This is the last remaining user of the multiorder functionality of the
radix tree.  Test the XArray instead.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

In preparation for the removal of the multiorder radix tree code,
convert item_delete_rcu() to use the XArray so it can still be called
for XArrays containing multi-index entries.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

In preparation for the removal of the multiorder radix tree code,
convert item_kill_tree() to use the XArray so it can still be called
for XArrays containing multi-index entries.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The remaining tests are not suitable for moving in-kernel, so move
item_insert_order() into multiorder.c, make it static and make it use
the XArray.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The multiorder radix tree code is being removed, so remove the
benchmarking of its performance.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Inline it into its one caller
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Use the new xa_store_range function instead of the radix tree.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This version of xa_store_range() really only supports load and store.
Our only user only needs basic load and store functionality, so there's
no need to do the extra work to support marking and overlapping stores
correctly yet.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This version is a little less thorough in order to be a little quicker,
but tests the important edge cases.  Also test adding a multiorder entry
at a non-canonical index, and erasing it.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Test this functionality inside the kernel as well as in userspace.
Also remove insert_bug() as there's no comparable thing to test
in the XArray code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Move this test to the in-kernel test suite, and enhance it to test
several different orders.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

With no code left in the kernel using the multiorder radix tree, convert
the iteration test from the radix tree to the XArray.  It's unlikely to
suffer the same bug as the radix tree, but this test will prevent that
bug from ever creeping into the XArray implementation.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The tag_tagged_items() function is supposed to test the page-writeback
tagging code.  Since that has been converted to the XArray, there's
not much point in testing the radix tree's tagging code.  This requires
using the pthread mutex embedded in the xarray instead of an external
lock, so remove the pthread mutexes which protect xarrays/radix trees.
Also remove radix_tree_iter_tag_set() as this was the last user.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The page cache was the only user of this interface and it has now
been converted to the XArray.  Transform the test into a test of
xas_init_marks().
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This function was only used by the page cache which is now converted
to the XArray.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

radix_tree_split and radix_tree_join were never used upstream.  Remove
them; if they're needed in future they will be replaced by XArray
equivalents.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

The only user of this functionality was the workingset code, and it's
now been converted to the XArray.  Remove __radix_tree_delete_node()
entirely as it was also only used by the workingset code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

With no more radix tree API users left, we can drop the GFP flags
and use xa_init() instead of INIT_RADIX_TREE().
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This is the last part of DAX to be converted to the XArray so
remove all the old helper functions.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Instead of always retrying when we slept, only retry if the page has
moved.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Use XArray iteration instead of a pagevec.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Avoids walking the radix tree multiple times looking for tags.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Instead of using a pagevec, just use the XArray iterators.  Add a
conditional rescheduling point which probably should have been there in
the original.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Add some XArray-based helper functions to replace the radix tree based
metaphors currently in use.  The biggest change is that converted code
doesn't see its own lock bit; get_unlocked_entry() always returns an
entry with the lock bit clear.  So we don't have to mess around loading
the current entry and clearing the lock bit; we can just store the
unlocked entry that we already have.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Since the XArray is embedded in the struct address_space, its address
contains exactly as much entropy as the address of the mapping.  This
patch is purely preparatory for later patches which will simplify the
wait/wake interfaces.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Remove mentions of 'radix' and 'radix tree'.  Simplify some names by
dropping the word 'mapping'.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This is a straightforward conversion.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This is close to a 1:1 replacement of radix tree APIs with their XArray
equivalents.  It would be possible to optimise nilfs_copy_back_pages(),
but that doesn't seem to be in the performance path.  Also, I think
it has a pre-existing bug, and I've added a note to that effect in the
source code.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

A couple of short loops.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Mostly comment fixes, but one use of __xa_set_mark.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: David Sterba <dsterba@suse.com>

Remove the last mentions of radix tree from various comments.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Switch to a batch-processing model like memfd_wait_for_pins() and
use the xa_state previously set up by memfd_wait_for_pins().
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

Simplify the locking by taking the spinlock while we walk the tree on
the assumption that many acquires and releases of the lock will be worse
than holding the lock while we process an entire batch of pages.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>

Simpler code because the xarray takes care of things like the limit and
dereferencing the slot.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

Since we are conditionally storing NULL in the XArray, we do not need
to allocate memory and the GFP flags will be unused.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

xa_find() is a slightly easier API to use than
radix_tree_gang_lookup_slot() because it contains its own RCU locking.
This commit removes the last user of radix_tree_gang_lookup_slot()
so remove the function too.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

We can use xas_find_conflict() instead of radix_tree_gang_lookup_slot()
to find any conflicting entry and combine the three paths through this
function into one.
Signed-off-by: Matthew Wilcox <willy@infradead.org>

This is a 1:1 conversion.  The major part of this patch is converting
the test framework from userspace to kernel space and mirroring the
algorithm now used in find_swap_entry().
Signed-off-by: Matthew Wilcox <willy@infradead.org>

xa_load has its own RCU locking, so we can eliminate it here.
Signed-off-by: Matthew Wilcox <willy@infradead.org>