]> err.no Git - linux-2.6/blobdiff - fs/fuse/file.c
[PATCH] fuse: check directory aliasing in mkdir
[linux-2.6] / fs / fuse / file.c
index 96ea302db184be31d63b18b1c9ca614458cdfa57..2ca86141d13ab35f2fd4078ad682f4163ecf058c 100644 (file)
 #include <linux/slab.h>
 #include <linux/kernel.h>
 
-static int fuse_open(struct inode *inode, struct file *file)
+static struct file_operations fuse_direct_io_file_operations;
+
+static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
+                         struct fuse_open_out *outargp)
 {
        struct fuse_conn *fc = get_fuse_conn(inode);
-       struct fuse_req *req;
        struct fuse_open_in inarg;
+       struct fuse_req *req;
+       int err;
+
+       req = fuse_get_request(fc);
+       if (!req)
+               return -EINTR;
+
+       memset(&inarg, 0, sizeof(inarg));
+       inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
+       req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
+       req->in.h.nodeid = get_node_id(inode);
+       req->inode = inode;
+       req->in.numargs = 1;
+       req->in.args[0].size = sizeof(inarg);
+       req->in.args[0].value = &inarg;
+       req->out.numargs = 1;
+       req->out.args[0].size = sizeof(*outargp);
+       req->out.args[0].value = outargp;
+       request_send(fc, req);
+       err = req->out.h.error;
+       fuse_put_request(fc, req);
+
+       return err;
+}
+
+struct fuse_file *fuse_file_alloc(void)
+{
+       struct fuse_file *ff;
+       ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
+       if (ff) {
+               ff->release_req = fuse_request_alloc();
+               if (!ff->release_req) {
+                       kfree(ff);
+                       ff = NULL;
+               }
+       }
+       return ff;
+}
+
+void fuse_file_free(struct fuse_file *ff)
+{
+       fuse_request_free(ff->release_req);
+       kfree(ff);
+}
+
+void fuse_finish_open(struct inode *inode, struct file *file,
+                     struct fuse_file *ff, struct fuse_open_out *outarg)
+{
+       if (outarg->open_flags & FOPEN_DIRECT_IO)
+               file->f_op = &fuse_direct_io_file_operations;
+       if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
+               invalidate_inode_pages(inode->i_mapping);
+       ff->fh = outarg->fh;
+       file->private_data = ff;
+}
+
+int fuse_open_common(struct inode *inode, struct file *file, int isdir)
+{
        struct fuse_open_out outarg;
        struct fuse_file *ff;
        int err;
-       /* Restarting the syscall is not allowed if O_CREAT and O_EXCL
-          are both set, because creation will fail on the restart */
-       int excl = (file->f_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL);
+
+       /* VFS checks this, but only _after_ ->open() */
+       if (file->f_flags & O_DIRECT)
+               return -EINVAL;
 
        err = generic_file_open(inode, file);
        if (err)
@@ -31,82 +92,68 @@ static int fuse_open(struct inode *inode, struct file *file)
        /* If opening the root node, no lookup has been performed on
           it, so the attributes must be refreshed */
        if (get_node_id(inode) == FUSE_ROOT_ID) {
-               int err = fuse_do_getattr(inode);
+               err = fuse_do_getattr(inode);
                if (err)
                        return err;
        }
 
-       if (excl)
-               req = fuse_get_request_nonint(fc);
-       else
-               req = fuse_get_request(fc);
-       if (!req)
-               return excl ? -EINTR : -ERESTARTSYS;
-
-       err = -ENOMEM;
-       ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
+       ff = fuse_file_alloc();
        if (!ff)
-               goto out_put_request;
+               return -ENOMEM;
 
-       ff->release_req = fuse_request_alloc();
-       if (!ff->release_req) {
-               kfree(ff);
-               goto out_put_request;
-       }
-
-       memset(&inarg, 0, sizeof(inarg));
-       inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
-       req->in.h.opcode = FUSE_OPEN;
-       req->in.h.nodeid = get_node_id(inode);
-       req->inode = inode;
-       req->in.numargs = 1;
-       req->in.args[0].size = sizeof(inarg);
-       req->in.args[0].value = &inarg;
-       req->out.numargs = 1;
-       req->out.args[0].size = sizeof(outarg);
-       req->out.args[0].value = &outarg;
-       if (excl)
-               request_send_nonint(fc, req);
-       else
-               request_send(fc, req);
-       err = req->out.h.error;
-       if (!err && !(fc->flags & FUSE_KERNEL_CACHE))
-               invalidate_inode_pages(inode->i_mapping);
-       if (err) {
-               fuse_request_free(ff->release_req);
-               kfree(ff);
-       } else {
-               ff->fh = outarg.fh;
-               file->private_data = ff;
+       err = fuse_send_open(inode, file, isdir, &outarg);
+       if (err)
+               fuse_file_free(ff);
+       else {
+               if (isdir)
+                       outarg.open_flags &= ~FOPEN_DIRECT_IO;
+               fuse_finish_open(inode, file, ff, &outarg);
        }
 
- out_put_request:
-       fuse_put_request(fc, req);
        return err;
 }
 
-static int fuse_release(struct inode *inode, struct file *file)
+void fuse_send_release(struct fuse_conn *fc, struct fuse_file *ff,
+                      u64 nodeid, struct inode *inode, int flags, int isdir)
 {
-       struct fuse_conn *fc = get_fuse_conn(inode);
-       struct fuse_file *ff = file->private_data;
-       struct fuse_req *req = ff->release_req;
+       struct fuse_req * req = ff->release_req;
        struct fuse_release_in *inarg = &req->misc.release_in;
 
        inarg->fh = ff->fh;
-       inarg->flags = file->f_flags & ~O_EXCL;
-       req->in.h.opcode = FUSE_RELEASE;
-       req->in.h.nodeid = get_node_id(inode);
+       inarg->flags = flags;
+       req->in.h.opcode = isdir ? FUSE_RELEASEDIR : FUSE_RELEASE;
+       req->in.h.nodeid = nodeid;
        req->inode = inode;
        req->in.numargs = 1;
        req->in.args[0].size = sizeof(struct fuse_release_in);
        req->in.args[0].value = inarg;
        request_send_background(fc, req);
        kfree(ff);
+}
+
+int fuse_release_common(struct inode *inode, struct file *file, int isdir)
+{
+       struct fuse_file *ff = file->private_data;
+       if (ff) {
+               struct fuse_conn *fc = get_fuse_conn(inode);
+               u64 nodeid = get_node_id(inode);
+               fuse_send_release(fc, ff, nodeid, inode, file->f_flags, isdir);
+       }
 
        /* Return value is ignored by VFS */
        return 0;
 }
 
+static int fuse_open(struct inode *inode, struct file *file)
+{
+       return fuse_open_common(inode, file, 0);
+}
+
+static int fuse_release(struct inode *inode, struct file *file)
+{
+       return fuse_release_common(inode, file, 0);
+}
+
 static int fuse_flush(struct file *file)
 {
        struct inode *inode = file->f_dentry->d_inode;
@@ -119,7 +166,7 @@ static int fuse_flush(struct file *file)
        if (fc->no_flush)
                return 0;
 
-       req = fuse_get_request_nonint(fc);
+       req = fuse_get_request(fc);
        if (!req)
                return -EINTR;
 
@@ -132,7 +179,7 @@ static int fuse_flush(struct file *file)
        req->in.numargs = 1;
        req->in.args[0].size = sizeof(inarg);
        req->in.args[0].value = &inarg;
-       request_send_nonint(fc, req);
+       request_send(fc, req);
        err = req->out.h.error;
        fuse_put_request(fc, req);
        if (err == -ENOSYS) {
@@ -142,7 +189,8 @@ static int fuse_flush(struct file *file)
        return err;
 }
 
-static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
+int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
+                     int isdir)
 {
        struct inode *inode = de->d_inode;
        struct fuse_conn *fc = get_fuse_conn(inode);
@@ -151,17 +199,17 @@ static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
        struct fuse_fsync_in inarg;
        int err;
 
-       if (fc->no_fsync)
+       if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
                return 0;
 
        req = fuse_get_request(fc);
        if (!req)
-               return -ERESTARTSYS;
+               return -EINTR;
 
        memset(&inarg, 0, sizeof(inarg));
        inarg.fh = ff->fh;
        inarg.fsync_flags = datasync ? 1 : 0;
-       req->in.h.opcode = FUSE_FSYNC;
+       req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
        req->in.h.nodeid = get_node_id(inode);
        req->inode = inode;
        req->file = file;
@@ -172,14 +220,23 @@ static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
        err = req->out.h.error;
        fuse_put_request(fc, req);
        if (err == -ENOSYS) {
-               fc->no_fsync = 1;
+               if (isdir)
+                       fc->no_fsyncdir = 1;
+               else
+                       fc->no_fsync = 1;
                err = 0;
        }
        return err;
 }
 
-static ssize_t fuse_send_read(struct fuse_req *req, struct file *file,
-                             struct inode *inode, loff_t pos,  size_t count)
+static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
+{
+       return fuse_fsync_common(file, de, datasync, 0);
+}
+
+size_t fuse_send_read_common(struct fuse_req *req, struct file *file,
+                            struct inode *inode, loff_t pos, size_t count,
+                            int isdir)
 {
        struct fuse_conn *fc = get_fuse_conn(inode);
        struct fuse_file *ff = file->private_data;
@@ -189,7 +246,7 @@ static ssize_t fuse_send_read(struct fuse_req *req, struct file *file,
        inarg.fh = ff->fh;
        inarg.offset = pos;
        inarg.size = count;
-       req->in.h.opcode = FUSE_READ;
+       req->in.h.opcode = isdir ? FUSE_READDIR : FUSE_READ;
        req->in.h.nodeid = get_node_id(inode);
        req->inode = inode;
        req->file = file;
@@ -200,16 +257,23 @@ static ssize_t fuse_send_read(struct fuse_req *req, struct file *file,
        req->out.argvar = 1;
        req->out.numargs = 1;
        req->out.args[0].size = count;
-       request_send_nonint(fc, req);
+       request_send(fc, req);
        return req->out.args[0].size;
 }
 
+static inline size_t fuse_send_read(struct fuse_req *req, struct file *file,
+                                   struct inode *inode, loff_t pos,
+                                   size_t count)
+{
+       return fuse_send_read_common(req, file, inode, pos, count, 0);
+}
+
 static int fuse_readpage(struct file *file, struct page *page)
 {
        struct inode *inode = page->mapping->host;
        struct fuse_conn *fc = get_fuse_conn(inode);
        loff_t pos = (loff_t) page->index << PAGE_CACHE_SHIFT;
-       struct fuse_req *req = fuse_get_request_nonint(fc);
+       struct fuse_req *req = fuse_get_request(fc);
        int err = -EINTR;
        if (!req)
                goto out;
@@ -222,13 +286,81 @@ static int fuse_readpage(struct file *file, struct page *page)
        fuse_put_request(fc, req);
        if (!err)
                SetPageUptodate(page);
+       fuse_invalidate_attr(inode); /* atime changed */
  out:
        unlock_page(page);
        return err;
 }
 
-static ssize_t fuse_send_write(struct fuse_req *req, struct file *file,
-                              struct inode *inode, loff_t pos, size_t count)
+static int fuse_send_readpages(struct fuse_req *req, struct file *file,
+                              struct inode *inode)
+{
+       loff_t pos = (loff_t) req->pages[0]->index << PAGE_CACHE_SHIFT;
+       size_t count = req->num_pages << PAGE_CACHE_SHIFT;
+       unsigned i;
+       req->out.page_zeroing = 1;
+       fuse_send_read(req, file, inode, pos, count);
+       for (i = 0; i < req->num_pages; i++) {
+               struct page *page = req->pages[i];
+               if (!req->out.h.error)
+                       SetPageUptodate(page);
+               unlock_page(page);
+       }
+       return req->out.h.error;
+}
+
+struct fuse_readpages_data {
+       struct fuse_req *req;
+       struct file *file;
+       struct inode *inode;
+};
+
+static int fuse_readpages_fill(void *_data, struct page *page)
+{
+       struct fuse_readpages_data *data = _data;
+       struct fuse_req *req = data->req;
+       struct inode *inode = data->inode;
+       struct fuse_conn *fc = get_fuse_conn(inode);
+
+       if (req->num_pages &&
+           (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
+            (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
+            req->pages[req->num_pages - 1]->index + 1 != page->index)) {
+               int err = fuse_send_readpages(req, data->file, inode);
+               if (err) {
+                       unlock_page(page);
+                       return err;
+               }
+               fuse_reset_request(req);
+       }
+       req->pages[req->num_pages] = page;
+       req->num_pages ++;
+       return 0;
+}
+
+static int fuse_readpages(struct file *file, struct address_space *mapping,
+                         struct list_head *pages, unsigned nr_pages)
+{
+       struct inode *inode = mapping->host;
+       struct fuse_conn *fc = get_fuse_conn(inode);
+       struct fuse_readpages_data data;
+       int err;
+       data.file = file;
+       data.inode = inode;
+       data.req = fuse_get_request(fc);
+       if (!data.req)
+               return -EINTR;
+
+       err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
+       if (!err && data.req->num_pages)
+               err = fuse_send_readpages(data.req, file, inode);
+       fuse_put_request(fc, data.req);
+       fuse_invalidate_attr(inode); /* atime changed */
+       return err;
+}
+
+static size_t fuse_send_write(struct fuse_req *req, struct file *file,
+                             struct inode *inode, loff_t pos, size_t count)
 {
        struct fuse_conn *fc = get_fuse_conn(inode);
        struct fuse_file *ff = file->private_data;
@@ -251,7 +383,7 @@ static ssize_t fuse_send_write(struct fuse_req *req, struct file *file,
        req->out.numargs = 1;
        req->out.args[0].size = sizeof(struct fuse_write_out);
        req->out.args[0].value = &outarg;
-       request_send_nonint(fc, req);
+       request_send(fc, req);
        return outarg.size;
 }
 
@@ -266,12 +398,12 @@ static int fuse_commit_write(struct file *file, struct page *page,
                             unsigned offset, unsigned to)
 {
        int err;
-       ssize_t nres;
+       size_t nres;
        unsigned count = to - offset;
        struct inode *inode = page->mapping->host;
        struct fuse_conn *fc = get_fuse_conn(inode);
        loff_t pos = ((loff_t) page->index << PAGE_CACHE_SHIFT) + offset;
-       struct fuse_req *req = fuse_get_request_nonint(fc);
+       struct fuse_req *req = fuse_get_request(fc);
        if (!req)
                return -EINTR;
 
@@ -292,11 +424,123 @@ static int fuse_commit_write(struct file *file, struct page *page,
                        clear_page_dirty(page);
                        SetPageUptodate(page);
                }
-       } else if (err == -EINTR || err == -EIO)
-               fuse_invalidate_attr(inode);
+       }
+       fuse_invalidate_attr(inode);
        return err;
 }
 
+static void fuse_release_user_pages(struct fuse_req *req, int write)
+{
+       unsigned i;
+
+       for (i = 0; i < req->num_pages; i++) {
+               struct page *page = req->pages[i];
+               if (write)
+                       set_page_dirty_lock(page);
+               put_page(page);
+       }
+}
+
+static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
+                              unsigned nbytes, int write)
+{
+       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;
+
+       nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
+       npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
+       npages = min(npages, FUSE_MAX_PAGES_PER_REQ);
+       down_read(&current->mm->mmap_sem);
+       npages = get_user_pages(current, current->mm, user_addr, npages, write,
+                               0, req->pages, NULL);
+       up_read(&current->mm->mmap_sem);
+       if (npages < 0)
+               return npages;
+
+       req->num_pages = npages;
+       req->page_offset = offset;
+       return 0;
+}
+
+static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
+                             size_t count, loff_t *ppos, int write)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       struct fuse_conn *fc = get_fuse_conn(inode);
+       size_t nmax = write ? fc->max_write : fc->max_read;
+       loff_t pos = *ppos;
+       ssize_t res = 0;
+       struct fuse_req *req = fuse_get_request(fc);
+       if (!req)
+               return -EINTR;
+
+       while (count) {
+               size_t tmp;
+               size_t nres;
+               size_t nbytes = min(count, nmax);
+               int err = fuse_get_user_pages(req, buf, nbytes, !write);
+               if (err) {
+                       res = err;
+                       break;
+               }
+               tmp = (req->num_pages << PAGE_SHIFT) - req->page_offset;
+               nbytes = min(nbytes, tmp);
+               if (write)
+                       nres = fuse_send_write(req, file, inode, pos, nbytes);
+               else
+                       nres = fuse_send_read(req, file, inode, pos, nbytes);
+               fuse_release_user_pages(req, !write);
+               if (req->out.h.error) {
+                       if (!res)
+                               res = req->out.h.error;
+                       break;
+               } else if (nres > nbytes) {
+                       res = -EIO;
+                       break;
+               }
+               count -= nres;
+               res += nres;
+               pos += nres;
+               buf += nres;
+               if (nres != nbytes)
+                       break;
+               if (count)
+                       fuse_reset_request(req);
+       }
+       fuse_put_request(fc, req);
+       if (res > 0) {
+               if (write && pos > i_size_read(inode))
+                       i_size_write(inode, pos);
+               *ppos = pos;
+       }
+       fuse_invalidate_attr(inode);
+
+       return res;
+}
+
+static ssize_t fuse_direct_read(struct file *file, char __user *buf,
+                                    size_t count, loff_t *ppos)
+{
+       return fuse_direct_io(file, buf, count, ppos, 0);
+}
+
+static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
+                                size_t count, loff_t *ppos)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       ssize_t res;
+       /* Don't allow parallel writes to the same file */
+       down(&inode->i_sem);
+       res = fuse_direct_io(file, buf, count, ppos, 1);
+       up(&inode->i_sem);
+       return res;
+}
+
 static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
 {
        if ((vma->vm_flags & VM_SHARED)) {
@@ -327,10 +571,22 @@ static struct file_operations fuse_file_operations = {
        .sendfile       = generic_file_sendfile,
 };
 
+static struct file_operations fuse_direct_io_file_operations = {
+       .llseek         = generic_file_llseek,
+       .read           = fuse_direct_read,
+       .write          = fuse_direct_write,
+       .open           = fuse_open,
+       .flush          = fuse_flush,
+       .release        = fuse_release,
+       .fsync          = fuse_fsync,
+       /* no mmap and sendfile */
+};
+
 static struct address_space_operations fuse_file_aops  = {
        .readpage       = fuse_readpage,
        .prepare_write  = fuse_prepare_write,
        .commit_write   = fuse_commit_write,
+       .readpages      = fuse_readpages,
        .set_page_dirty = fuse_set_page_dirty,
 };