[PATCH RFC PKS/PMEM 32/58] fs/hostfs: Utilize new kmap_thread()

From: ira . weiny
Date: Fri Oct 09 2020 - 16:03:26 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

The kmap() calls in this FS are localized to a single thread. To avoid
the over head of global PKRS updates use the new kmap_thread() call.

Cc: Jeff Dike <jdike@xxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
---
fs/hostfs/hostfs_kern.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index c070c0d8e3e9..608efd0f83cb 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -409,7 +409,7 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
if (page->index >= end_index)
count = inode->i_size & (PAGE_SIZE-1);

- buffer = kmap(page);
+ buffer = kmap_thread(page);

err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count);
if (err != count) {
@@ -425,7 +425,7 @@ static int hostfs_writepage(struct page *page, struct writeback_control *wbc)
err = 0;

out:
- kunmap(page);
+ kunmap_thread(page);

unlock_page(page);
return err;
@@ -437,7 +437,7 @@ static int hostfs_readpage(struct file *file, struct page *page)
loff_t start = page_offset(page);
int bytes_read, ret = 0;

- buffer = kmap(page);
+ buffer = kmap_thread(page);
bytes_read = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer,
PAGE_SIZE);
if (bytes_read < 0) {
@@ -454,7 +454,7 @@ static int hostfs_readpage(struct file *file, struct page *page)

out:
flush_dcache_page(page);
- kunmap(page);
+ kunmap_thread(page);
unlock_page(page);
return ret;
}
@@ -480,9 +480,9 @@ static int hostfs_write_end(struct file *file, struct address_space *mapping,
unsigned from = pos & (PAGE_SIZE - 1);
int err;

- buffer = kmap(page);
+ buffer = kmap_thread(page);
err = write_file(FILE_HOSTFS_I(file)->fd, &pos, buffer + from, copied);
- kunmap(page);
+ kunmap_thread(page);

if (!PageUptodate(page) && err == PAGE_SIZE)
SetPageUptodate(page);
--
2.28.0.rc0.12.gb6a658bd00c9