void fuse_read_fill(struct fuse_req *req, struct file *file,
struct inode *inode, loff_t pos, size_t count, int opcode)
{
- struct fuse_read_in *inarg = &req->misc.read_in;
+ struct fuse_read_in *inarg = &req->misc.read.in;
struct fuse_file *ff = file->private_data;
inarg->fh = ff->fh;
fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
if (owner != NULL) {
- struct fuse_read_in *inarg = &req->misc.read_in;
+ struct fuse_read_in *inarg = &req->misc.read.in;
inarg->read_flags |= FUSE_READ_LOCKOWNER;
inarg->lock_owner = fuse_lock_owner_id(fc, owner);
return req->out.args[0].size;
}
+static void fuse_read_update_size(struct inode *inode, loff_t size,
+ u64 attr_ver)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ spin_lock(&fc->lock);
+ if (attr_ver == fi->attr_version && size < inode->i_size) {
+ fi->attr_version = ++fc->attr_version;
+ i_size_write(inode, size);
+ }
+ spin_unlock(&fc->lock);
+}
+
static int fuse_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
+ size_t num_read;
+ loff_t pos = page_offset(page);
+ size_t count = PAGE_CACHE_SIZE;
+ u64 attr_ver;
int err;
err = -EIO;
if (IS_ERR(req))
goto out;
+ attr_ver = fuse_get_attr_version(fc);
+
req->out.page_zeroing = 1;
req->num_pages = 1;
req->pages[0] = page;
- fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE,
- NULL);
+ num_read = fuse_send_read(req, file, inode, pos, count, NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
- if (!err)
+
+ if (!err) {
+ /*
+ * Short read means EOF. If file size is larger, truncate it
+ */
+ if (num_read < count)
+ fuse_read_update_size(inode, pos + num_read, attr_ver);
+
SetPageUptodate(page);
+ }
+
fuse_invalidate_attr(inode); /* atime changed */
out:
unlock_page(page);
static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
{
int i;
+ size_t count = req->misc.read.in.size;
+ size_t num_read = req->out.args[0].size;
+ struct inode *inode = req->pages[0]->mapping->host;
- fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
+ /*
+ * Short read means EOF. If file size is larger, truncate it
+ */
+ if (!req->out.h.error && num_read < count) {
+ loff_t pos = page_offset(req->pages[0]) + num_read;
+ fuse_read_update_size(inode, pos, req->misc.read.attr_ver);
+ }
+
+ fuse_invalidate_attr(inode); /* atime changed */
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
size_t count = req->num_pages << PAGE_CACHE_SHIFT;
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);
if (fc->async_read) {
struct fuse_file *ff = file->private_data;
req->ff = fuse_file_get(ff);
return 0;
}
+static void fuse_write_update_size(struct inode *inode, loff_t pos)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ spin_lock(&fc->lock);
+ fi->attr_version = ++fc->attr_version;
+ if (pos > inode->i_size)
+ i_size_write(inode, pos);
+ spin_unlock(&fc->lock);
+}
+
static int fuse_buffered_write(struct file *file, struct inode *inode,
loff_t pos, unsigned count, struct page *page)
{
int err;
size_t nres;
struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_inode *fi = get_fuse_inode(inode);
unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
struct fuse_req *req;
err = -EIO;
if (!err) {
pos += nres;
- spin_lock(&fc->lock);
- fi->attr_version = ++fc->attr_version;
- if (pos > inode->i_size)
- i_size_write(inode, pos);
- spin_unlock(&fc->lock);
-
+ fuse_write_update_size(inode, pos);
if (count == PAGE_CACHE_SIZE)
SetPageUptodate(page);
}
return res;
}
+static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
+ struct inode *inode, loff_t pos,
+ size_t count)
+{
+ size_t res;
+ unsigned offset;
+ unsigned i;
+
+ for (i = 0; i < req->num_pages; i++)
+ fuse_wait_on_page_writeback(inode, req->pages[i]->index);
+
+ res = fuse_send_write(req, file, inode, pos, count, NULL);
+
+ offset = req->page_offset;
+ count = res;
+ for (i = 0; i < req->num_pages; i++) {
+ struct page *page = req->pages[i];
+
+ if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE)
+ SetPageUptodate(page);
+
+ if (count > PAGE_CACHE_SIZE - offset)
+ count -= PAGE_CACHE_SIZE - offset;
+ else
+ count = 0;
+ offset = 0;
+
+ unlock_page(page);
+ page_cache_release(page);
+ }
+
+ return res;
+}
+
+static ssize_t fuse_fill_write_pages(struct fuse_req *req,
+ struct address_space *mapping,
+ struct iov_iter *ii, loff_t pos)
+{
+ struct fuse_conn *fc = get_fuse_conn(mapping->host);
+ unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+ size_t count = 0;
+ int err;
+
+ req->page_offset = offset;
+
+ do {
+ size_t tmp;
+ struct page *page;
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset,
+ iov_iter_count(ii));
+
+ bytes = min_t(size_t, bytes, fc->max_write - count);
+
+ again:
+ err = -EFAULT;
+ if (iov_iter_fault_in_readable(ii, bytes))
+ break;
+
+ err = -ENOMEM;
+ page = __grab_cache_page(mapping, index);
+ if (!page)
+ break;
+
+ pagefault_disable();
+ tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes);
+ pagefault_enable();
+ flush_dcache_page(page);
+
+ if (!tmp) {
+ unlock_page(page);
+ page_cache_release(page);
+ bytes = min(bytes, iov_iter_single_seg_count(ii));
+ goto again;
+ }
+
+ err = 0;
+ req->pages[req->num_pages] = page;
+ req->num_pages++;
+
+ iov_iter_advance(ii, tmp);
+ count += tmp;
+ pos += tmp;
+ offset += tmp;
+ if (offset == PAGE_CACHE_SIZE)
+ offset = 0;
+
+ if (!fc->big_writes)
+ break;
+ } while (iov_iter_count(ii) && count < fc->max_write &&
+ req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0);
+
+ return count > 0 ? count : err;
+}
+
+static ssize_t fuse_perform_write(struct file *file,
+ struct address_space *mapping,
+ struct iov_iter *ii, loff_t pos)
+{
+ struct inode *inode = mapping->host;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ int err = 0;
+ ssize_t res = 0;
+
+ if (is_bad_inode(inode))
+ return -EIO;
+
+ do {
+ struct fuse_req *req;
+ ssize_t count;
+
+ req = fuse_get_req(fc);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ break;
+ }
+
+ count = fuse_fill_write_pages(req, mapping, ii, pos);
+ if (count <= 0) {
+ err = count;
+ } else {
+ size_t num_written;
+
+ num_written = fuse_send_write_pages(req, file, inode,
+ pos, count);
+ err = req->out.h.error;
+ if (!err) {
+ res += num_written;
+ pos += num_written;
+
+ /* break out of the loop on short write */
+ if (num_written != count)
+ err = -EIO;
+ }
+ }
+ fuse_put_request(fc, req);
+ } while (!err && iov_iter_count(ii));
+
+ if (res > 0)
+ fuse_write_update_size(inode, pos);
+
+ fuse_invalidate_attr(inode);
+
+ return res > 0 ? res : err;
+}
+
+static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct file *file = iocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ size_t count = 0;
+ ssize_t written = 0;
+ struct inode *inode = mapping->host;
+ ssize_t err;
+ struct iov_iter i;
+
+ WARN_ON(iocb->ki_pos != pos);
+
+ err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
+ if (err)
+ return err;
+
+ mutex_lock(&inode->i_mutex);
+ vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
+
+ /* We can write back this queue in page reclaim */
+ current->backing_dev_info = mapping->backing_dev_info;
+
+ err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
+ if (err)
+ goto out;
+
+ if (count == 0)
+ goto out;
+
+ err = remove_suid(file->f_path.dentry);
+ if (err)
+ goto out;
+
+ file_update_time(file);
+
+ iov_iter_init(&i, iov, nr_segs, count, 0);
+ written = fuse_perform_write(file, mapping, &i, pos);
+ if (written >= 0)
+ iocb->ki_pos = pos + written;
+
+out:
+ current->backing_dev_info = NULL;
+ mutex_unlock(&inode->i_mutex);
+
+ return written ? written : err;
+}
+
static void fuse_release_user_pages(struct fuse_req *req, int write)
{
unsigned i;
nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
- npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
+ npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ);
down_read(¤t->mm->mmap_sem);
npages = get_user_pages(current, current->mm, user_addr, npages, write,
0, req->pages, NULL);
while (count) {
size_t nres;
- size_t nbytes = min(count, nmax);
- int err = fuse_get_user_pages(req, buf, nbytes, !write);
+ size_t nbytes_limit = min(count, nmax);
+ size_t nbytes;
+ int err = fuse_get_user_pages(req, buf, nbytes_limit, !write);
if (err) {
res = err;
break;
}
nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
- nbytes = min(count, nbytes);
+ nbytes = min(nbytes_limit, nbytes);
if (write)
nres = fuse_send_write(req, file, inode, pos, nbytes,
current->files);
}
fuse_put_request(fc, req);
if (res > 0) {
- if (write) {
- spin_lock(&fc->lock);
- if (pos > inode->i_size)
- i_size_write(inode, pos);
- spin_unlock(&fc->lock);
- }
+ if (write)
+ fuse_write_update_size(inode, pos);
*ppos = pos;
}
fuse_invalidate_attr(inode);
return err ? 0 : outarg.block;
}
+static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t retval;
+ struct inode *inode = file->f_path.dentry->d_inode;
+
+ mutex_lock(&inode->i_mutex);
+ switch (origin) {
+ case SEEK_END:
+ offset += i_size_read(inode);
+ break;
+ case SEEK_CUR:
+ offset += file->f_pos;
+ }
+ retval = -EINVAL;
+ if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ file->f_version = 0;
+ }
+ retval = offset;
+ }
+ mutex_unlock(&inode->i_mutex);
+ return retval;
+}
+
static const struct file_operations fuse_file_operations = {
- .llseek = generic_file_llseek,
+ .llseek = fuse_file_llseek,
.read = do_sync_read,
.aio_read = fuse_file_aio_read,
.write = do_sync_write,
- .aio_write = generic_file_aio_write,
+ .aio_write = fuse_file_aio_write,
.mmap = fuse_file_mmap,
.open = fuse_open,
.flush = fuse_flush,
};
static const struct file_operations fuse_direct_io_file_operations = {
- .llseek = generic_file_llseek,
+ .llseek = fuse_file_llseek,
.read = fuse_direct_read,
.write = fuse_direct_write,
.open = fuse_open,