fuse: pull iov_iter initializations up

... to fuse_direct_{read,write}().  ->direct_IO() path uses the
iov_iter passed by the caller instead.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index 13b691a..966ace8 100644 (file)
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -94,8 +94,10 @@ static ssize_t cuse_read(struct file *file, char __user *buf, size_t count,
        loff_t pos = 0;
        struct iovec iov = { .iov_base = buf, .iov_len = count };
        struct fuse_io_priv io = { .async = 0, .file = file };
+       struct iov_iter ii;
+       iov_iter_init(&ii, READ, &iov, 1, count);
 
-       return fuse_direct_io(&io, &iov, 1, count, &pos, FUSE_DIO_CUSE);
+       return fuse_direct_io(&io, &ii, &pos, FUSE_DIO_CUSE);
 }
 
 static ssize_t cuse_write(struct file *file, const char __user *buf,
@@ -104,12 +106,14 @@ static ssize_t cuse_write(struct file *file, const char __user *buf,
        loff_t pos = 0;
        struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = count };
        struct fuse_io_priv io = { .async = 0, .file = file };
+       struct iov_iter ii;
+       iov_iter_init(&ii, WRITE, &iov, 1, count);
 
        /*
         * No locking or generic_write_checks(), the server is
         * responsible for locking and sanity checks.
         */
-       return fuse_direct_io(&io, &iov, 1, count, &pos,
+       return fuse_direct_io(&io, &ii, &pos,
                              FUSE_DIO_WRITE | FUSE_DIO_CUSE);
 }
 

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 4a5519c..10e9fcd 100644 (file)
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1368,9 +1368,8 @@ static inline int fuse_iter_npages(const struct iov_iter *ii_p)
        return min(npages, FUSE_MAX_PAGES_PER_REQ);
 }
 
-ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
-                      unsigned long nr_segs, size_t count, loff_t *ppos,
-                      int flags)
+ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
+                      loff_t *ppos, int flags)
 {
        int write = flags & FUSE_DIO_WRITE;
        int cuse = flags & FUSE_DIO_CUSE;
@@ -1380,18 +1379,16 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
        struct fuse_conn *fc = ff->fc;
        size_t nmax = write ? fc->max_write : fc->max_read;
        loff_t pos = *ppos;
+       size_t count = iov_iter_count(iter);
        pgoff_t idx_from = pos >> PAGE_CACHE_SHIFT;
        pgoff_t idx_to = (pos + count - 1) >> PAGE_CACHE_SHIFT;
        ssize_t res = 0;
        struct fuse_req *req;
-       struct iov_iter ii;
-
-       iov_iter_init(&ii, write ? WRITE : READ, iov, nr_segs, count);
 
        if (io->async)
-               req = fuse_get_req_for_background(fc, fuse_iter_npages(&ii));
+               req = fuse_get_req_for_background(fc, fuse_iter_npages(iter));
        else
-               req = fuse_get_req(fc, fuse_iter_npages(&ii));
+               req = fuse_get_req(fc, fuse_iter_npages(iter));
        if (IS_ERR(req))
                return PTR_ERR(req);
 
@@ -1407,7 +1404,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
                size_t nres;
                fl_owner_t owner = current->files;
                size_t nbytes = min(count, nmax);
-               int err = fuse_get_user_pages(req, &ii, &nbytes, write);
+               int err = fuse_get_user_pages(req, iter, &nbytes, write);
                if (err) {
                        res = err;
                        break;
@@ -1437,9 +1434,9 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
                        fuse_put_request(fc, req);
                        if (io->async)
                                req = fuse_get_req_for_background(fc,
-                                       fuse_iter_npages(&ii));
+                                       fuse_iter_npages(iter));
                        else
-                               req = fuse_get_req(fc, fuse_iter_npages(&ii));
+                               req = fuse_get_req(fc, fuse_iter_npages(iter));
                        if (IS_ERR(req))
                                break;
                }
@@ -1454,9 +1451,8 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
 EXPORT_SYMBOL_GPL(fuse_direct_io);
 
 static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
-                                 const struct iovec *iov,
-                                 unsigned long nr_segs, loff_t *ppos,
-                                 size_t count)
+                                 struct iov_iter *iter,
+                                 loff_t *ppos)
 {
        ssize_t res;
        struct file *file = io->file;
@@ -1465,7 +1461,7 @@ static ssize_t __fuse_direct_read(struct fuse_io_priv *io,
        if (is_bad_inode(inode))
                return -EIO;
 
-       res = fuse_direct_io(io, iov, nr_segs, count, ppos, 0);
+       res = fuse_direct_io(io, iter, ppos, 0);
 
        fuse_invalidate_attr(inode);
 
@@ -1477,22 +1473,27 @@ static ssize_t fuse_direct_read(struct file *file, char __user *buf,
 {
        struct fuse_io_priv io = { .async = 0, .file = file };
        struct iovec iov = { .iov_base = buf, .iov_len = count };
-       return __fuse_direct_read(&io, &iov, 1, ppos, count);
+       struct iov_iter ii;
+       iov_iter_init(&ii, READ, &iov, 1, count);
+       return __fuse_direct_read(&io, &ii, ppos);
 }
 
 static ssize_t __fuse_direct_write(struct fuse_io_priv *io,
-                                  const struct iovec *iov,
-                                  unsigned long nr_segs, loff_t *ppos)
+                                  struct iov_iter *iter,
+                                  loff_t *ppos)
 {
        struct file *file = io->file;
        struct inode *inode = file_inode(file);
-       size_t count = iov_length(iov, nr_segs);
+       size_t count = iov_iter_count(iter);
        ssize_t res;
 
+
        res = generic_write_checks(file, ppos, &count, 0);
-       if (!res)
-               res = fuse_direct_io(io, iov, nr_segs, count, ppos,
-                                    FUSE_DIO_WRITE);
+       if (!res) {
+               if (iter->count > count)
+                       iter->count = count;
+               res = fuse_direct_io(io, iter, ppos, FUSE_DIO_WRITE);
+       }
 
        fuse_invalidate_attr(inode);
 
@@ -1506,13 +1507,15 @@ static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
        struct inode *inode = file_inode(file);
        ssize_t res;
        struct fuse_io_priv io = { .async = 0, .file = file };
+       struct iov_iter ii;
+       iov_iter_init(&ii, WRITE, &iov, 1, count);
 
        if (is_bad_inode(inode))
                return -EIO;
 
        /* Don't allow parallel writes to the same file */
        mutex_lock(&inode->i_mutex);
-       res = __fuse_direct_write(&io, &iov, 1, ppos);
+       res = __fuse_direct_write(&io, &ii, ppos);
        if (res > 0)
                fuse_write_update_size(inode, *ppos);
        mutex_unlock(&inode->i_mutex);
@@ -2914,6 +2917,8 @@ fuse_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter,
                if (offset >= i_size)
                        return 0;
                count = min_t(loff_t, count, fuse_round_up(i_size - offset));
+               if (iter->count > count)
+                       iter->count = count;
        }
 
        io = kmalloc(sizeof(struct fuse_io_priv), GFP_KERNEL);
@@ -2943,9 +2948,9 @@ fuse_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter,
                io->async = false;
 
        if (rw == WRITE)
-               ret = __fuse_direct_write(io, iter->iov, iter->nr_segs, &pos);
+               ret = __fuse_direct_write(io, iter, &pos);
        else
-               ret = __fuse_direct_read(io, iter->iov, iter->nr_segs, &pos, count);
+               ret = __fuse_direct_read(io, iter, &pos);
 
        if (io->async) {
                fuse_aio_complete(io, ret < 0 ? ret : 0, -1);

diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 7aa5c75..e8e47a6 100644 (file)
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -880,9 +880,8 @@ int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
 /** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
 #define FUSE_DIO_CUSE  (1 << 1)
 
-ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
-                      unsigned long nr_segs, size_t count, loff_t *ppos,
-                      int flags);
+ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
+                      loff_t *ppos, int flags);
 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
                   unsigned int flags);
 long fuse_ioctl_common(struct file *file, unsigned int cmd,