This code would be a lot more readable if it had fewer goto's.
The goto out's are ok but the again and add_more are easily
eliminated.
Two possibilities...
On 1/12/2023 12:19 PM, Vishal Moola wrote:
On Wed, Jan 4, 2023 at 1:15 PM Vishal Moola (Oracle)
<vishal.moola@xxxxxxxxx> wrote:
This is in preparation for the removal of find_get_pages_range_tag(). Now also
supports the use of large folios.
Since tofind might be larger than the max number of folios in a
folio_batch (15), we loop through filling in wdata->pages pulling more
batches until we either reach tofind pages or run out of folios.
This function may not return all pages in the last found folio before
tofind pages are reached.
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
---
fs/cifs/file.c | 32 +++++++++++++++++++++++++++++---
1 file changed, 29 insertions(+), 3 deletions(-)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 22dfc1f8b4f1..8cdd2f67af24 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2527,14 +2527,40 @@ wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
unsigned int *found_pages)
{
struct cifs_writedata *wdata;
-
+ struct folio_batch fbatch;
+ unsigned int i, idx, p, nr;
wdata = cifs_writedata_alloc((unsigned int)tofind,
cifs_writev_complete);
if (!wdata)
return NULL;
- *found_pages = find_get_pages_range_tag(mapping, index, end,
- PAGECACHE_TAG_DIRTY, tofind, wdata->pages);
+ folio_batch_init(&fbatch);
+ *found_pages = 0;
+
This is really just the top of a while loop:
while (nr = filemap_get_folios_tag(...)) {
+again:
+ nr = filemap_get_folios_tag(mapping, index, end,
+ PAGECACHE_TAG_DIRTY, &fbatch);
+ if (!nr)
+ goto out; /* No dirty pages left in the range */
+
+ for (i = 0; i < nr; i++) {
+ struct folio *folio = fbatch.folios[i];
+
+ idx = 0;
+ p = folio_nr_pages(folio);
And this is a "do {"
+add_more:
+ wdata->pages[*found_pages] = folio_page(folio, idx);
+ folio_get(folio);
+ if (++*found_pages == tofind) {
+ folio_batch_release(&fbatch);
+ goto out;
+ }
+ if (++idx < p)
+ goto add_more;
To here "} while (++idx < p);"
+ }
+ folio_batch_release(&fbatch);
+ goto again;
End while "}"
+out:
return wdata;
}
--
2.38.1
Could someone review this cifs patch, please? This is one of the
2 remaining patches that need to be looked at in the series.
It's otherwise ok.
Tom.
