operation that's in progress. We must redirty the
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* page so that reclaim stops reclaiming it. Otherwise
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* iomap_vm_releasepage() is called on it and gets confused.
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*
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* Note that the end_index is unsigned long, it would overflow
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* if the given offset is greater than 16TB on 32-bit system
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* and if we do check the page is fully outside i_size or not
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* via "if (page->index >= end_index + 1)" as "end_index + 1"
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* will be evaluated to 0. Hence this page will be redirtied
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* and be written out repeatedly which would result in an
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* infinite loop, the user program that perform this operation
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* will hang. Instead, we can verify this situation by checking
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* if the page to write is totally beyond the i_size or if it's
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* Note that the end_index is unsigned long. If the given
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* offset is greater than 16TB on a 32-bit system then if we
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* checked if the page is fully outside i_size with
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* "if (page->index >= end_index + 1)", "end_index + 1" would
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* overflow and evaluate to 0. Hence this page would be
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* redirtied and written out repeatedly, which would result in
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* an infinite loop; the user program performing this operation
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* would hang. Instead, we can detect this situation by
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* checking if the page is totally beyond i_size or if its
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* offset is just equal to the EOF.
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*/
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if (page->index > end_index ||
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