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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-30 09:16:14 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-30 09:16:14 -0700
commit003386fff3e02e51cea882e60f7d28290113964c (patch)
tree253001a9a0fc609b757362708edc2dcaab9e2a14 /fs/fuse/dev.c
parent092405cdb66f060918160ae730640b449ed7b827 (diff)
parent51921cb746f56983db5a373ca68deb2b0d3ddf01 (diff)
downloadop-kernel-dev-003386fff3e02e51cea882e60f7d28290113964c.zip
op-kernel-dev-003386fff3e02e51cea882e60f7d28290113964c.tar.gz
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: mm: export generic_pipe_buf_*() to modules fuse: support splice() reading from fuse device fuse: allow splice to move pages mm: export remove_from_page_cache() to modules mm: export lru_cache_add_*() to modules fuse: support splice() writing to fuse device fuse: get page reference for readpages fuse: use get_user_pages_fast() fuse: remove unneeded variable
Diffstat (limited to 'fs/fuse/dev.c')
-rw-r--r--fs/fuse/dev.c527
1 files changed, 461 insertions, 66 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index e53df5e..9424796 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -16,6 +16,9 @@
#include <linux/pagemap.h>
#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);
MODULE_ALIAS("devname:fuse");
@@ -499,6 +502,9 @@ struct fuse_copy_state {
int write;
struct fuse_req *req;
const struct iovec *iov;
+ struct pipe_buffer *pipebufs;
+ struct pipe_buffer *currbuf;
+ struct pipe_inode_info *pipe;
unsigned long nr_segs;
unsigned long seglen;
unsigned long addr;
@@ -506,16 +512,16 @@ 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,
- int write, struct fuse_req *req,
+ int write,
const struct iovec *iov, unsigned long nr_segs)
{
memset(cs, 0, sizeof(*cs));
cs->fc = fc;
cs->write = write;
- cs->req = req;
cs->iov = iov;
cs->nr_segs = nr_segs;
}
@@ -523,7 +529,18 @@ static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
/* Unmap and put previous page of userspace buffer */
static void fuse_copy_finish(struct fuse_copy_state *cs)
{
- if (cs->mapaddr) {
+ if (cs->currbuf) {
+ struct pipe_buffer *buf = cs->currbuf;
+
+ if (!cs->write) {
+ buf->ops->unmap(cs->pipe, buf, cs->mapaddr);
+ } else {
+ kunmap_atomic(cs->mapaddr, KM_USER0);
+ buf->len = PAGE_SIZE - cs->len;
+ }
+ cs->currbuf = NULL;
+ cs->mapaddr = NULL;
+ } else if (cs->mapaddr) {
kunmap_atomic(cs->mapaddr, KM_USER0);
if (cs->write) {
flush_dcache_page(cs->pg);
@@ -545,26 +562,61 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
unlock_request(cs->fc, cs->req);
fuse_copy_finish(cs);
- if (!cs->seglen) {
- BUG_ON(!cs->nr_segs);
- cs->seglen = cs->iov[0].iov_len;
- cs->addr = (unsigned long) cs->iov[0].iov_base;
- cs->iov++;
- cs->nr_segs--;
+ if (cs->pipebufs) {
+ struct pipe_buffer *buf = cs->pipebufs;
+
+ if (!cs->write) {
+ err = buf->ops->confirm(cs->pipe, buf);
+ if (err)
+ return err;
+
+ BUG_ON(!cs->nr_segs);
+ cs->currbuf = buf;
+ cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
+ cs->len = buf->len;
+ cs->buf = cs->mapaddr + buf->offset;
+ cs->pipebufs++;
+ cs->nr_segs--;
+ } else {
+ struct page *page;
+
+ if (cs->nr_segs == cs->pipe->buffers)
+ return -EIO;
+
+ page = alloc_page(GFP_HIGHUSER);
+ if (!page)
+ return -ENOMEM;
+
+ buf->page = page;
+ buf->offset = 0;
+ buf->len = 0;
+
+ cs->currbuf = buf;
+ cs->mapaddr = kmap_atomic(page, KM_USER0);
+ cs->buf = cs->mapaddr;
+ cs->len = PAGE_SIZE;
+ cs->pipebufs++;
+ cs->nr_segs++;
+ }
+ } else {
+ if (!cs->seglen) {
+ BUG_ON(!cs->nr_segs);
+ cs->seglen = cs->iov[0].iov_len;
+ cs->addr = (unsigned long) cs->iov[0].iov_base;
+ cs->iov++;
+ cs->nr_segs--;
+ }
+ err = get_user_pages_fast(cs->addr, 1, cs->write, &cs->pg);
+ if (err < 0)
+ return err;
+ BUG_ON(err != 1);
+ offset = cs->addr % PAGE_SIZE;
+ cs->mapaddr = kmap_atomic(cs->pg, KM_USER0);
+ cs->buf = cs->mapaddr + offset;
+ cs->len = min(PAGE_SIZE - offset, cs->seglen);
+ cs->seglen -= cs->len;
+ cs->addr += cs->len;
}
- down_read(&current->mm->mmap_sem);
- err = get_user_pages(current, current->mm, cs->addr, 1, cs->write, 0,
- &cs->pg, NULL);
- up_read(&current->mm->mmap_sem);
- if (err < 0)
- return err;
- BUG_ON(err != 1);
- offset = cs->addr % PAGE_SIZE;
- cs->mapaddr = kmap_atomic(cs->pg, KM_USER0);
- cs->buf = cs->mapaddr + offset;
- cs->len = min(PAGE_SIZE - offset, cs->seglen);
- cs->seglen -= cs->len;
- cs->addr += cs->len;
return lock_request(cs->fc, cs->req);
}
@@ -586,23 +638,178 @@ 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;
+}
+
+static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
+ unsigned offset, unsigned count)
+{
+ struct pipe_buffer *buf;
+
+ if (cs->nr_segs == cs->pipe->buffers)
+ return -EIO;
+
+ unlock_request(cs->fc, cs->req);
+ fuse_copy_finish(cs);
+
+ buf = cs->pipebufs;
+ page_cache_get(page);
+ buf->page = page;
+ buf->offset = offset;
+ buf->len = count;
+
+ cs->pipebufs++;
+ cs->nr_segs++;
+ cs->len = 0;
+
+ return 0;
+}
+
/*
* 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);
kunmap_atomic(mapaddr, KM_USER1);
}
while (count) {
- if (!cs->len) {
- int err = fuse_copy_fill(cs);
- if (err)
- return err;
+ if (cs->write && cs->pipebufs && page) {
+ return fuse_ref_page(cs, page, offset, count);
+ } else if (!cs->len) {
+ 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);
@@ -627,8 +834,10 @@ 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;
@@ -705,11 +914,10 @@ __acquires(&fc->lock)
*
* Called with fc->lock held, releases it
*/
-static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_req *req,
- const struct iovec *iov, unsigned long nr_segs)
+static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_copy_state *cs,
+ size_t nbytes, struct fuse_req *req)
__releases(&fc->lock)
{
- struct fuse_copy_state cs;
struct fuse_in_header ih;
struct fuse_interrupt_in arg;
unsigned reqsize = sizeof(ih) + sizeof(arg);
@@ -725,14 +933,13 @@ __releases(&fc->lock)
arg.unique = req->in.h.unique;
spin_unlock(&fc->lock);
- if (iov_length(iov, nr_segs) < reqsize)
+ if (nbytes < reqsize)
return -EINVAL;
- fuse_copy_init(&cs, fc, 1, NULL, iov, nr_segs);
- err = fuse_copy_one(&cs, &ih, sizeof(ih));
+ err = fuse_copy_one(cs, &ih, sizeof(ih));
if (!err)
- err = fuse_copy_one(&cs, &arg, sizeof(arg));
- fuse_copy_finish(&cs);
+ err = fuse_copy_one(cs, &arg, sizeof(arg));
+ fuse_copy_finish(cs);
return err ? err : reqsize;
}
@@ -746,18 +953,13 @@ __releases(&fc->lock)
* request_end(). Otherwise add it to the processing list, and set
* the 'sent' flag.
*/
-static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
+static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
+ struct fuse_copy_state *cs, size_t nbytes)
{
int err;
struct fuse_req *req;
struct fuse_in *in;
- struct fuse_copy_state cs;
unsigned reqsize;
- struct file *file = iocb->ki_filp;
- struct fuse_conn *fc = fuse_get_conn(file);
- if (!fc)
- return -EPERM;
restart:
spin_lock(&fc->lock);
@@ -777,7 +979,7 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
if (!list_empty(&fc->interrupts)) {
req = list_entry(fc->interrupts.next, struct fuse_req,
intr_entry);
- return fuse_read_interrupt(fc, req, iov, nr_segs);
+ return fuse_read_interrupt(fc, cs, nbytes, req);
}
req = list_entry(fc->pending.next, struct fuse_req, list);
@@ -787,7 +989,7 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
in = &req->in;
reqsize = in->h.len;
/* If request is too large, reply with an error and restart the read */
- if (iov_length(iov, nr_segs) < reqsize) {
+ if (nbytes < reqsize) {
req->out.h.error = -EIO;
/* SETXATTR is special, since it may contain too large data */
if (in->h.opcode == FUSE_SETXATTR)
@@ -796,12 +998,12 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
goto restart;
}
spin_unlock(&fc->lock);
- fuse_copy_init(&cs, fc, 1, req, iov, nr_segs);
- err = fuse_copy_one(&cs, &in->h, sizeof(in->h));
+ cs->req = req;
+ err = fuse_copy_one(cs, &in->h, sizeof(in->h));
if (!err)
- err = fuse_copy_args(&cs, in->numargs, in->argpages,
+ err = fuse_copy_args(cs, in->numargs, in->argpages,
(struct fuse_arg *) in->args, 0);
- fuse_copy_finish(&cs);
+ fuse_copy_finish(cs);
spin_lock(&fc->lock);
req->locked = 0;
if (req->aborted) {
@@ -829,6 +1031,110 @@ static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
return err;
}
+static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct fuse_copy_state cs;
+ struct file *file = iocb->ki_filp;
+ struct fuse_conn *fc = fuse_get_conn(file);
+ if (!fc)
+ return -EPERM;
+
+ fuse_copy_init(&cs, fc, 1, iov, nr_segs);
+
+ return fuse_dev_do_read(fc, file, &cs, iov_length(iov, nr_segs));
+}
+
+static int fuse_dev_pipe_buf_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ return 1;
+}
+
+static const struct pipe_buf_operations fuse_dev_pipe_buf_ops = {
+ .can_merge = 0,
+ .map = generic_pipe_buf_map,
+ .unmap = generic_pipe_buf_unmap,
+ .confirm = generic_pipe_buf_confirm,
+ .release = generic_pipe_buf_release,
+ .steal = fuse_dev_pipe_buf_steal,
+ .get = generic_pipe_buf_get,
+};
+
+static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
+ struct pipe_inode_info *pipe,
+ size_t len, unsigned int flags)
+{
+ int ret;
+ int page_nr = 0;
+ int do_wakeup = 0;
+ struct pipe_buffer *bufs;
+ struct fuse_copy_state cs;
+ struct fuse_conn *fc = fuse_get_conn(in);
+ if (!fc)
+ return -EPERM;
+
+ bufs = kmalloc(pipe->buffers * sizeof (struct pipe_buffer), GFP_KERNEL);
+ if (!bufs)
+ return -ENOMEM;
+
+ fuse_copy_init(&cs, fc, 1, NULL, 0);
+ cs.pipebufs = bufs;
+ cs.pipe = pipe;
+ ret = fuse_dev_do_read(fc, in, &cs, len);
+ if (ret < 0)
+ goto out;
+
+ ret = 0;
+ pipe_lock(pipe);
+
+ if (!pipe->readers) {
+ send_sig(SIGPIPE, current, 0);
+ if (!ret)
+ ret = -EPIPE;
+ goto out_unlock;
+ }
+
+ if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
+ ret = -EIO;
+ goto out_unlock;
+ }
+
+ while (page_nr < cs.nr_segs) {
+ int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
+ struct pipe_buffer *buf = pipe->bufs + newbuf;
+
+ buf->page = bufs[page_nr].page;
+ buf->offset = bufs[page_nr].offset;
+ buf->len = bufs[page_nr].len;
+ buf->ops = &fuse_dev_pipe_buf_ops;
+
+ pipe->nrbufs++;
+ page_nr++;
+ ret += buf->len;
+
+ if (pipe->inode)
+ do_wakeup = 1;
+ }
+
+out_unlock:
+ pipe_unlock(pipe);
+
+ if (do_wakeup) {
+ smp_mb();
+ if (waitqueue_active(&pipe->wait))
+ wake_up_interruptible(&pipe->wait);
+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
+ }
+
+out:
+ for (; page_nr < cs.nr_segs; page_nr++)
+ page_cache_release(bufs[page_nr].page);
+
+ kfree(bufs);
+ return ret;
+}
+
static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
struct fuse_copy_state *cs)
{
@@ -988,23 +1294,17 @@ static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
* it from the list and copy the rest of the buffer to the request.
* The request is finished by calling request_end()
*/
-static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
- unsigned long nr_segs, loff_t pos)
+static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
+ struct fuse_copy_state *cs, size_t nbytes)
{
int err;
- size_t nbytes = iov_length(iov, nr_segs);
struct fuse_req *req;
struct fuse_out_header oh;
- struct fuse_copy_state cs;
- struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
- if (!fc)
- return -EPERM;
- fuse_copy_init(&cs, fc, 0, NULL, iov, nr_segs);
if (nbytes < sizeof(struct fuse_out_header))
return -EINVAL;
- err = fuse_copy_one(&cs, &oh, sizeof(oh));
+ err = fuse_copy_one(cs, &oh, sizeof(oh));
if (err)
goto err_finish;
@@ -1017,7 +1317,7 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
* and error contains notification code.
*/
if (!oh.unique) {
- err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), &cs);
+ err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
return err ? err : nbytes;
}
@@ -1036,7 +1336,7 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
if (req->aborted) {
spin_unlock(&fc->lock);
- fuse_copy_finish(&cs);
+ fuse_copy_finish(cs);
spin_lock(&fc->lock);
request_end(fc, req);
return -ENOENT;
@@ -1053,7 +1353,7 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
queue_interrupt(fc, req);
spin_unlock(&fc->lock);
- fuse_copy_finish(&cs);
+ fuse_copy_finish(cs);
return nbytes;
}
@@ -1061,11 +1361,13 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
list_move(&req->list, &fc->io);
req->out.h = oh;
req->locked = 1;
- cs.req = req;
+ cs->req = req;
+ if (!req->out.page_replace)
+ cs->move_pages = 0;
spin_unlock(&fc->lock);
- err = copy_out_args(&cs, &req->out, nbytes);
- fuse_copy_finish(&cs);
+ err = copy_out_args(cs, &req->out, nbytes);
+ fuse_copy_finish(cs);
spin_lock(&fc->lock);
req->locked = 0;
@@ -1081,10 +1383,101 @@ static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
err_unlock:
spin_unlock(&fc->lock);
err_finish:
- fuse_copy_finish(&cs);
+ fuse_copy_finish(cs);
return err;
}
+static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct fuse_copy_state cs;
+ struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
+ if (!fc)
+ return -EPERM;
+
+ fuse_copy_init(&cs, fc, 0, iov, nr_segs);
+
+ return fuse_dev_do_write(fc, &cs, iov_length(iov, nr_segs));
+}
+
+static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
+ struct file *out, loff_t *ppos,
+ size_t len, unsigned int flags)
+{
+ unsigned nbuf;
+ unsigned idx;
+ struct pipe_buffer *bufs;
+ struct fuse_copy_state cs;
+ struct fuse_conn *fc;
+ size_t rem;
+ ssize_t ret;
+
+ fc = fuse_get_conn(out);
+ if (!fc)
+ return -EPERM;
+
+ bufs = kmalloc(pipe->buffers * sizeof (struct pipe_buffer), GFP_KERNEL);
+ if (!bufs)
+ return -ENOMEM;
+
+ pipe_lock(pipe);
+ nbuf = 0;
+ rem = 0;
+ for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
+ rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
+
+ ret = -EINVAL;
+ if (rem < len) {
+ pipe_unlock(pipe);
+ goto out;
+ }
+
+ rem = len;
+ while (rem) {
+ struct pipe_buffer *ibuf;
+ struct pipe_buffer *obuf;
+
+ BUG_ON(nbuf >= pipe->buffers);
+ BUG_ON(!pipe->nrbufs);
+ ibuf = &pipe->bufs[pipe->curbuf];
+ obuf = &bufs[nbuf];
+
+ if (rem >= ibuf->len) {
+ *obuf = *ibuf;
+ ibuf->ops = NULL;
+ pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
+ pipe->nrbufs--;
+ } else {
+ ibuf->ops->get(pipe, ibuf);
+ *obuf = *ibuf;
+ obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
+ obuf->len = rem;
+ ibuf->offset += obuf->len;
+ ibuf->len -= obuf->len;
+ }
+ nbuf++;
+ rem -= obuf->len;
+ }
+ pipe_unlock(pipe);
+
+ fuse_copy_init(&cs, fc, 0, NULL, nbuf);
+ cs.pipebufs = bufs;
+ 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++) {
+ struct pipe_buffer *buf = &bufs[idx];
+ buf->ops->release(pipe, buf);
+ }
+out:
+ kfree(bufs);
+ return ret;
+}
+
static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
{
unsigned mask = POLLOUT | POLLWRNORM;
@@ -1226,8 +1619,10 @@ const struct file_operations fuse_dev_operations = {
.llseek = no_llseek,
.read = do_sync_read,
.aio_read = fuse_dev_read,
+ .splice_read = fuse_dev_splice_read,
.write = do_sync_write,
.aio_write = fuse_dev_write,
+ .splice_write = fuse_dev_splice_write,
.poll = fuse_dev_poll,
.release = fuse_dev_release,
.fasync = fuse_dev_fasync,
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