/*
FUSE: Filesystem in Userspace
- Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
+ Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/module.h>
static const 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)
+static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
+ int opcode, struct fuse_open_out *outargp)
{
- struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_open_in inarg;
struct fuse_req *req;
int err;
return PTR_ERR(req);
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);
+ inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
+ if (!fc->atomic_o_trunc)
+ inarg.flags &= ~O_TRUNC;
+ req->in.h.opcode = opcode;
+ req->in.h.nodeid = nodeid;
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);
+ fuse_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 *fuse_file_alloc(struct fuse_conn *fc)
{
struct fuse_file *ff;
+
ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
- if (ff) {
- ff->reserved_req = fuse_request_alloc();
- if (!ff->reserved_req) {
- kfree(ff);
- ff = NULL;
- }
+ if (unlikely(!ff))
+ return NULL;
+
+ ff->fc = fc;
+ ff->reserved_req = fuse_request_alloc();
+ if (unlikely(!ff->reserved_req)) {
+ kfree(ff);
+ return NULL;
}
+
+ INIT_LIST_HEAD(&ff->write_entry);
+ atomic_set(&ff->count, 0);
+ RB_CLEAR_NODE(&ff->polled_node);
+ init_waitqueue_head(&ff->poll_wait);
+
+ spin_lock(&fc->lock);
+ ff->kh = ++fc->khctr;
+ spin_unlock(&fc->lock);
+
return ff;
}
kfree(ff);
}
-void fuse_finish_open(struct inode *inode, struct file *file,
- struct fuse_file *ff, struct fuse_open_out *outarg)
+struct fuse_file *fuse_file_get(struct fuse_file *ff)
{
- 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;
+ atomic_inc(&ff->count);
+ return ff;
+}
+
+static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
+{
+ path_put(&req->misc.release.path);
+}
+
+static void fuse_file_put(struct fuse_file *ff)
+{
+ if (atomic_dec_and_test(&ff->count)) {
+ struct fuse_req *req = ff->reserved_req;
+
+ req->end = fuse_release_end;
+ fuse_request_send_background(ff->fc, req);
+ kfree(ff);
+ }
}
-int fuse_open_common(struct inode *inode, struct file *file, int isdir)
+int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
+ bool isdir)
{
struct fuse_open_out outarg;
struct fuse_file *ff;
int err;
+ int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
+
+ ff = fuse_file_alloc(fc);
+ if (!ff)
+ return -ENOMEM;
+
+ err = fuse_send_open(fc, nodeid, file, opcode, &outarg);
+ if (err) {
+ fuse_file_free(ff);
+ return err;
+ }
+
+ if (isdir)
+ outarg.open_flags &= ~FOPEN_DIRECT_IO;
+
+ ff->fh = outarg.fh;
+ ff->nodeid = nodeid;
+ ff->open_flags = outarg.open_flags;
+ file->private_data = fuse_file_get(ff);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fuse_do_open);
+
+void fuse_finish_open(struct inode *inode, struct file *file)
+{
+ struct fuse_file *ff = file->private_data;
+
+ if (ff->open_flags & FOPEN_DIRECT_IO)
+ file->f_op = &fuse_direct_io_file_operations;
+ if (!(ff->open_flags & FOPEN_KEEP_CACHE))
+ invalidate_inode_pages2(inode->i_mapping);
+ if (ff->open_flags & FOPEN_NONSEEKABLE)
+ nonseekable_open(inode, file);
+}
+
+int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ int err;
/* VFS checks this, but only _after_ ->open() */
if (file->f_flags & O_DIRECT)
if (err)
return err;
- /* 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) {
- err = fuse_do_getattr(inode);
- if (err)
- return err;
- }
-
- ff = fuse_file_alloc();
- if (!ff)
- return -ENOMEM;
-
- err = fuse_send_open(inode, file, isdir, &outarg);
+ err = fuse_do_open(fc, get_node_id(inode), file, isdir);
if (err)
- fuse_file_free(ff);
- else {
- if (isdir)
- outarg.open_flags &= ~FOPEN_DIRECT_IO;
- fuse_finish_open(inode, file, ff, &outarg);
- }
+ return err;
- return err;
+ fuse_finish_open(inode, file);
+
+ return 0;
}
-struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
- int opcode)
+static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode)
{
+ struct fuse_conn *fc = ff->fc;
struct fuse_req *req = ff->reserved_req;
- struct fuse_release_in *inarg = &req->misc.release_in;
+ struct fuse_release_in *inarg = &req->misc.release.in;
+
+ spin_lock(&fc->lock);
+ list_del(&ff->write_entry);
+ if (!RB_EMPTY_NODE(&ff->polled_node))
+ rb_erase(&ff->polled_node, &fc->polled_files);
+ spin_unlock(&fc->lock);
+
+ wake_up_interruptible_sync(&ff->poll_wait);
inarg->fh = ff->fh;
inarg->flags = flags;
req->in.h.opcode = opcode;
- req->in.h.nodeid = nodeid;
+ req->in.h.nodeid = ff->nodeid;
req->in.numargs = 1;
req->in.args[0].size = sizeof(struct fuse_release_in);
req->in.args[0].value = inarg;
- kfree(ff);
-
- return req;
}
-int fuse_release_common(struct inode *inode, struct file *file, int isdir)
+void fuse_release_common(struct file *file, int opcode)
{
- struct fuse_file *ff = file->private_data;
- if (ff) {
- struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_req *req;
+ struct fuse_file *ff;
+ struct fuse_req *req;
- req = fuse_release_fill(ff, get_node_id(inode), file->f_flags,
- isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
+ ff = file->private_data;
+ if (unlikely(!ff))
+ return;
- /* Hold vfsmount and dentry until release is finished */
- req->vfsmount = mntget(file->f_vfsmnt);
- req->dentry = dget(file->f_dentry);
- request_send_background(fc, req);
- }
+ req = ff->reserved_req;
+ fuse_prepare_release(ff, file->f_flags, opcode);
- /* Return value is ignored by VFS */
- return 0;
+ /* Hold vfsmount and dentry until release is finished */
+ path_get(&file->f_path);
+ req->misc.release.path = file->f_path;
+
+ /*
+ * Normally this will send the RELEASE request, however if
+ * some asynchronous READ or WRITE requests are outstanding,
+ * the sending will be delayed.
+ */
+ fuse_file_put(ff);
}
static int fuse_open(struct inode *inode, struct file *file)
{
- return fuse_open_common(inode, file, 0);
+ return fuse_open_common(inode, file, false);
}
static int fuse_release(struct inode *inode, struct file *file)
{
- return fuse_release_common(inode, file, 0);
+ fuse_release_common(file, FUSE_RELEASE);
+
+ /* return value is ignored by VFS */
+ return 0;
+}
+
+void fuse_sync_release(struct fuse_file *ff, int flags)
+{
+ WARN_ON(atomic_read(&ff->count) > 1);
+ fuse_prepare_release(ff, flags, FUSE_RELEASE);
+ ff->reserved_req->force = 1;
+ fuse_request_send(ff->fc, ff->reserved_req);
+ fuse_put_request(ff->fc, ff->reserved_req);
+ kfree(ff);
+}
+EXPORT_SYMBOL_GPL(fuse_sync_release);
+
+/*
+ * Scramble the ID space with XTEA, so that the value of the files_struct
+ * pointer is not exposed to userspace.
+ */
+u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
+{
+ u32 *k = fc->scramble_key;
+ u64 v = (unsigned long) id;
+ u32 v0 = v;
+ u32 v1 = v >> 32;
+ u32 sum = 0;
+ int i;
+
+ for (i = 0; i < 32; i++) {
+ v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
+ sum += 0x9E3779B9;
+ v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
+ }
+
+ return (u64) v0 + ((u64) v1 << 32);
+}
+
+/*
+ * Check if page is under writeback
+ *
+ * This is currently done by walking the list of writepage requests
+ * for the inode, which can be pretty inefficient.
+ */
+static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_req *req;
+ bool found = false;
+
+ spin_lock(&fc->lock);
+ list_for_each_entry(req, &fi->writepages, writepages_entry) {
+ pgoff_t curr_index;
+
+ BUG_ON(req->inode != inode);
+ curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
+ if (curr_index == index) {
+ found = true;
+ break;
+ }
+ }
+ spin_unlock(&fc->lock);
+
+ return found;
}
/*
- * It would be nice to scramble the ID space, so that the value of the
- * files_struct pointer is not exposed to userspace. Symmetric crypto
- * functions are overkill, since the inverse function doesn't need to
- * be implemented (though it does have to exist). Is there something
- * simpler?
+ * Wait for page writeback to be completed.
+ *
+ * Since fuse doesn't rely on the VM writeback tracking, this has to
+ * use some other means.
*/
-static inline u64 fuse_lock_owner_id(fl_owner_t id)
+static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index)
{
- return (unsigned long) id;
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index));
+ return 0;
}
static int fuse_flush(struct file *file, fl_owner_t id)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
struct fuse_req *req;
req = fuse_get_req_nofail(fc, file);
memset(&inarg, 0, sizeof(inarg));
inarg.fh = ff->fh;
- inarg.lock_owner = fuse_lock_owner_id(id);
+ inarg.lock_owner = fuse_lock_owner_id(fc, id);
req->in.h.opcode = FUSE_FLUSH;
req->in.h.nodeid = get_node_id(inode);
req->in.numargs = 1;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
req->force = 1;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {
return err;
}
-int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
- int isdir)
+/*
+ * Wait for all pending writepages on the inode to finish.
+ *
+ * This is currently done by blocking further writes with FUSE_NOWRITE
+ * and waiting for all sent writes to complete.
+ *
+ * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage
+ * could conflict with truncation.
+ */
+static void fuse_sync_writes(struct inode *inode)
+{
+ fuse_set_nowrite(inode);
+ fuse_release_nowrite(inode);
+}
+
+int fuse_fsync_common(struct file *file, int datasync, int isdir)
{
- struct inode *inode = de->d_inode;
+ struct inode *inode = file->f_mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
struct fuse_req *req;
if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
return 0;
+ /*
+ * Start writeback against all dirty pages of the inode, then
+ * wait for all outstanding writes, before sending the FSYNC
+ * request.
+ */
+ err = write_inode_now(inode, 0);
+ if (err)
+ return err;
+
+ fuse_sync_writes(inode);
+
req = fuse_get_req(fc);
if (IS_ERR(req))
return PTR_ERR(req);
req->in.numargs = 1;
req->in.args[0].size = sizeof(inarg);
req->in.args[0].value = &inarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (err == -ENOSYS) {
return err;
}
-static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
+static int fuse_fsync(struct file *file, int datasync)
{
- return fuse_fsync_common(file, de, datasync, 0);
+ return fuse_fsync_common(file, datasync, 0);
}
-void fuse_read_fill(struct fuse_req *req, struct file *file,
- struct inode *inode, loff_t pos, size_t count, int opcode)
+void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos,
+ size_t count, int opcode)
{
+ struct fuse_read_in *inarg = &req->misc.read.in;
struct fuse_file *ff = file->private_data;
- struct fuse_read_in *inarg = &req->misc.read_in;
inarg->fh = ff->fh;
inarg->offset = pos;
inarg->size = count;
+ inarg->flags = file->f_flags;
req->in.h.opcode = opcode;
- req->in.h.nodeid = get_node_id(inode);
+ req->in.h.nodeid = ff->nodeid;
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;
}
static size_t fuse_send_read(struct fuse_req *req, struct file *file,
- struct inode *inode, loff_t pos, size_t count)
+ loff_t pos, size_t count, fl_owner_t owner)
{
- struct fuse_conn *fc = get_fuse_conn(inode);
- fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
- request_send(fc, req);
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
+
+ fuse_read_fill(req, file, pos, count, FUSE_READ);
+ if (owner != NULL) {
+ struct fuse_read_in *inarg = &req->misc.read.in;
+
+ inarg->read_flags |= FUSE_READ_LOCKOWNER;
+ inarg->lock_owner = fuse_lock_owner_id(fc, owner);
+ }
+ fuse_request_send(fc, req);
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_bad_inode(inode))
goto out;
+ /*
+ * Page writeback can extend beyond the liftime of the
+ * page-cache page, so make sure we read a properly synced
+ * page.
+ */
+ fuse_wait_on_page_writeback(inode, page->index);
+
req = fuse_get_req(fc);
err = PTR_ERR(req);
if (IS_ERR(req))
goto out;
+ attr_ver = fuse_get_attr_version(fc);
+
req->out.page_zeroing = 1;
+ req->out.argpages = 1;
req->num_pages = 1;
req->pages[0] = page;
- fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
+ num_read = fuse_send_read(req, file, 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;
+
+ /*
+ * 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(req->pages[0]->mapping->host); /* atime changed */
+ fuse_invalidate_attr(inode); /* atime changed */
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
SetPageError(page);
unlock_page(page);
}
- fuse_put_request(fc, req);
+ if (req->ff)
+ fuse_file_put(req->ff);
}
-static void fuse_send_readpages(struct fuse_req *req, struct file *file,
- struct inode *inode)
+static void fuse_send_readpages(struct fuse_req *req, struct file *file)
{
- struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
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);
+ fuse_read_fill(req, file, pos, count, FUSE_READ);
+ req->misc.read.attr_ver = fuse_get_attr_version(fc);
if (fc->async_read) {
- get_file(file);
- req->file = file;
+ req->ff = fuse_file_get(ff);
req->end = fuse_readpages_end;
- request_send_background(fc, req);
+ fuse_request_send_background(fc, req);
} else {
- request_send(fc, req);
+ fuse_request_send(fc, req);
fuse_readpages_end(fc, req);
+ fuse_put_request(fc, req);
}
}
-struct fuse_readpages_data {
+struct fuse_fill_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_fill_data *data = _data;
struct fuse_req *req = data->req;
struct inode *inode = data->inode;
struct fuse_conn *fc = get_fuse_conn(inode);
+ fuse_wait_on_page_writeback(inode, page->index);
+
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)) {
- fuse_send_readpages(req, data->file, inode);
+ fuse_send_readpages(req, data->file);
data->req = req = fuse_get_req(fc);
if (IS_ERR(req)) {
unlock_page(page);
}
}
req->pages[req->num_pages] = page;
- req->num_pages ++;
+ req->num_pages++;
return 0;
}
{
struct inode *inode = mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_readpages_data data;
+ struct fuse_fill_data data;
int err;
+ err = -EIO;
if (is_bad_inode(inode))
- return -EIO;
+ goto out;
data.file = file;
data.inode = inode;
data.req = fuse_get_req(fc);
+ err = PTR_ERR(data.req);
if (IS_ERR(data.req))
- return PTR_ERR(data.req);
+ goto out;
err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
if (!err) {
if (data.req->num_pages)
- fuse_send_readpages(data.req, file, inode);
+ fuse_send_readpages(data.req, file);
else
fuse_put_request(fc, data.req);
}
+out:
return err;
}
-static size_t fuse_send_write(struct fuse_req *req, struct file *file,
- struct inode *inode, loff_t pos, size_t count)
+static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
{
- struct fuse_conn *fc = get_fuse_conn(inode);
- struct fuse_file *ff = file->private_data;
- struct fuse_write_in inarg;
- struct fuse_write_out outarg;
+ struct inode *inode = iocb->ki_filp->f_mapping->host;
+
+ if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) {
+ int err;
+ /*
+ * If trying to read past EOF, make sure the i_size
+ * attribute is up-to-date.
+ */
+ err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL);
+ if (err)
+ return err;
+ }
- memset(&inarg, 0, sizeof(struct fuse_write_in));
- inarg.fh = ff->fh;
- inarg.offset = pos;
- inarg.size = count;
+ return generic_file_aio_read(iocb, iov, nr_segs, pos);
+}
+
+static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff,
+ loff_t pos, size_t count)
+{
+ struct fuse_write_in *inarg = &req->misc.write.in;
+ struct fuse_write_out *outarg = &req->misc.write.out;
+
+ inarg->fh = ff->fh;
+ inarg->offset = pos;
+ inarg->size = count;
req->in.h.opcode = FUSE_WRITE;
- req->in.h.nodeid = get_node_id(inode);
- req->in.argpages = 1;
+ req->in.h.nodeid = ff->nodeid;
req->in.numargs = 2;
- req->in.args[0].size = sizeof(struct fuse_write_in);
- req->in.args[0].value = &inarg;
+ if (ff->fc->minor < 9)
+ req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE;
+ else
+ req->in.args[0].size = sizeof(struct fuse_write_in);
+ req->in.args[0].value = inarg;
req->in.args[1].size = count;
req->out.numargs = 1;
req->out.args[0].size = sizeof(struct fuse_write_out);
- req->out.args[0].value = &outarg;
- request_send(fc, req);
- return outarg.size;
+ req->out.args[0].value = outarg;
+}
+
+static size_t fuse_send_write(struct fuse_req *req, struct file *file,
+ loff_t pos, size_t count, fl_owner_t owner)
+{
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
+ struct fuse_write_in *inarg = &req->misc.write.in;
+
+ fuse_write_fill(req, ff, pos, count);
+ inarg->flags = file->f_flags;
+ if (owner != NULL) {
+ inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
+ inarg->lock_owner = fuse_lock_owner_id(fc, owner);
+ }
+ fuse_request_send(fc, req);
+ return req->misc.write.out.size;
}
-static int fuse_prepare_write(struct file *file, struct page *page,
- unsigned offset, unsigned to)
+static int fuse_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
{
- /* No op */
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+
+ *pagep = grab_cache_page_write_begin(mapping, index, flags);
+ if (!*pagep)
+ return -ENOMEM;
return 0;
}
-static int fuse_commit_write(struct file *file, struct page *page,
- unsigned offset, unsigned to)
+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;
- unsigned count = to - offset;
- struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
- loff_t pos = page_offset(page) + offset;
+ unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
struct fuse_req *req;
if (is_bad_inode(inode))
return -EIO;
+ /*
+ * Make sure writepages on the same page are not mixed up with
+ * plain writes.
+ */
+ fuse_wait_on_page_writeback(inode, page->index);
+
req = fuse_get_req(fc);
if (IS_ERR(req))
return PTR_ERR(req);
+ req->in.argpages = 1;
req->num_pages = 1;
req->pages[0] = page;
req->page_offset = offset;
- nres = fuse_send_write(req, file, inode, pos, count);
+ nres = fuse_send_write(req, file, pos, count, NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
- if (!err && nres != count)
+ if (!err && !nres)
err = -EIO;
if (!err) {
- pos += count;
- if (pos > i_size_read(inode))
- i_size_write(inode, pos);
-
- if (offset == 0 && to == PAGE_CACHE_SIZE) {
- clear_page_dirty(page);
+ pos += nres;
+ fuse_write_update_size(inode, pos);
+ if (count == PAGE_CACHE_SIZE)
SetPageUptodate(page);
- }
}
fuse_invalidate_attr(inode);
- return err;
+ return err ? err : nres;
}
-static void fuse_release_user_pages(struct fuse_req *req, int write)
+static int fuse_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
+{
+ struct inode *inode = mapping->host;
+ int res = 0;
+
+ if (copied)
+ res = fuse_buffered_write(file, inode, pos, copied, page);
+
+ unlock_page(page);
+ page_cache_release(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, pos, count, NULL);
+
+ offset = req->page_offset;
+ count = res;
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
- if (write)
- set_page_dirty_lock(page);
- put_page(page);
+
+ 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 int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
- unsigned nbytes, int write)
+static ssize_t fuse_fill_write_pages(struct fuse_req *req,
+ struct address_space *mapping,
+ struct iov_iter *ii, loff_t pos)
{
- unsigned long user_addr = (unsigned long) buf;
- unsigned offset = user_addr & ~PAGE_MASK;
- int npages;
+ struct fuse_conn *fc = get_fuse_conn(mapping->host);
+ unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+ size_t count = 0;
+ int err;
+
+ req->in.argpages = 1;
+ req->page_offset = offset;
- /* This doesn't work with nfsd */
- if (!current->mm)
- return -EPERM;
+ 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));
- 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);
- down_read(¤t->mm->mmap_sem);
- npages = get_user_pages(current, current->mm, user_addr, npages, write,
- 0, req->pages, NULL);
- up_read(¤t->mm->mmap_sem);
- if (npages < 0)
- return npages;
+ bytes = min_t(size_t, bytes, fc->max_write - count);
- req->num_pages = npages;
- req->page_offset = offset;
- return 0;
+ again:
+ err = -EFAULT;
+ if (iov_iter_fault_in_readable(ii, bytes))
+ break;
+
+ err = -ENOMEM;
+ page = grab_cache_page_write_begin(mapping, index, 0);
+ if (!page)
+ break;
+
+ if (mapping_writably_mapped(mapping))
+ flush_dcache_page(page);
+
+ 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_direct_io(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos, int write)
+static ssize_t fuse_perform_write(struct file *file,
+ struct address_space *mapping,
+ struct iov_iter *ii, loff_t pos)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
- size_t nmax = write ? fc->max_write : fc->max_read;
- loff_t pos = *ppos;
+ int err = 0;
ssize_t res = 0;
- struct fuse_req *req;
if (is_bad_inode(inode))
return -EIO;
- req = fuse_get_req(fc);
- if (IS_ERR(req))
- return PTR_ERR(req);
+ do {
+ struct fuse_req *req;
+ ssize_t count;
- while (count) {
- size_t nres;
- size_t nbytes = min(count, nmax);
- int err = fuse_get_user_pages(req, buf, nbytes, !write);
- if (err) {
- res = err;
+ req = fuse_get_req(fc);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
break;
}
- nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
- nbytes = min(count, nbytes);
- 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;
+
+ 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 = file_remove_suid(file);
+ 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;
+
+ 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,
+ size_t *nbytesp, int write)
+{
+ size_t nbytes = *nbytesp;
+ unsigned long user_addr = (unsigned long) buf;
+ unsigned offset = user_addr & ~PAGE_MASK;
+ int npages;
+
+ /* 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_t(size_t, nbytes, 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(¤t->mm->mmap_sem);
+ npages = get_user_pages(current, current->mm, user_addr, npages, !write,
+ 0, req->pages, NULL);
+ up_read(¤t->mm->mmap_sem);
+ if (npages < 0)
+ return npages;
+
+ 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;
+}
+
+ssize_t fuse_direct_io(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos, int write)
+{
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
+ size_t nmax = write ? fc->max_write : fc->max_read;
+ loff_t pos = *ppos;
+ ssize_t res = 0;
+ struct fuse_req *req;
+
+ req = fuse_get_req(fc);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ while (count) {
+ size_t nres;
+ fl_owner_t owner = current->files;
+ size_t nbytes = min(count, nmax);
+ int err = fuse_get_user_pages(req, buf, &nbytes, write);
+ if (err) {
+ res = err;
+ break;
+ }
+
+ if (write)
+ nres = fuse_send_write(req, file, pos, nbytes, owner);
+ else
+ nres = fuse_send_read(req, file, pos, nbytes, owner);
+
+ 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;
break;
}
}
- fuse_put_request(fc, req);
- if (res > 0) {
- if (write && pos > i_size_read(inode))
- i_size_write(inode, pos);
+ if (!IS_ERR(req))
+ fuse_put_request(fc, req);
+ if (res > 0)
*ppos = pos;
- }
- fuse_invalidate_attr(inode);
return res;
}
+EXPORT_SYMBOL_GPL(fuse_direct_io);
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);
+ ssize_t res;
+ struct inode *inode = file->f_path.dentry->d_inode;
+
+ if (is_bad_inode(inode))
+ return -EIO;
+
+ res = fuse_direct_io(file, buf, count, ppos, 0);
+
+ fuse_invalidate_attr(inode);
+
+ return res;
}
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;
+ struct inode *inode = file->f_path.dentry->d_inode;
ssize_t res;
+
+ if (is_bad_inode(inode))
+ return -EIO;
+
/* Don't allow parallel writes to the same file */
mutex_lock(&inode->i_mutex);
- res = fuse_direct_io(file, buf, count, ppos, 1);
+ res = generic_write_checks(file, ppos, &count, 0);
+ if (!res) {
+ res = fuse_direct_io(file, buf, count, ppos, 1);
+ if (res > 0)
+ fuse_write_update_size(inode, *ppos);
+ }
mutex_unlock(&inode->i_mutex);
+
+ fuse_invalidate_attr(inode);
+
return res;
}
-static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
+static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
{
- if ((vma->vm_flags & VM_SHARED)) {
- if ((vma->vm_flags & VM_WRITE))
- return -ENODEV;
- else
- vma->vm_flags &= ~VM_MAYWRITE;
+ __free_page(req->pages[0]);
+ fuse_file_put(req->ff);
+}
+
+static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct inode *inode = req->inode;
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info;
+
+ list_del(&req->writepages_entry);
+ dec_bdi_stat(bdi, BDI_WRITEBACK);
+ dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP);
+ bdi_writeout_inc(bdi);
+ wake_up(&fi->page_waitq);
+}
+
+/* Called under fc->lock, may release and reacquire it */
+static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req)
+__releases(&fc->lock)
+__acquires(&fc->lock)
+{
+ struct fuse_inode *fi = get_fuse_inode(req->inode);
+ loff_t size = i_size_read(req->inode);
+ struct fuse_write_in *inarg = &req->misc.write.in;
+
+ if (!fc->connected)
+ goto out_free;
+
+ if (inarg->offset + PAGE_CACHE_SIZE <= size) {
+ inarg->size = PAGE_CACHE_SIZE;
+ } else if (inarg->offset < size) {
+ inarg->size = size & (PAGE_CACHE_SIZE - 1);
+ } else {
+ /* Got truncated off completely */
+ goto out_free;
}
- return generic_file_mmap(file, vma);
+
+ req->in.args[1].size = inarg->size;
+ fi->writectr++;
+ fuse_request_send_background_locked(fc, req);
+ return;
+
+ out_free:
+ fuse_writepage_finish(fc, req);
+ spin_unlock(&fc->lock);
+ fuse_writepage_free(fc, req);
+ fuse_put_request(fc, req);
+ spin_lock(&fc->lock);
+}
+
+/*
+ * If fi->writectr is positive (no truncate or fsync going on) send
+ * all queued writepage requests.
+ *
+ * Called with fc->lock
+ */
+void fuse_flush_writepages(struct inode *inode)
+__releases(&fc->lock)
+__acquires(&fc->lock)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_req *req;
+
+ while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) {
+ req = list_entry(fi->queued_writes.next, struct fuse_req, list);
+ list_del_init(&req->list);
+ fuse_send_writepage(fc, req);
+ }
+}
+
+static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req)
+{
+ struct inode *inode = req->inode;
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ mapping_set_error(inode->i_mapping, req->out.h.error);
+ spin_lock(&fc->lock);
+ fi->writectr--;
+ fuse_writepage_finish(fc, req);
+ spin_unlock(&fc->lock);
+ fuse_writepage_free(fc, req);
+}
+
+static int fuse_writepage_locked(struct page *page)
+{
+ struct address_space *mapping = page->mapping;
+ struct inode *inode = mapping->host;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_req *req;
+ struct fuse_file *ff;
+ struct page *tmp_page;
+
+ set_page_writeback(page);
+
+ req = fuse_request_alloc_nofs();
+ if (!req)
+ goto err;
+
+ tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+ if (!tmp_page)
+ goto err_free;
+
+ spin_lock(&fc->lock);
+ BUG_ON(list_empty(&fi->write_files));
+ ff = list_entry(fi->write_files.next, struct fuse_file, write_entry);
+ req->ff = fuse_file_get(ff);
+ spin_unlock(&fc->lock);
+
+ fuse_write_fill(req, ff, page_offset(page), 0);
+
+ copy_highpage(tmp_page, page);
+ req->misc.write.in.write_flags |= FUSE_WRITE_CACHE;
+ req->in.argpages = 1;
+ req->num_pages = 1;
+ req->pages[0] = tmp_page;
+ req->page_offset = 0;
+ req->end = fuse_writepage_end;
+ req->inode = inode;
+
+ inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK);
+ inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
+ end_page_writeback(page);
+
+ spin_lock(&fc->lock);
+ list_add(&req->writepages_entry, &fi->writepages);
+ list_add_tail(&req->list, &fi->queued_writes);
+ fuse_flush_writepages(inode);
+ spin_unlock(&fc->lock);
+
+ return 0;
+
+err_free:
+ fuse_request_free(req);
+err:
+ end_page_writeback(page);
+ return -ENOMEM;
+}
+
+static int fuse_writepage(struct page *page, struct writeback_control *wbc)
+{
+ int err;
+
+ err = fuse_writepage_locked(page);
+ unlock_page(page);
+
+ return err;
}
-static int fuse_set_page_dirty(struct page *page)
+static int fuse_launder_page(struct page *page)
+{
+ int err = 0;
+ if (clear_page_dirty_for_io(page)) {
+ struct inode *inode = page->mapping->host;
+ err = fuse_writepage_locked(page);
+ if (!err)
+ fuse_wait_on_page_writeback(inode, page->index);
+ }
+ return err;
+}
+
+/*
+ * Write back dirty pages now, because there may not be any suitable
+ * open files later
+ */
+static void fuse_vma_close(struct vm_area_struct *vma)
+{
+ filemap_write_and_wait(vma->vm_file->f_mapping);
+}
+
+/*
+ * Wait for writeback against this page to complete before allowing it
+ * to be marked dirty again, and hence written back again, possibly
+ * before the previous writepage completed.
+ *
+ * Block here, instead of in ->writepage(), so that the userspace fs
+ * can only block processes actually operating on the filesystem.
+ *
+ * Otherwise unprivileged userspace fs would be able to block
+ * unrelated:
+ *
+ * - page migration
+ * - sync(2)
+ * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER
+ */
+static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
- printk("fuse_set_page_dirty: should not happen\n");
- dump_stack();
+ struct page *page = vmf->page;
+ /*
+ * Don't use page->mapping as it may become NULL from a
+ * concurrent truncate.
+ */
+ struct inode *inode = vma->vm_file->f_mapping->host;
+
+ fuse_wait_on_page_writeback(inode, page->index);
return 0;
}
+static const struct vm_operations_struct fuse_file_vm_ops = {
+ .close = fuse_vma_close,
+ .fault = filemap_fault,
+ .page_mkwrite = fuse_page_mkwrite,
+};
+
+static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) {
+ struct inode *inode = file->f_dentry->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_file *ff = file->private_data;
+ /*
+ * file may be written through mmap, so chain it onto the
+ * inodes's write_file list
+ */
+ spin_lock(&fc->lock);
+ if (list_empty(&ff->write_entry))
+ list_add(&ff->write_entry, &fi->write_files);
+ spin_unlock(&fc->lock);
+ }
+ file_accessed(file);
+ vma->vm_ops = &fuse_file_vm_ops;
+ 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;
+
+ invalidate_inode_pages2(file->f_mapping);
+
+ return generic_file_mmap(file, vma);
+}
+
static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
struct file_lock *fl)
{
}
static void fuse_lk_fill(struct fuse_req *req, struct file *file,
- const struct file_lock *fl, int opcode, pid_t pid)
+ const struct file_lock *fl, int opcode, pid_t pid,
+ int flock)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_file *ff = file->private_data;
struct fuse_lk_in *arg = &req->misc.lk_in;
arg->fh = ff->fh;
- arg->owner = fuse_lock_owner_id(fl->fl_owner);
+ arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
arg->lk.start = fl->fl_start;
arg->lk.end = fl->fl_end;
arg->lk.type = fl->fl_type;
arg->lk.pid = pid;
+ if (flock)
+ arg->lk_flags |= FUSE_LK_FLOCK;
req->in.h.opcode = opcode;
req->in.h.nodeid = get_node_id(inode);
req->in.numargs = 1;
static int fuse_getlk(struct file *file, struct file_lock *fl)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
struct fuse_lk_out outarg;
if (IS_ERR(req))
return PTR_ERR(req);
- fuse_lk_fill(req, file, fl, FUSE_GETLK, 0);
+ fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0);
req->out.numargs = 1;
req->out.args[0].size = sizeof(outarg);
req->out.args[0].value = &outarg;
- request_send(fc, req);
+ fuse_request_send(fc, req);
err = req->out.h.error;
fuse_put_request(fc, req);
if (!err)
return err;
}
-static int fuse_setlk(struct file *file, struct file_lock *fl)
+static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
int err;
+ if (fl->fl_lmops && fl->fl_lmops->fl_grant) {
+ /* NLM needs asynchronous locks, which we don't support yet */
+ return -ENOLCK;
+ }
+
/* Unlock on close is handled by the flush method */
if (fl->fl_flags & FL_CLOSE)
return 0;
if (IS_ERR(req))
return PTR_ERR(req);
- fuse_lk_fill(req, file, fl, opcode, pid);
- request_send(fc, req);
+ fuse_lk_fill(req, file, fl, opcode, pid, flock);
+ fuse_request_send(fc, req);
err = req->out.h.error;
+ /* locking is restartable */
+ if (err == -EINTR)
+ err = -ERESTARTSYS;
fuse_put_request(fc, req);
return err;
}
static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
{
- struct inode *inode = file->f_dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
int err;
- if (cmd == F_GETLK) {
+ if (cmd == F_CANCELLK) {
+ err = 0;
+ } else if (cmd == F_GETLK) {
if (fc->no_lock) {
- if (!posix_test_lock(file, fl, fl))
- fl->fl_type = F_UNLCK;
+ posix_test_lock(file, fl);
err = 0;
} else
err = fuse_getlk(file, fl);
} else {
if (fc->no_lock)
- err = posix_lock_file_wait(file, fl);
+ err = posix_lock_file(file, fl, NULL);
else
- err = fuse_setlk(file, fl);
+ err = fuse_setlk(file, fl, 0);
}
return err;
}
+static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl)
+{
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ int err;
+
+ if (fc->no_lock) {
+ err = flock_lock_file_wait(file, fl);
+ } else {
+ /* emulate flock with POSIX locks */
+ fl->fl_owner = (fl_owner_t) file;
+ err = fuse_setlk(file, fl, 1);
+ }
+
+ return err;
+}
+
+static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
+{
+ struct inode *inode = mapping->host;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_req *req;
+ struct fuse_bmap_in inarg;
+ struct fuse_bmap_out outarg;
+ int err;
+
+ if (!inode->i_sb->s_bdev || fc->no_bmap)
+ return 0;
+
+ req = fuse_get_req(fc);
+ if (IS_ERR(req))
+ return 0;
+
+ memset(&inarg, 0, sizeof(inarg));
+ inarg.block = block;
+ inarg.blocksize = inode->i_sb->s_blocksize;
+ req->in.h.opcode = FUSE_BMAP;
+ req->in.h.nodeid = get_node_id(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;
+ fuse_request_send(fc, req);
+ err = req->out.h.error;
+ fuse_put_request(fc, req);
+ if (err == -ENOSYS)
+ fc->no_bmap = 1;
+
+ 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:
+ retval = fuse_update_attributes(inode, NULL, file, NULL);
+ if (retval)
+ goto exit;
+ 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;
+ }
+exit:
+ mutex_unlock(&inode->i_mutex);
+ return retval;
+}
+
+static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov,
+ unsigned int nr_segs, size_t bytes, bool to_user)
+{
+ struct iov_iter ii;
+ int page_idx = 0;
+
+ if (!bytes)
+ return 0;
+
+ iov_iter_init(&ii, iov, nr_segs, bytes, 0);
+
+ while (iov_iter_count(&ii)) {
+ struct page *page = pages[page_idx++];
+ size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii));
+ void *kaddr, *map;
+
+ kaddr = map = kmap(page);
+
+ while (todo) {
+ char __user *uaddr = ii.iov->iov_base + ii.iov_offset;
+ size_t iov_len = ii.iov->iov_len - ii.iov_offset;
+ size_t copy = min(todo, iov_len);
+ size_t left;
+
+ if (!to_user)
+ left = copy_from_user(kaddr, uaddr, copy);
+ else
+ left = copy_to_user(uaddr, kaddr, copy);
+
+ if (unlikely(left))
+ return -EFAULT;
+
+ iov_iter_advance(&ii, copy);
+ todo -= copy;
+ kaddr += copy;
+ }
+
+ kunmap(page);
+ }
+
+ return 0;
+}
+
+/*
+ * For ioctls, there is no generic way to determine how much memory
+ * needs to be read and/or written. Furthermore, ioctls are allowed
+ * to dereference the passed pointer, so the parameter requires deep
+ * copying but FUSE has no idea whatsoever about what to copy in or
+ * out.
+ *
+ * This is solved by allowing FUSE server to retry ioctl with
+ * necessary in/out iovecs. Let's assume the ioctl implementation
+ * needs to read in the following structure.
+ *
+ * struct a {
+ * char *buf;
+ * size_t buflen;
+ * }
+ *
+ * On the first callout to FUSE server, inarg->in_size and
+ * inarg->out_size will be NULL; then, the server completes the ioctl
+ * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
+ * the actual iov array to
+ *
+ * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
+ *
+ * which tells FUSE to copy in the requested area and retry the ioctl.
+ * On the second round, the server has access to the structure and
+ * from that it can tell what to look for next, so on the invocation,
+ * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
+ *
+ * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
+ * { .iov_base = a.buf, .iov_len = a.buflen } }
+ *
+ * FUSE will copy both struct a and the pointed buffer from the
+ * process doing the ioctl and retry ioctl with both struct a and the
+ * buffer.
+ *
+ * This time, FUSE server has everything it needs and completes ioctl
+ * without FUSE_IOCTL_RETRY which finishes the ioctl call.
+ *
+ * Copying data out works the same way.
+ *
+ * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
+ * automatically initializes in and out iovs by decoding @cmd with
+ * _IOC_* macros and the server is not allowed to request RETRY. This
+ * limits ioctl data transfers to well-formed ioctls and is the forced
+ * behavior for all FUSE servers.
+ */
+long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
+ unsigned int flags)
+{
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
+ struct fuse_ioctl_in inarg = {
+ .fh = ff->fh,
+ .cmd = cmd,
+ .arg = arg,
+ .flags = flags
+ };
+ struct fuse_ioctl_out outarg;
+ struct fuse_req *req = NULL;
+ struct page **pages = NULL;
+ struct page *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;
+ int err;
+
+ /* assume all the iovs returned by client always fits in a page */
+ BUILD_BUG_ON(sizeof(struct iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
+
+ err = -ENOMEM;
+ pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL);
+ iov_page = alloc_page(GFP_KERNEL);
+ if (!pages || !iov_page)
+ goto out;
+
+ /*
+ * If restricted, initialize IO parameters as encoded in @cmd.
+ * RETRY from server is not allowed.
+ */
+ if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
+ struct iovec *iov = page_address(iov_page);
+
+ iov->iov_base = (void __user *)arg;
+ iov->iov_len = _IOC_SIZE(cmd);
+
+ if (_IOC_DIR(cmd) & _IOC_WRITE) {
+ in_iov = iov;
+ in_iovs = 1;
+ }
+
+ if (_IOC_DIR(cmd) & _IOC_READ) {
+ out_iov = iov;
+ out_iovs = 1;
+ }
+ }
+
+ retry:
+ inarg.in_size = in_size = iov_length(in_iov, in_iovs);
+ inarg.out_size = out_size = iov_length(out_iov, out_iovs);
+
+ /*
+ * Out data can be used either for actual out data or iovs,
+ * make sure there always is at least one page.
+ */
+ out_size = max_t(size_t, out_size, PAGE_SIZE);
+ max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
+
+ /* make sure there are enough buffer pages and init request with them */
+ err = -ENOMEM;
+ if (max_pages > FUSE_MAX_PAGES_PER_REQ)
+ goto out;
+ while (num_pages < max_pages) {
+ pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+ if (!pages[num_pages])
+ goto out;
+ num_pages++;
+ }
+
+ req = fuse_get_req(fc);
+ 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;
+
+ /* 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;
+ if (in_size) {
+ req->in.numargs++;
+ req->in.args[1].size = in_size;
+ req->in.argpages = 1;
+
+ err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size,
+ false);
+ if (err)
+ 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;
+
+ 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)
+ goto out;
+
+ /* did it ask for retry? */
+ if (outarg.flags & FUSE_IOCTL_RETRY) {
+ char *vaddr;
+
+ /* no retry if in restricted mode */
+ err = -EIO;
+ if (!(flags & FUSE_IOCTL_UNRESTRICTED))
+ goto out;
+
+ in_iovs = outarg.in_iovs;
+ out_iovs = outarg.out_iovs;
+
+ /*
+ * Make sure things are in boundary, separate checks
+ * are to protect against overflow.
+ */
+ err = -ENOMEM;
+ if (in_iovs > FUSE_IOCTL_MAX_IOV ||
+ out_iovs > FUSE_IOCTL_MAX_IOV ||
+ in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
+ goto out;
+
+ err = -EIO;
+ if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred)
+ goto out;
+
+ /* okay, copy in iovs and retry */
+ vaddr = kmap_atomic(pages[0], KM_USER0);
+ memcpy(page_address(iov_page), vaddr, transferred);
+ kunmap_atomic(vaddr, KM_USER0);
+
+ in_iov = page_address(iov_page);
+ out_iov = in_iov + in_iovs;
+
+ goto retry;
+ }
+
+ err = -EIO;
+ if (transferred > inarg.out_size)
+ goto out;
+
+ err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true);
+ out:
+ if (req)
+ fuse_put_request(fc, req);
+ if (iov_page)
+ __free_page(iov_page);
+ while (num_pages)
+ __free_page(pages[--num_pages]);
+ kfree(pages);
+
+ return err ? err : outarg.result;
+}
+EXPORT_SYMBOL_GPL(fuse_do_ioctl);
+
+static long fuse_file_ioctl_common(struct file *file, unsigned int cmd,
+ unsigned long arg, unsigned int flags)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(inode);
+
+ if (!fuse_allow_task(fc, current))
+ return -EACCES;
+
+ if (is_bad_inode(inode))
+ return -EIO;
+
+ return fuse_do_ioctl(file, cmd, arg, flags);
+}
+
+static long fuse_file_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ return fuse_file_ioctl_common(file, cmd, arg, 0);
+}
+
+static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ return fuse_file_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
+}
+
+/*
+ * All files which have been polled are linked to RB tree
+ * fuse_conn->polled_files which is indexed by kh. Walk the tree and
+ * find the matching one.
+ */
+static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh,
+ struct rb_node **parent_out)
+{
+ struct rb_node **link = &fc->polled_files.rb_node;
+ struct rb_node *last = NULL;
+
+ while (*link) {
+ struct fuse_file *ff;
+
+ last = *link;
+ ff = rb_entry(last, struct fuse_file, polled_node);
+
+ if (kh < ff->kh)
+ link = &last->rb_left;
+ else if (kh > ff->kh)
+ link = &last->rb_right;
+ else
+ return link;
+ }
+
+ if (parent_out)
+ *parent_out = last;
+ return link;
+}
+
+/*
+ * The file is about to be polled. Make sure it's on the polled_files
+ * RB tree. Note that files once added to the polled_files tree are
+ * not removed before the file is released. This is because a file
+ * polled once is likely to be polled again.
+ */
+static void fuse_register_polled_file(struct fuse_conn *fc,
+ struct fuse_file *ff)
+{
+ spin_lock(&fc->lock);
+ if (RB_EMPTY_NODE(&ff->polled_node)) {
+ struct rb_node **link, *parent;
+
+ link = fuse_find_polled_node(fc, ff->kh, &parent);
+ BUG_ON(*link);
+ rb_link_node(&ff->polled_node, parent, link);
+ rb_insert_color(&ff->polled_node, &fc->polled_files);
+ }
+ spin_unlock(&fc->lock);
+}
+
+unsigned fuse_file_poll(struct file *file, poll_table *wait)
+{
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fc;
+ struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh };
+ struct fuse_poll_out outarg;
+ struct fuse_req *req;
+ int err;
+
+ if (fc->no_poll)
+ return DEFAULT_POLLMASK;
+
+ poll_wait(file, &ff->poll_wait, wait);
+
+ /*
+ * Ask for notification iff there's someone waiting for it.
+ * The client may ignore the flag and always notify.
+ */
+ if (waitqueue_active(&ff->poll_wait)) {
+ inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY;
+ fuse_register_polled_file(fc, ff);
+ }
+
+ req = fuse_get_req(fc);
+ if (IS_ERR(req))
+ return POLLERR;
+
+ req->in.h.opcode = FUSE_POLL;
+ req->in.h.nodeid = ff->nodeid;
+ 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;
+ fuse_request_send(fc, req);
+ err = req->out.h.error;
+ fuse_put_request(fc, req);
+
+ if (!err)
+ return outarg.revents;
+ if (err == -ENOSYS) {
+ fc->no_poll = 1;
+ return DEFAULT_POLLMASK;
+ }
+ return POLLERR;
+}
+EXPORT_SYMBOL_GPL(fuse_file_poll);
+
+/*
+ * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and
+ * wakes up the poll waiters.
+ */
+int fuse_notify_poll_wakeup(struct fuse_conn *fc,
+ struct fuse_notify_poll_wakeup_out *outarg)
+{
+ u64 kh = outarg->kh;
+ struct rb_node **link;
+
+ spin_lock(&fc->lock);
+
+ link = fuse_find_polled_node(fc, kh, NULL);
+ if (*link) {
+ struct fuse_file *ff;
+
+ ff = rb_entry(*link, struct fuse_file, polled_node);
+ wake_up_interruptible_sync(&ff->poll_wait);
+ }
+
+ spin_unlock(&fc->lock);
+ return 0;
+}
+
static const struct file_operations fuse_file_operations = {
- .llseek = generic_file_llseek,
- .read = generic_file_read,
- .write = generic_file_write,
+ .llseek = fuse_file_llseek,
+ .read = do_sync_read,
+ .aio_read = fuse_file_aio_read,
+ .write = do_sync_write,
+ .aio_write = fuse_file_aio_write,
.mmap = fuse_file_mmap,
.open = fuse_open,
.flush = fuse_flush,
.release = fuse_release,
.fsync = fuse_fsync,
.lock = fuse_file_lock,
- .sendfile = generic_file_sendfile,
+ .flock = fuse_file_flock,
+ .splice_read = generic_file_splice_read,
+ .unlocked_ioctl = fuse_file_ioctl,
+ .compat_ioctl = fuse_file_compat_ioctl,
+ .poll = fuse_file_poll,
};
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,
+ .mmap = fuse_direct_mmap,
.open = fuse_open,
.flush = fuse_flush,
.release = fuse_release,
.fsync = fuse_fsync,
.lock = fuse_file_lock,
- /* no mmap and sendfile */
+ .flock = fuse_file_flock,
+ .unlocked_ioctl = fuse_file_ioctl,
+ .compat_ioctl = fuse_file_compat_ioctl,
+ .poll = fuse_file_poll,
+ /* no splice_read */
};
-static struct address_space_operations fuse_file_aops = {
+static const struct address_space_operations fuse_file_aops = {
.readpage = fuse_readpage,
- .prepare_write = fuse_prepare_write,
- .commit_write = fuse_commit_write,
+ .writepage = fuse_writepage,
+ .launder_page = fuse_launder_page,
+ .write_begin = fuse_write_begin,
+ .write_end = fuse_write_end,
.readpages = fuse_readpages,
- .set_page_dirty = fuse_set_page_dirty,
+ .set_page_dirty = __set_page_dirty_nobuffers,
+ .bmap = fuse_bmap,
};
void fuse_init_file_inode(struct inode *inode)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff