]> nv-tegra.nvidia Code Review - linux-2.6.git/commitdiff
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi...
authorLinus Torvalds <torvalds@linux-foundation.org>
Fri, 3 Apr 2009 22:27:58 +0000 (15:27 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 3 Apr 2009 22:27:58 +0000 (15:27 -0700)
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: allow private mappings of "direct_io" files
  fuse: allow kernel to access "direct_io" files

fs/fuse/dir.c
fs/fuse/file.c

index 06da05261e04a8a314881cee7e9e5988bc09c66a..8b8eebc5614bb1e1f6dcba5ecd0ad1966d831f07 100644 (file)
@@ -1032,6 +1032,7 @@ static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir)
                fuse_put_request(fc, req);
                return -ENOMEM;
        }
+       req->out.argpages = 1;
        req->num_pages = 1;
        req->pages[0] = page;
        fuse_read_fill(req, file, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);
index 4e340fedf768e92a1f3c60e8e2cd8621a7ecb87f..2b25133524a3d71ce5e80dac7b2f904e9f1599a9 100644 (file)
@@ -386,7 +386,6 @@ void fuse_read_fill(struct fuse_req *req, struct file *file,
        req->in.numargs = 1;
        req->in.args[0].size = sizeof(struct fuse_read_in);
        req->in.args[0].value = inarg;
-       req->out.argpages = 1;
        req->out.argvar = 1;
        req->out.numargs = 1;
        req->out.args[0].size = count;
@@ -453,6 +452,7 @@ static int fuse_readpage(struct file *file, struct page *page)
        attr_ver = fuse_get_attr_version(fc);
 
        req->out.page_zeroing = 1;
+       req->out.argpages = 1;
        req->num_pages = 1;
        req->pages[0] = page;
        num_read = fuse_send_read(req, file, inode, pos, count, NULL);
@@ -510,6 +510,8 @@ static void fuse_send_readpages(struct fuse_req *req, struct file *file,
        struct fuse_conn *fc = get_fuse_conn(inode);
        loff_t pos = page_offset(req->pages[0]);
        size_t count = req->num_pages << PAGE_CACHE_SHIFT;
+
+       req->out.argpages = 1;
        req->out.page_zeroing = 1;
        fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
        req->misc.read.attr_ver = fuse_get_attr_version(fc);
@@ -621,7 +623,6 @@ static void fuse_write_fill(struct fuse_req *req, struct file *file,
        inarg->flags = file ? file->f_flags : 0;
        req->in.h.opcode = FUSE_WRITE;
        req->in.h.nodeid = get_node_id(inode);
-       req->in.argpages = 1;
        req->in.numargs = 2;
        if (fc->minor < 9)
                req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE;
@@ -695,6 +696,7 @@ static int fuse_buffered_write(struct file *file, struct inode *inode,
        if (IS_ERR(req))
                return PTR_ERR(req);
 
+       req->in.argpages = 1;
        req->num_pages = 1;
        req->pages[0] = page;
        req->page_offset = offset;
@@ -771,6 +773,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req,
        size_t count = 0;
        int err;
 
+       req->in.argpages = 1;
        req->page_offset = offset;
 
        do {
@@ -935,21 +938,28 @@ static void fuse_release_user_pages(struct fuse_req *req, int write)
 }
 
 static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
-                              unsigned nbytes, int write)
+                              unsigned *nbytesp, int write)
 {
+       unsigned nbytes = *nbytesp;
        unsigned long user_addr = (unsigned long) buf;
        unsigned offset = user_addr & ~PAGE_MASK;
        int npages;
 
-       /* This doesn't work with nfsd */
-       if (!current->mm)
-               return -EPERM;
+       /* Special case for kernel I/O: can copy directly into the buffer */
+       if (segment_eq(get_fs(), KERNEL_DS)) {
+               if (write)
+                       req->in.args[1].value = (void *) user_addr;
+               else
+                       req->out.args[0].value = (void *) user_addr;
+
+               return 0;
+       }
 
        nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
        npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
        npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ);
        down_read(&current->mm->mmap_sem);
-       npages = get_user_pages(current, current->mm, user_addr, npages, write,
+       npages = get_user_pages(current, current->mm, user_addr, npages, !write,
                                0, req->pages, NULL);
        up_read(&current->mm->mmap_sem);
        if (npages < 0)
@@ -957,6 +967,15 @@ static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
 
        req->num_pages = npages;
        req->page_offset = offset;
+
+       if (write)
+               req->in.argpages = 1;
+       else
+               req->out.argpages = 1;
+
+       nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
+       *nbytesp = min(*nbytesp, nbytes);
+
        return 0;
 }
 
@@ -979,15 +998,13 @@ static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
 
        while (count) {
                size_t nres;
-               size_t nbytes_limit = min(count, nmax);
-               size_t nbytes;
-               int err = fuse_get_user_pages(req, buf, nbytes_limit, !write);
+               size_t nbytes = min(count, nmax);
+               int err = fuse_get_user_pages(req, buf, &nbytes, write);
                if (err) {
                        res = err;
                        break;
                }
-               nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
-               nbytes = min(nbytes_limit, nbytes);
+
                if (write)
                        nres = fuse_send_write(req, file, inode, pos, nbytes,
                                               current->files);
@@ -1163,6 +1180,7 @@ static int fuse_writepage_locked(struct page *page)
        fuse_write_fill(req, NULL, ff, inode, page_offset(page), 0, 1);
 
        copy_highpage(tmp_page, page);
+       req->in.argpages = 1;
        req->num_pages = 1;
        req->pages[0] = tmp_page;
        req->page_offset = 0;
@@ -1274,6 +1292,15 @@ static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
        return 0;
 }
 
+static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma)
+{
+       /* Can't provide the coherency needed for MAP_SHARED */
+       if (vma->vm_flags & VM_MAYSHARE)
+               return -ENODEV;
+
+       return generic_file_mmap(file, vma);
+}
+
 static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
                                  struct file_lock *fl)
 {
@@ -1908,6 +1935,7 @@ static const struct file_operations fuse_direct_io_file_operations = {
        .llseek         = fuse_file_llseek,
        .read           = fuse_direct_read,
        .write          = fuse_direct_write,
+       .mmap           = fuse_direct_mmap,
        .open           = fuse_open,
        .flush          = fuse_flush,
        .release        = fuse_release,
@@ -1917,7 +1945,7 @@ static const struct file_operations fuse_direct_io_file_operations = {
        .unlocked_ioctl = fuse_file_ioctl,
        .compat_ioctl   = fuse_file_compat_ioctl,
        .poll           = fuse_file_poll,
-       /* no mmap and splice_read */
+       /* no splice_read */
 };
 
 static const struct address_space_operations fuse_file_aops  = {