The nobh mode is an obscure feature to save lowlevel for large memory
32-bit configurations while trading for much slower performance and
has been long obsolete.  Switch to the regular buffer head based helpers
instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

The nobh mode is an obscure feature to save lowlevel for large memory
32-bit configurations while trading for much slower performance and
has been long obsolete.  Remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Handle the resident case with an explicit generic_writepages call instead
of using the obscure overload that makes mpage_writepages with a NULL
get_block do the same thing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

migrate_page_move_mapping(), migrate_page_copy() and migrate_page_states()
are all now unused after converting all the filesystems from
aops->migratepage() to aops->migrate_folio().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

With all users converted to migrate_folio(), remove this operation.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

This is little more than changing the types over; there's no real work
being done in this function.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

This involves converting migrate_huge_page_move_mapping().  We also need a
folio variant of hugetlb_set_page_subpool(), but that's for a later patch.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

Use a folio throughout this function.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

filemap_migrate_folio() fits f2fs's needs perfectly.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Chao Yu <chao@kernel.org>

filemap_migrate_folio() is a little more general than ubifs really needs,
but it's better to share the code.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Use filemap_migrate_folio() to do the bulk of the work, and then copy
the ordered flag across if needed.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>

There is nothing iomap-specific about iomap_migratepage(), and it fits
a pattern used by several other filesystems, so move it to mm/migrate.c,
convert it to be filemap_migrate_folio() and convert the iomap filesystems
to use it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

Convert all callers to pass a folio.  Most have the folio
already available.  Switch all users from aops->migratepage to
aops->migrate_folio.  Also turn the documentation into kerneldoc.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>

Use a folio throughout this function.  migrate_page() will be converted
later.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Use a folio throughout this function.  migrate_page() will be converted
later.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>

Now that both callers have a folio, convert this function to
take a folio & rename it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Use a folio throughout __buffer_migrate_folio(), add kernel-doc for
buffer_migrate_folio() and buffer_migrate_folio_norefs(), move their
declarations to buffer.h and switch all filesystems that have wired
them up.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Use a folio throughout this function.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Use a folio throughout.  migrate_page() will be converted to
migrate_folio() later.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Provide a folio-based replacement for aops->migratepage.  Update the
documentation to document migrate_folio instead of migratepage.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

These drivers are rather uncomfortably hammered into the
address_space_operations hole.  They aren't filesystems and don't behave
like filesystems.  They just need their own movable_operations structure,
which we can point to directly from page->mapping.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

The isolate_page operation is never called for filesystems, only
for device drivers which call SetPageMovable.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>

Remove a call to read_mapping_page().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Use folio_put_refs() to perform only one atomic operation instead of two.
The other changes are straightforward conversions from page APIs to
their folio equivalents.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Use the folio API throughout.  There are a few places where we convert
back to a page to call into the rest of the filesystem, so folio usage
needs to be pushed down to those functions later.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Reorganise the file to remove the forward declaration.
Use folios throughout vxfs_immed_read_folio().
Use memcpy_to_page() instead of an open-coded kmap()/kunmap().
Remove flush_dcache_page() as this is embedded in memcpy_to_page().
Use folio_pos() instead of opencoding it.
Handle multi-page folios.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

This is a straightforward conversion from the page APIs to the folio
APIs.  Symlinks are not allowed to be larger than PAGE_SIZE, so there
is little work to do here.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

This is a straightforward conversion from the page APIs to the folio
APIs.  Symlinks are not allowed to be larger than PAGE_SIZE, so there
is little work to do here.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

This relatively straightforward converion saves a call to compound_head()
hidden inside put_page().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

The bare use of '9' confuses some people.  We also don't need this cast,
since the compiler does exactly that cast for us.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Set p->v to NULL if we try to read beyond the end of the disk, just like
we do if we get an error returned from trying to read the disk.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

That rather complicated expression is just trying to find the offset
of this sector within a page, and there are easier ways to express that.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Since commit 67f9fd91, the code to wait for the read to complete has
been dead.  That commit wrongly stated that the read was synchronous
already; this seems to have been a confusion about which ->readpage
operation was being called.  Instead of reintroducing an asynchronous
version of read_mapping_page(), call the readahead code directly to
submit all reads first before waiting for them in read_mapping_page().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Remove the open-coding of filemap_fdatawait_range().
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

If a page can't be written back, we need to call mapping_set_error(),
not clear the page's Uptodate flag.  Also remove the clearing of PageError
on success; that flag is used for read errors, not write errors.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Since we actually know what error happened, we can report it instead
of having the generic code return -EIO for pages that were unlocked
without being marked uptodate.  Also remove a test of PageError since
we have the return value at this point.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

We can cache this information in a local variable instead of communicating
from one part of the function to another via folio flags.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

The pagecache handles readpage failing by itself; it doesn't want
filesystems to remove pages from under it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

If a buffer is completed with an error, its uptodate flag will be clear,
so the page_uptodate variable will have been set to 0.  There's no
need to check PageError here.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

The page cache clears the error bit before calling ->read_folio(),
so this condition could never have been true.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>