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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-22 23:05:34 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-22 23:05:34 +0300
commit9f15dec81339a76d91daebc53021daf56b8b15b9 (patch)
treea63ba17fa05d0dc51450987b16a73ad4d66a3dfd /fs
parent55fc733c7e1de05a03237d857f4fe6dcec52d8d9 (diff)
parent742f992708dff0ada8b426228900ffb009c7167b (diff)
downloadlinux-9f15dec81339a76d91daebc53021daf56b8b15b9.tar.xz
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse update from Miklos Szeredi: "This contains direct I/O fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: return patrial success from fuse_direct_io() fuse: Add reference counting for fuse_io_priv fuse: do not use iocb after it may have been freed
Diffstat (limited to 'fs')
-rw-r--r--fs/fuse/cuse.c4
-rw-r--r--fs/fuse/file.c56
-rw-r--r--fs/fuse/fuse_i.h9
3 files changed, 46 insertions, 23 deletions
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 8e3ee1936c7e..c5b6b7165489 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -90,7 +90,7 @@ static struct list_head *cuse_conntbl_head(dev_t devt)
static ssize_t cuse_read_iter(struct kiocb *kiocb, struct iov_iter *to)
{
- struct fuse_io_priv io = { .async = 0, .file = kiocb->ki_filp };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
loff_t pos = 0;
return fuse_direct_io(&io, to, &pos, FUSE_DIO_CUSE);
@@ -98,7 +98,7 @@ static ssize_t cuse_read_iter(struct kiocb *kiocb, struct iov_iter *to)
static ssize_t cuse_write_iter(struct kiocb *kiocb, struct iov_iter *from)
{
- struct fuse_io_priv io = { .async = 0, .file = kiocb->ki_filp };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
loff_t pos = 0;
/*
* No locking or generic_write_checks(), the server is
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index b03d253ece15..9dde38f12c07 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -528,6 +528,11 @@ static void fuse_release_user_pages(struct fuse_req *req, int write)
}
}
+static void fuse_io_release(struct kref *kref)
+{
+ kfree(container_of(kref, struct fuse_io_priv, refcnt));
+}
+
static ssize_t fuse_get_res_by_io(struct fuse_io_priv *io)
{
if (io->err)
@@ -585,8 +590,9 @@ static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
}
io->iocb->ki_complete(io->iocb, res, 0);
- kfree(io);
}
+
+ kref_put(&io->refcnt, fuse_io_release);
}
static void fuse_aio_complete_req(struct fuse_conn *fc, struct fuse_req *req)
@@ -613,6 +619,7 @@ static size_t fuse_async_req_send(struct fuse_conn *fc, struct fuse_req *req,
size_t num_bytes, struct fuse_io_priv *io)
{
spin_lock(&io->lock);
+ kref_get(&io->refcnt);
io->size += num_bytes;
io->reqs++;
spin_unlock(&io->lock);
@@ -691,7 +698,7 @@ static void fuse_short_read(struct fuse_req *req, struct inode *inode,
static int fuse_do_readpage(struct file *file, struct page *page)
{
- struct fuse_io_priv io = { .async = 0, .file = file };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
@@ -984,7 +991,7 @@ static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
size_t res;
unsigned offset;
unsigned i;
- struct fuse_io_priv io = { .async = 0, .file = file };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
for (i = 0; i < req->num_pages; i++)
fuse_wait_on_page_writeback(inode, req->pages[i]->index);
@@ -1240,6 +1247,7 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
size_t *nbytesp, int write)
{
size_t nbytes = 0; /* # bytes already packed in req */
+ ssize_t ret = 0;
/* Special case for kernel I/O: can copy directly into the buffer */
if (ii->type & ITER_KVEC) {
@@ -1259,13 +1267,12 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
unsigned npages;
size_t start;
- ssize_t ret = iov_iter_get_pages(ii,
- &req->pages[req->num_pages],
+ ret = iov_iter_get_pages(ii, &req->pages[req->num_pages],
*nbytesp - nbytes,
req->max_pages - req->num_pages,
&start);
if (ret < 0)
- return ret;
+ break;
iov_iter_advance(ii, ret);
nbytes += ret;
@@ -1288,7 +1295,7 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
*nbytesp = nbytes;
- return 0;
+ return ret;
}
static inline int fuse_iter_npages(const struct iov_iter *ii_p)
@@ -1312,6 +1319,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
pgoff_t idx_to = (pos + count - 1) >> PAGE_CACHE_SHIFT;
ssize_t res = 0;
struct fuse_req *req;
+ int err = 0;
if (io->async)
req = fuse_get_req_for_background(fc, fuse_iter_npages(iter));
@@ -1332,11 +1340,9 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
size_t nres;
fl_owner_t owner = current->files;
size_t nbytes = min(count, nmax);
- int err = fuse_get_user_pages(req, iter, &nbytes, write);
- if (err) {
- res = err;
+ err = fuse_get_user_pages(req, iter, &nbytes, write);
+ if (err && !nbytes)
break;
- }
if (write)
nres = fuse_send_write(req, io, pos, nbytes, owner);
@@ -1346,11 +1352,11 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
if (!io->async)
fuse_release_user_pages(req, !write);
if (req->out.h.error) {
- if (!res)
- res = req->out.h.error;
+ err = req->out.h.error;
break;
} else if (nres > nbytes) {
- res = -EIO;
+ res = 0;
+ err = -EIO;
break;
}
count -= nres;
@@ -1374,7 +1380,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
if (res > 0)
*ppos = pos;
- return res;
+ return res > 0 ? res : err;
}
EXPORT_SYMBOL_GPL(fuse_direct_io);
@@ -1398,7 +1404,7 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
static ssize_t fuse_direct_read_iter(struct kiocb *iocb, struct iov_iter *to)
{
- struct fuse_io_priv io = { .async = 0, .file = iocb->ki_filp };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb->ki_filp);
return __fuse_direct_read(&io, to, &iocb->ki_pos);
}
@@ -1406,7 +1412,7 @@ static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
- struct fuse_io_priv io = { .async = 0, .file = file };
+ struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
ssize_t res;
if (is_bad_inode(inode))
@@ -2843,6 +2849,7 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
loff_t i_size;
size_t count = iov_iter_count(iter);
struct fuse_io_priv *io;
+ bool is_sync = is_sync_kiocb(iocb);
pos = offset;
inode = file->f_mapping->host;
@@ -2863,6 +2870,7 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
if (!io)
return -ENOMEM;
spin_lock_init(&io->lock);
+ kref_init(&io->refcnt);
io->reqs = 1;
io->bytes = -1;
io->size = 0;
@@ -2882,12 +2890,18 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
* to wait on real async I/O requests, so we must submit this request
* synchronously.
*/
- if (!is_sync_kiocb(iocb) && (offset + count > i_size) &&
+ if (!is_sync && (offset + count > i_size) &&
iov_iter_rw(iter) == WRITE)
io->async = false;
- if (io->async && is_sync_kiocb(iocb))
+ if (io->async && is_sync) {
+ /*
+ * Additional reference to keep io around after
+ * calling fuse_aio_complete()
+ */
+ kref_get(&io->refcnt);
io->done = &wait;
+ }
if (iov_iter_rw(iter) == WRITE) {
ret = fuse_direct_io(io, iter, &pos, FUSE_DIO_WRITE);
@@ -2900,14 +2914,14 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset)
fuse_aio_complete(io, ret < 0 ? ret : 0, -1);
/* we have a non-extending, async request, so return */
- if (!is_sync_kiocb(iocb))
+ if (!is_sync)
return -EIOCBQUEUED;
wait_for_completion(&wait);
ret = fuse_get_res_by_io(io);
}
- kfree(io);
+ kref_put(&io->refcnt, fuse_io_release);
if (iov_iter_rw(iter) == WRITE) {
if (ret > 0)
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index ce394b5fe6b4..eddbe02c4028 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -22,6 +22,7 @@
#include <linux/rbtree.h>
#include <linux/poll.h>
#include <linux/workqueue.h>
+#include <linux/kref.h>
/** Max number of pages that can be used in a single read request */
#define FUSE_MAX_PAGES_PER_REQ 32
@@ -243,6 +244,7 @@ struct fuse_args {
/** The request IO state (for asynchronous processing) */
struct fuse_io_priv {
+ struct kref refcnt;
int async;
spinlock_t lock;
unsigned reqs;
@@ -256,6 +258,13 @@ struct fuse_io_priv {
struct completion *done;
};
+#define FUSE_IO_PRIV_SYNC(f) \
+{ \
+ .refcnt = { ATOMIC_INIT(1) }, \
+ .async = 0, \
+ .file = f, \
+}
+
/**
* Request flags
*