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-rw-r--r--fs/fuse/dev.c151
-rw-r--r--fs/fuse/file.c28
-rw-r--r--fs/fuse/fuse_i.h3
3 files changed, 167 insertions, 15 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 2795045..b070d3a 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -17,6 +17,8 @@
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/pipe_fs_i.h>
+#include <linux/swap.h>
+#include <linux/splice.h>
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
@@ -509,6 +511,7 @@ struct fuse_copy_state {
void *mapaddr;
void *buf;
unsigned len;
+ unsigned move_pages:1;
};
static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
@@ -609,13 +612,135 @@ static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
return ncpy;
}
+static int fuse_check_page(struct page *page)
+{
+ if (page_mapcount(page) ||
+ page->mapping != NULL ||
+ page_count(page) != 1 ||
+ (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
+ ~(1 << PG_locked |
+ 1 << PG_referenced |
+ 1 << PG_uptodate |
+ 1 << PG_lru |
+ 1 << PG_active |
+ 1 << PG_reclaim))) {
+ printk(KERN_WARNING "fuse: trying to steal weird page\n");
+ printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
+ return 1;
+ }
+ return 0;
+}
+
+static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
+{
+ int err;
+ struct page *oldpage = *pagep;
+ struct page *newpage;
+ struct pipe_buffer *buf = cs->pipebufs;
+ struct address_space *mapping;
+ pgoff_t index;
+
+ unlock_request(cs->fc, cs->req);
+ fuse_copy_finish(cs);
+
+ err = buf->ops->confirm(cs->pipe, buf);
+ if (err)
+ return err;
+
+ BUG_ON(!cs->nr_segs);
+ cs->currbuf = buf;
+ cs->len = buf->len;
+ cs->pipebufs++;
+ cs->nr_segs--;
+
+ if (cs->len != PAGE_SIZE)
+ goto out_fallback;
+
+ if (buf->ops->steal(cs->pipe, buf) != 0)
+ goto out_fallback;
+
+ newpage = buf->page;
+
+ if (WARN_ON(!PageUptodate(newpage)))
+ return -EIO;
+
+ ClearPageMappedToDisk(newpage);
+
+ if (fuse_check_page(newpage) != 0)
+ goto out_fallback_unlock;
+
+ mapping = oldpage->mapping;
+ index = oldpage->index;
+
+ /*
+ * This is a new and locked page, it shouldn't be mapped or
+ * have any special flags on it
+ */
+ if (WARN_ON(page_mapped(oldpage)))
+ goto out_fallback_unlock;
+ if (WARN_ON(page_has_private(oldpage)))
+ goto out_fallback_unlock;
+ if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
+ goto out_fallback_unlock;
+ if (WARN_ON(PageMlocked(oldpage)))
+ goto out_fallback_unlock;
+
+ remove_from_page_cache(oldpage);
+ page_cache_release(oldpage);
+
+ err = add_to_page_cache_locked(newpage, mapping, index, GFP_KERNEL);
+ if (err) {
+ printk(KERN_WARNING "fuse_try_move_page: failed to add page");
+ goto out_fallback_unlock;
+ }
+ page_cache_get(newpage);
+
+ if (!(buf->flags & PIPE_BUF_FLAG_LRU))
+ lru_cache_add_file(newpage);
+
+ err = 0;
+ spin_lock(&cs->fc->lock);
+ if (cs->req->aborted)
+ err = -ENOENT;
+ else
+ *pagep = newpage;
+ spin_unlock(&cs->fc->lock);
+
+ if (err) {
+ unlock_page(newpage);
+ page_cache_release(newpage);
+ return err;
+ }
+
+ unlock_page(oldpage);
+ page_cache_release(oldpage);
+ cs->len = 0;
+
+ return 0;
+
+out_fallback_unlock:
+ unlock_page(newpage);
+out_fallback:
+ cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
+ cs->buf = cs->mapaddr + buf->offset;
+
+ err = lock_request(cs->fc, cs->req);
+ if (err)
+ return err;
+
+ return 1;
+}
+
/*
* Copy a page in the request to/from the userspace buffer. Must be
* done atomically
*/
-static int fuse_copy_page(struct fuse_copy_state *cs, struct page *page,
+static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
unsigned offset, unsigned count, int zeroing)
{
+ int err;
+ struct page *page = *pagep;
+
if (page && zeroing && count < PAGE_SIZE) {
void *mapaddr = kmap_atomic(page, KM_USER1);
memset(mapaddr, 0, PAGE_SIZE);
@@ -623,9 +748,16 @@ static int fuse_copy_page(struct fuse_copy_state *cs, struct page *page,
}
while (count) {
if (!cs->len) {
- int err = fuse_copy_fill(cs);
- if (err)
- return err;
+ if (cs->move_pages && page &&
+ offset == 0 && count == PAGE_SIZE) {
+ err = fuse_try_move_page(cs, pagep);
+ if (err <= 0)
+ return err;
+ } else {
+ err = fuse_copy_fill(cs);
+ if (err)
+ return err;
+ }
}
if (page) {
void *mapaddr = kmap_atomic(page, KM_USER1);
@@ -650,8 +782,10 @@ static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
unsigned count = min(nbytes, (unsigned) PAGE_SIZE - offset);
for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
- struct page *page = req->pages[i];
- int err = fuse_copy_page(cs, page, offset, count, zeroing);
+ int err;
+
+ err = fuse_copy_page(cs, &req->pages[i], offset, count,
+ zeroing);
if (err)
return err;
@@ -1079,6 +1213,8 @@ static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
req->out.h = oh;
req->locked = 1;
cs->req = req;
+ if (!req->out.page_replace)
+ cs->move_pages = 0;
spin_unlock(&fc->lock);
err = copy_out_args(cs, &req->out, nbytes);
@@ -1182,6 +1318,9 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
cs.nr_segs = nbuf;
cs.pipe = pipe;
+ if (flags & SPLICE_F_MOVE)
+ cs.move_pages = 1;
+
ret = fuse_dev_do_write(fc, &cs, len);
for (idx = 0; idx < nbuf; idx++) {
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 9ca68ed..06e3775 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -517,17 +517,26 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
int i;
size_t count = req->misc.read.in.size;
size_t num_read = req->out.args[0].size;
- struct inode *inode = req->pages[0]->mapping->host;
+ struct address_space *mapping = NULL;
- /*
- * Short read means EOF. If file size is larger, truncate it
- */
- if (!req->out.h.error && num_read < count) {
- loff_t pos = page_offset(req->pages[0]) + num_read;
- fuse_read_update_size(inode, pos, req->misc.read.attr_ver);
- }
+ for (i = 0; mapping == NULL && i < req->num_pages; i++)
+ mapping = req->pages[i]->mapping;
- fuse_invalidate_attr(inode); /* atime changed */
+ if (mapping) {
+ struct inode *inode = mapping->host;
+
+ /*
+ * Short read means EOF. If file size is larger, truncate it
+ */
+ if (!req->out.h.error && num_read < count) {
+ loff_t pos;
+
+ pos = page_offset(req->pages[0]) + num_read;
+ fuse_read_update_size(inode, pos,
+ req->misc.read.attr_ver);
+ }
+ fuse_invalidate_attr(inode); /* atime changed */
+ }
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
@@ -551,6 +560,7 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file)
req->out.argpages = 1;
req->out.page_zeroing = 1;
+ req->out.page_replace = 1;
fuse_read_fill(req, file, pos, count, FUSE_READ);
req->misc.read.attr_ver = fuse_get_attr_version(fc);
if (fc->async_read) {
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 01cc462..9d0a518 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -177,6 +177,9 @@ struct fuse_out {
/** Zero partially or not copied pages */
unsigned page_zeroing:1;
+ /** Pages may be replaced with new ones */
+ unsigned page_replace:1;
+
/** Number or arguments */
unsigned numargs;
generated by cgit v1.1 at 2024-10-30 12:41:41 +0000