fuse: convert ioctl to simple api

fuse_simple_request() is converted to return length of last (instead of
single) out arg, since FUSE_IOCTL_OUT has two out args, the second of which
is variable length.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 0a6624a..29723e1 100644 (file)
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -590,8 +590,8 @@ ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args)
        __fuse_request_send(fc, req);
        ret = req->out.h.error;
        if (!ret && args->out_argvar) {
-               BUG_ON(args->out_numargs != 1);
-               ret = req->out.args[0].size;
+               BUG_ON(args->out_numargs == 0);
+               ret = req->out.args[args->out_numargs - 1].size;
        }
        fuse_put_request(fc, req);
 

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index c3e9500..1847cc5 100644 (file)
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1267,14 +1267,14 @@ out:
        return written ? written : err;
 }
 
-static inline void fuse_page_descs_length_init(struct fuse_req *req,
-               unsigned index, unsigned nr_pages)
+static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
+                                              unsigned int index,
+                                              unsigned int nr_pages)
 {
        int i;
 
        for (i = index; i < index + nr_pages; i++)
-               req->page_descs[i].length = PAGE_SIZE -
-                       req->page_descs[i].offset;
+               descs[i].length = PAGE_SIZE - descs[i].offset;
 }
 
 static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
@@ -1326,7 +1326,8 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
                npages = (ret + PAGE_SIZE - 1) / PAGE_SIZE;
 
                req->page_descs[req->num_pages].offset = start;
-               fuse_page_descs_length_init(req, req->num_pages, npages);
+               fuse_page_descs_length_init(req->page_descs, req->num_pages,
+                                           npages);
 
                req->num_pages += npages;
                req->page_descs[req->num_pages - 1].length -=
@@ -2582,14 +2583,14 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
                .flags = flags
        };
        struct fuse_ioctl_out outarg;
-       struct fuse_req *req = NULL;
-       struct page **pages = NULL;
        struct iovec *iov_page = NULL;
        struct iovec *in_iov = NULL, *out_iov = NULL;
-       unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
-       size_t in_size, out_size, transferred, c;
+       unsigned int in_iovs = 0, out_iovs = 0, max_pages;
+       size_t in_size, out_size, c;
+       ssize_t transferred;
        int err, i;
        struct iov_iter ii;
+       struct fuse_args_pages ap = {};
 
 #if BITS_PER_LONG == 32
        inarg.flags |= FUSE_IOCTL_32BIT;
@@ -2607,11 +2608,13 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
        BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
 
        err = -ENOMEM;
-       pages = kcalloc(fc->max_pages, sizeof(pages[0]), GFP_KERNEL);
+       ap.pages = fuse_pages_alloc(fc->max_pages, GFP_KERNEL, &ap.descs);
        iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
-       if (!pages || !iov_page)
+       if (!ap.pages || !iov_page)
                goto out;
 
+       fuse_page_descs_length_init(ap.descs, 0, fc->max_pages);
+
        /*
         * If restricted, initialize IO parameters as encoded in @cmd.
         * RETRY from server is not allowed.
@@ -2648,56 +2651,44 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
        err = -ENOMEM;
        if (max_pages > fc->max_pages)
                goto out;
-       while (num_pages < max_pages) {
-               pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
-               if (!pages[num_pages])
+       while (ap.num_pages < max_pages) {
+               ap.pages[ap.num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+               if (!ap.pages[ap.num_pages])
                        goto out;
-               num_pages++;
+               ap.num_pages++;
        }
 
-       req = fuse_get_req(fc, num_pages);
-       if (IS_ERR(req)) {
-               err = PTR_ERR(req);
-               req = NULL;
-               goto out;
-       }
-       memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages);
-       req->num_pages = num_pages;
-       fuse_page_descs_length_init(req, 0, req->num_pages);
 
        /* okay, let's send it to the client */
-       req->in.h.opcode = FUSE_IOCTL;
-       req->in.h.nodeid = ff->nodeid;
-       req->in.numargs = 1;
-       req->in.args[0].size = sizeof(inarg);
-       req->in.args[0].value = &inarg;
+       ap.args.opcode = FUSE_IOCTL;
+       ap.args.nodeid = ff->nodeid;
+       ap.args.in_numargs = 1;
+       ap.args.in_args[0].size = sizeof(inarg);
+       ap.args.in_args[0].value = &inarg;
        if (in_size) {
-               req->in.numargs++;
-               req->in.args[1].size = in_size;
-               req->in.argpages = 1;
+               ap.args.in_numargs++;
+               ap.args.in_args[1].size = in_size;
+               ap.args.in_pages = true;
 
                err = -EFAULT;
                iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
-               for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) {
-                       c = copy_page_from_iter(pages[i], 0, PAGE_SIZE, &ii);
+               for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
+                       c = copy_page_from_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
                        if (c != PAGE_SIZE && iov_iter_count(&ii))
                                goto out;
                }
        }
 
-       req->out.numargs = 2;
-       req->out.args[0].size = sizeof(outarg);
-       req->out.args[0].value = &outarg;
-       req->out.args[1].size = out_size;
-       req->out.argpages = 1;
-       req->out.argvar = 1;
+       ap.args.out_numargs = 2;
+       ap.args.out_args[0].size = sizeof(outarg);
+       ap.args.out_args[0].value = &outarg;
+       ap.args.out_args[1].size = out_size;
+       ap.args.out_pages = true;
+       ap.args.out_argvar = true;
 
-       fuse_request_send(fc, req);
-       err = req->out.h.error;
-       transferred = req->out.args[1].size;
-       fuse_put_request(fc, req);
-       req = NULL;
-       if (err)
+       transferred = fuse_simple_request(fc, &ap.args);
+       err = transferred;
+       if (transferred < 0)
                goto out;
 
        /* did it ask for retry? */
@@ -2722,7 +2713,7 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
                    in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
                        goto out;
 
-               vaddr = kmap_atomic(pages[0]);
+               vaddr = kmap_atomic(ap.pages[0]);
                err = fuse_copy_ioctl_iovec(fc, iov_page, vaddr,
                                            transferred, in_iovs + out_iovs,
                                            (flags & FUSE_IOCTL_COMPAT) != 0);
@@ -2750,19 +2741,17 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 
        err = -EFAULT;
        iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
-       for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= num_pages); i++) {
-               c = copy_page_to_iter(pages[i], 0, PAGE_SIZE, &ii);
+       for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
+               c = copy_page_to_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
                if (c != PAGE_SIZE && iov_iter_count(&ii))
                        goto out;
        }
        err = 0;
  out:
-       if (req)
-               fuse_put_request(fc, req);
        free_page((unsigned long) iov_page);
-       while (num_pages)
-               __free_page(pages[--num_pages]);
-       kfree(pages);
+       while (ap.num_pages)
+               __free_page(ap.pages[--ap.num_pages]);
+       kfree(ap.pages);
 
        return err ? err : outarg.result;
 }