The patch titled
Subject: fuse: convert direct IO paths to use FOLL_PIN
has been added to the -mm mm-unstable branch. Its filename is
fuse-convert-direct-io-paths-to-use-foll_pin.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fuse-convert-direct-io-paths-to-use-foll_pin.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: John Hubbard <jhubbard@xxxxxxxxxx>
Subject: fuse: convert direct IO paths to use FOLL_PIN
Date: Tue, 30 Aug 2022 21:18:43 -0700
Convert the fuse filesystem to use pin_user_pages_fast() and
unpin_user_page(), instead of get_user_pages_fast() and put_page().
The user of pin_user_pages_fast() depends upon:
1) CONFIG_BLK_USE_PIN_USER_PAGES_FOR_DIO, and
2) User-space-backed pages or ITER_BVEC pages.
Link: https://lkml.kernel.org/r/20220831041843.973026-8-jhubbard@xxxxxxxxxx
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Anna Schumaker <anna@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Darrick J. Wong <djwong@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Cc: Miklos Szeredi <miklos@xxxxxxxxxx>
Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/fuse/dev.c | 11 +++++++++--
fs/fuse/file.c | 32 +++++++++++++++++++++-----------
fs/fuse/fuse_i.h | 1 +
3 files changed, 31 insertions(+), 13 deletions(-)
--- a/fs/fuse/dev.c~fuse-convert-direct-io-paths-to-use-foll_pin
+++ a/fs/fuse/dev.c
@@ -675,7 +675,12 @@ static void fuse_copy_finish(struct fuse
flush_dcache_page(cs->pg);
set_page_dirty_lock(cs->pg);
}
- put_page(cs->pg);
+ if (!cs->pipebufs &&
+ (user_backed_iter(cs->iter) || iov_iter_is_bvec(cs->iter)))
+ dio_w_unpin_user_page(cs->pg);
+
+ else
+ put_page(cs->pg);
}
cs->pg = NULL;
}
@@ -730,7 +735,9 @@ static int fuse_copy_fill(struct fuse_co
}
} else {
size_t off;
- err = iov_iter_get_pages2(cs->iter, &page, PAGE_SIZE, 1, &off);
+
+ err = dio_w_iov_iter_pin_pages(cs->iter, &page, PAGE_SIZE, 1,
+ &off);
if (err < 0)
return err;
BUG_ON(!err);
--- a/fs/fuse/file.c~fuse-convert-direct-io-paths-to-use-foll_pin
+++ a/fs/fuse/file.c
@@ -625,14 +625,19 @@ void fuse_read_args_fill(struct fuse_io_
}
static void fuse_release_user_pages(struct fuse_args_pages *ap,
- bool should_dirty)
+ bool should_dirty, bool is_user_or_bvec)
{
unsigned int i;
- for (i = 0; i < ap->num_pages; i++) {
- if (should_dirty)
- set_page_dirty_lock(ap->pages[i]);
- put_page(ap->pages[i]);
+ if (is_user_or_bvec) {
+ dio_w_unpin_user_pages_dirty_lock(ap->pages, ap->num_pages,
+ should_dirty);
+ } else {
+ for (i = 0; i < ap->num_pages; i++) {
+ if (should_dirty)
+ set_page_dirty_lock(ap->pages[i]);
+ put_page(ap->pages[i]);
+ }
}
}
@@ -733,7 +738,7 @@ static void fuse_aio_complete_req(struct
struct fuse_io_priv *io = ia->io;
ssize_t pos = -1;
- fuse_release_user_pages(&ia->ap, io->should_dirty);
+ fuse_release_user_pages(&ia->ap, io->should_dirty, io->is_user_or_bvec);
if (err) {
/* Nothing */
@@ -1414,10 +1419,10 @@ static int fuse_get_user_pages(struct fu
while (nbytes < *nbytesp && ap->num_pages < max_pages) {
unsigned npages;
size_t start;
- ret = iov_iter_get_pages2(ii, &ap->pages[ap->num_pages],
- *nbytesp - nbytes,
- max_pages - ap->num_pages,
- &start);
+ ret = dio_w_iov_iter_pin_pages(ii, &ap->pages[ap->num_pages],
+ *nbytesp - nbytes,
+ max_pages - ap->num_pages,
+ &start);
if (ret < 0)
break;
@@ -1483,6 +1488,10 @@ ssize_t fuse_direct_io(struct fuse_io_pr
fl_owner_t owner = current->files;
size_t nbytes = min(count, nmax);
+ /* For use in fuse_release_user_pages(): */
+ io->is_user_or_bvec = user_backed_iter(iter) ||
+ iov_iter_is_bvec(iter);
+
err = fuse_get_user_pages(&ia->ap, iter, &nbytes, write,
max_pages);
if (err && !nbytes)
@@ -1498,7 +1507,8 @@ ssize_t fuse_direct_io(struct fuse_io_pr
}
if (!io->async || nres < 0) {
- fuse_release_user_pages(&ia->ap, io->should_dirty);
+ fuse_release_user_pages(&ia->ap, io->should_dirty,
+ io->is_user_or_bvec);
fuse_io_free(ia);
}
ia = NULL;
--- a/fs/fuse/fuse_i.h~fuse-convert-direct-io-paths-to-use-foll_pin
+++ a/fs/fuse/fuse_i.h
@@ -290,6 +290,7 @@ struct fuse_io_priv {
struct kiocb *iocb;
struct completion *done;
bool blocking;
+ bool is_user_or_bvec;
};
#define FUSE_IO_PRIV_SYNC(i) \
_
Patches currently in -mm which might be from jhubbard@xxxxxxxxxx are
mm-change-release_pages-to-use-unsigned-long-for-npages.patch
mm-gup-introduce-pin_user_page.patch
block-add-dio_w_-wrappers-for-pin-unpin-user-pages.patch
iov_iter-new-iov_iter_pin_pages-routines.patch
block-bio-fs-convert-most-filesystems-to-pin_user_pages_fast.patch
nfs-direct-io-convert-to-foll_pin-pages.patch
fuse-convert-direct-io-paths-to-use-foll_pin.patch
