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![Lucas De Marchi](/assets/img/avatar_default.png)
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2186 lines
52 KiB
C
2186 lines
52 KiB
C
/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
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This program can be distributed under the terms of the GNU GPL.
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See the file COPYING.
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*/
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#include "fuse_i.h"
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#include <linux/pagemap.h>
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#include <linux/slab.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/module.h>
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#include <linux/compat.h>
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static const struct file_operations fuse_direct_io_file_operations;
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static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
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int opcode, struct fuse_open_out *outargp)
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{
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struct fuse_open_in inarg;
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struct fuse_req *req;
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int err;
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req = fuse_get_req(fc);
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if (IS_ERR(req))
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return PTR_ERR(req);
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memset(&inarg, 0, sizeof(inarg));
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inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
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if (!fc->atomic_o_trunc)
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inarg.flags &= ~O_TRUNC;
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req->in.h.opcode = opcode;
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req->in.h.nodeid = nodeid;
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(inarg);
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req->in.args[0].value = &inarg;
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req->out.numargs = 1;
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req->out.args[0].size = sizeof(*outargp);
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req->out.args[0].value = outargp;
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fuse_request_send(fc, req);
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err = req->out.h.error;
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fuse_put_request(fc, req);
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return err;
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}
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struct fuse_file *fuse_file_alloc(struct fuse_conn *fc)
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{
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struct fuse_file *ff;
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ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
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if (unlikely(!ff))
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return NULL;
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ff->fc = fc;
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ff->reserved_req = fuse_request_alloc();
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if (unlikely(!ff->reserved_req)) {
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kfree(ff);
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return NULL;
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}
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INIT_LIST_HEAD(&ff->write_entry);
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atomic_set(&ff->count, 0);
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RB_CLEAR_NODE(&ff->polled_node);
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init_waitqueue_head(&ff->poll_wait);
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spin_lock(&fc->lock);
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ff->kh = ++fc->khctr;
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spin_unlock(&fc->lock);
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return ff;
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}
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void fuse_file_free(struct fuse_file *ff)
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{
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fuse_request_free(ff->reserved_req);
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kfree(ff);
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}
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struct fuse_file *fuse_file_get(struct fuse_file *ff)
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{
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atomic_inc(&ff->count);
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return ff;
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}
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static void fuse_release_async(struct work_struct *work)
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{
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struct fuse_req *req;
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struct fuse_conn *fc;
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struct path path;
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req = container_of(work, struct fuse_req, misc.release.work);
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path = req->misc.release.path;
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fc = get_fuse_conn(path.dentry->d_inode);
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fuse_put_request(fc, req);
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path_put(&path);
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}
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static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
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{
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if (fc->destroy_req) {
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/*
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* If this is a fuseblk mount, then it's possible that
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* releasing the path will result in releasing the
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* super block and sending the DESTROY request. If
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* the server is single threaded, this would hang.
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* For this reason do the path_put() in a separate
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* thread.
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*/
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atomic_inc(&req->count);
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INIT_WORK(&req->misc.release.work, fuse_release_async);
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schedule_work(&req->misc.release.work);
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} else {
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path_put(&req->misc.release.path);
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}
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}
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static void fuse_file_put(struct fuse_file *ff, bool sync)
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{
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if (atomic_dec_and_test(&ff->count)) {
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struct fuse_req *req = ff->reserved_req;
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if (sync) {
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fuse_request_send(ff->fc, req);
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path_put(&req->misc.release.path);
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fuse_put_request(ff->fc, req);
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} else {
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req->end = fuse_release_end;
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fuse_request_send_background(ff->fc, req);
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}
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kfree(ff);
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}
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}
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int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
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bool isdir)
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{
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struct fuse_open_out outarg;
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struct fuse_file *ff;
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int err;
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int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
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ff = fuse_file_alloc(fc);
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if (!ff)
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return -ENOMEM;
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err = fuse_send_open(fc, nodeid, file, opcode, &outarg);
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if (err) {
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fuse_file_free(ff);
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return err;
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}
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if (isdir)
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outarg.open_flags &= ~FOPEN_DIRECT_IO;
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ff->fh = outarg.fh;
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ff->nodeid = nodeid;
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ff->open_flags = outarg.open_flags;
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file->private_data = fuse_file_get(ff);
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return 0;
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}
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EXPORT_SYMBOL_GPL(fuse_do_open);
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void fuse_finish_open(struct inode *inode, struct file *file)
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{
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struct fuse_file *ff = file->private_data;
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struct fuse_conn *fc = get_fuse_conn(inode);
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if (ff->open_flags & FOPEN_DIRECT_IO)
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file->f_op = &fuse_direct_io_file_operations;
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if (!(ff->open_flags & FOPEN_KEEP_CACHE))
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invalidate_inode_pages2(inode->i_mapping);
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if (ff->open_flags & FOPEN_NONSEEKABLE)
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nonseekable_open(inode, file);
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if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
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struct fuse_inode *fi = get_fuse_inode(inode);
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spin_lock(&fc->lock);
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fi->attr_version = ++fc->attr_version;
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i_size_write(inode, 0);
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spin_unlock(&fc->lock);
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fuse_invalidate_attr(inode);
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}
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}
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int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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int err;
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/* VFS checks this, but only _after_ ->open() */
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if (file->f_flags & O_DIRECT)
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return -EINVAL;
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err = generic_file_open(inode, file);
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if (err)
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return err;
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err = fuse_do_open(fc, get_node_id(inode), file, isdir);
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if (err)
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return err;
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fuse_finish_open(inode, file);
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return 0;
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}
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static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode)
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{
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struct fuse_conn *fc = ff->fc;
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struct fuse_req *req = ff->reserved_req;
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struct fuse_release_in *inarg = &req->misc.release.in;
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spin_lock(&fc->lock);
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list_del(&ff->write_entry);
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if (!RB_EMPTY_NODE(&ff->polled_node))
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rb_erase(&ff->polled_node, &fc->polled_files);
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spin_unlock(&fc->lock);
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wake_up_interruptible_all(&ff->poll_wait);
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inarg->fh = ff->fh;
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inarg->flags = flags;
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req->in.h.opcode = opcode;
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req->in.h.nodeid = ff->nodeid;
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(struct fuse_release_in);
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req->in.args[0].value = inarg;
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}
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void fuse_release_common(struct file *file, int opcode)
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{
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struct fuse_file *ff;
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struct fuse_req *req;
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ff = file->private_data;
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if (unlikely(!ff))
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return;
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req = ff->reserved_req;
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fuse_prepare_release(ff, file->f_flags, opcode);
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/* Hold vfsmount and dentry until release is finished */
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path_get(&file->f_path);
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req->misc.release.path = file->f_path;
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/*
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* Normally this will send the RELEASE request, however if
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* some asynchronous READ or WRITE requests are outstanding,
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* the sending will be delayed.
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*
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* Make the release synchronous if this is a fuseblk mount,
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* synchronous RELEASE is allowed (and desirable) in this case
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* because the server can be trusted not to screw up.
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*/
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fuse_file_put(ff, ff->fc->destroy_req != NULL);
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}
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static int fuse_open(struct inode *inode, struct file *file)
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{
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return fuse_open_common(inode, file, false);
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}
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static int fuse_release(struct inode *inode, struct file *file)
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{
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fuse_release_common(file, FUSE_RELEASE);
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/* return value is ignored by VFS */
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return 0;
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}
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void fuse_sync_release(struct fuse_file *ff, int flags)
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{
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WARN_ON(atomic_read(&ff->count) > 1);
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fuse_prepare_release(ff, flags, FUSE_RELEASE);
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ff->reserved_req->force = 1;
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fuse_request_send(ff->fc, ff->reserved_req);
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fuse_put_request(ff->fc, ff->reserved_req);
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kfree(ff);
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}
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EXPORT_SYMBOL_GPL(fuse_sync_release);
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/*
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* Scramble the ID space with XTEA, so that the value of the files_struct
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* pointer is not exposed to userspace.
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*/
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u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
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{
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u32 *k = fc->scramble_key;
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u64 v = (unsigned long) id;
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u32 v0 = v;
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u32 v1 = v >> 32;
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u32 sum = 0;
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int i;
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for (i = 0; i < 32; i++) {
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v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
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sum += 0x9E3779B9;
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v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
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}
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return (u64) v0 + ((u64) v1 << 32);
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}
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/*
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* Check if page is under writeback
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*
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* This is currently done by walking the list of writepage requests
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* for the inode, which can be pretty inefficient.
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*/
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static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_inode *fi = get_fuse_inode(inode);
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struct fuse_req *req;
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bool found = false;
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spin_lock(&fc->lock);
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list_for_each_entry(req, &fi->writepages, writepages_entry) {
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pgoff_t curr_index;
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BUG_ON(req->inode != inode);
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curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT;
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if (curr_index == index) {
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found = true;
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break;
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}
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}
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spin_unlock(&fc->lock);
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return found;
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}
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/*
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* Wait for page writeback to be completed.
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*
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* Since fuse doesn't rely on the VM writeback tracking, this has to
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* use some other means.
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*/
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static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index)
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{
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struct fuse_inode *fi = get_fuse_inode(inode);
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wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index));
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return 0;
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}
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static int fuse_flush(struct file *file, fl_owner_t id)
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{
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struct inode *inode = file->f_path.dentry->d_inode;
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_file *ff = file->private_data;
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struct fuse_req *req;
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struct fuse_flush_in inarg;
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int err;
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if (is_bad_inode(inode))
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return -EIO;
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if (fc->no_flush)
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return 0;
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req = fuse_get_req_nofail(fc, file);
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memset(&inarg, 0, sizeof(inarg));
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inarg.fh = ff->fh;
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inarg.lock_owner = fuse_lock_owner_id(fc, id);
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req->in.h.opcode = FUSE_FLUSH;
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req->in.h.nodeid = get_node_id(inode);
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(inarg);
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req->in.args[0].value = &inarg;
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req->force = 1;
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fuse_request_send(fc, req);
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err = req->out.h.error;
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fuse_put_request(fc, req);
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if (err == -ENOSYS) {
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fc->no_flush = 1;
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err = 0;
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}
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return err;
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}
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/*
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* Wait for all pending writepages on the inode to finish.
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*
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* This is currently done by blocking further writes with FUSE_NOWRITE
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* and waiting for all sent writes to complete.
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*
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* This must be called under i_mutex, otherwise the FUSE_NOWRITE usage
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* could conflict with truncation.
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*/
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static void fuse_sync_writes(struct inode *inode)
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{
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fuse_set_nowrite(inode);
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fuse_release_nowrite(inode);
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}
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int fuse_fsync_common(struct file *file, int datasync, int isdir)
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{
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struct inode *inode = file->f_mapping->host;
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_file *ff = file->private_data;
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struct fuse_req *req;
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struct fuse_fsync_in inarg;
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int err;
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if (is_bad_inode(inode))
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return -EIO;
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if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
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return 0;
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/*
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* Start writeback against all dirty pages of the inode, then
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* wait for all outstanding writes, before sending the FSYNC
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* request.
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*/
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err = write_inode_now(inode, 0);
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if (err)
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return err;
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fuse_sync_writes(inode);
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req = fuse_get_req(fc);
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if (IS_ERR(req))
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return PTR_ERR(req);
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memset(&inarg, 0, sizeof(inarg));
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inarg.fh = ff->fh;
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inarg.fsync_flags = datasync ? 1 : 0;
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req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
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req->in.h.nodeid = get_node_id(inode);
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(inarg);
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req->in.args[0].value = &inarg;
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fuse_request_send(fc, req);
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err = req->out.h.error;
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fuse_put_request(fc, req);
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if (err == -ENOSYS) {
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if (isdir)
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fc->no_fsyncdir = 1;
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else
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fc->no_fsync = 1;
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err = 0;
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}
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return err;
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}
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static int fuse_fsync(struct file *file, int datasync)
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{
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return fuse_fsync_common(file, datasync, 0);
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}
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void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos,
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size_t count, int opcode)
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{
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struct fuse_read_in *inarg = &req->misc.read.in;
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struct fuse_file *ff = file->private_data;
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inarg->fh = ff->fh;
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inarg->offset = pos;
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inarg->size = count;
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inarg->flags = file->f_flags;
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req->in.h.opcode = opcode;
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req->in.h.nodeid = ff->nodeid;
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(struct fuse_read_in);
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req->in.args[0].value = inarg;
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req->out.argvar = 1;
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req->out.numargs = 1;
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req->out.args[0].size = count;
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}
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static size_t fuse_send_read(struct fuse_req *req, struct file *file,
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loff_t pos, size_t count, fl_owner_t owner)
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{
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struct fuse_file *ff = file->private_data;
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struct fuse_conn *fc = ff->fc;
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fuse_read_fill(req, file, pos, count, FUSE_READ);
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if (owner != NULL) {
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struct fuse_read_in *inarg = &req->misc.read.in;
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inarg->read_flags |= FUSE_READ_LOCKOWNER;
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inarg->lock_owner = fuse_lock_owner_id(fc, owner);
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}
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fuse_request_send(fc, req);
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return req->out.args[0].size;
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}
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static void fuse_read_update_size(struct inode *inode, loff_t size,
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u64 attr_ver)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_inode *fi = get_fuse_inode(inode);
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spin_lock(&fc->lock);
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if (attr_ver == fi->attr_version && size < inode->i_size) {
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fi->attr_version = ++fc->attr_version;
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i_size_write(inode, size);
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}
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spin_unlock(&fc->lock);
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}
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static int fuse_readpage(struct file *file, struct page *page)
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{
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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 lifetime 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;
|
|
num_read = fuse_send_read(req, file, pos, count, NULL);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
|
|
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);
|
|
return err;
|
|
}
|
|
|
|
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 address_space *mapping = NULL;
|
|
|
|
for (i = 0; mapping == NULL && i < req->num_pages; i++)
|
|
mapping = req->pages[i]->mapping;
|
|
|
|
if (mapping) {
|
|
struct inode *inode = mapping->host;
|
|
|
|
/*
|
|
* Short read means EOF. If file size is larger, truncate it
|
|
*/
|
|
if (!req->out.h.error && num_read < count) {
|
|
loff_t pos;
|
|
|
|
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];
|
|
if (!req->out.h.error)
|
|
SetPageUptodate(page);
|
|
else
|
|
SetPageError(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
if (req->ff)
|
|
fuse_file_put(req->ff, false);
|
|
}
|
|
|
|
static void fuse_send_readpages(struct fuse_req *req, struct file *file)
|
|
{
|
|
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;
|
|
req->out.page_replace = 1;
|
|
fuse_read_fill(req, file, pos, count, FUSE_READ);
|
|
req->misc.read.attr_ver = fuse_get_attr_version(fc);
|
|
if (fc->async_read) {
|
|
req->ff = fuse_file_get(ff);
|
|
req->end = fuse_readpages_end;
|
|
fuse_request_send_background(fc, req);
|
|
} else {
|
|
fuse_request_send(fc, req);
|
|
fuse_readpages_end(fc, req);
|
|
fuse_put_request(fc, req);
|
|
}
|
|
}
|
|
|
|
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_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);
|
|
data->req = req = fuse_get_req(fc);
|
|
if (IS_ERR(req)) {
|
|
unlock_page(page);
|
|
return PTR_ERR(req);
|
|
}
|
|
}
|
|
page_cache_get(page);
|
|
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_fill_data data;
|
|
int err;
|
|
|
|
err = -EIO;
|
|
if (is_bad_inode(inode))
|
|
goto out;
|
|
|
|
data.file = file;
|
|
data.inode = inode;
|
|
data.req = fuse_get_req(fc);
|
|
err = PTR_ERR(data.req);
|
|
if (IS_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);
|
|
else
|
|
fuse_put_request(fc, data.req);
|
|
}
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos)
|
|
{
|
|
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;
|
|
}
|
|
|
|
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 = ff->nodeid;
|
|
req->in.numargs = 2;
|
|
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;
|
|
}
|
|
|
|
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_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
*pagep = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!*pagep)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
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, pos, count, NULL);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
if (!err && !nres)
|
|
err = -EIO;
|
|
if (!err) {
|
|
pos += nres;
|
|
fuse_write_update_size(inode, pos);
|
|
if (count == PAGE_CACHE_SIZE)
|
|
SetPageUptodate(page);
|
|
}
|
|
fuse_invalidate_attr(inode);
|
|
return err ? err : nres;
|
|
}
|
|
|
|
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 (!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->in.argpages = 1;
|
|
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_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_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 = 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);
|
|
npages = get_user_pages_fast(user_addr, npages, !write, req->pages);
|
|
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;
|
|
res += nres;
|
|
pos += nres;
|
|
buf += nres;
|
|
if (nres != nbytes)
|
|
break;
|
|
if (count) {
|
|
fuse_put_request(fc, req);
|
|
req = fuse_get_req(fc);
|
|
if (IS_ERR(req))
|
|
break;
|
|
}
|
|
}
|
|
if (!IS_ERR(req))
|
|
fuse_put_request(fc, req);
|
|
if (res > 0)
|
|
*ppos = pos;
|
|
|
|
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)
|
|
{
|
|
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_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 = 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 void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
__free_page(req->pages[0]);
|
|
fuse_file_put(req->ff, false);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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_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)
|
|
{
|
|
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)
|
|
{
|
|
switch (ffl->type) {
|
|
case F_UNLCK:
|
|
break;
|
|
|
|
case F_RDLCK:
|
|
case F_WRLCK:
|
|
if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
|
|
ffl->end < ffl->start)
|
|
return -EIO;
|
|
|
|
fl->fl_start = ffl->start;
|
|
fl->fl_end = ffl->end;
|
|
fl->fl_pid = ffl->pid;
|
|
break;
|
|
|
|
default:
|
|
return -EIO;
|
|
}
|
|
fl->fl_type = ffl->type;
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_lk_fill(struct fuse_req *req, struct file *file,
|
|
const struct file_lock *fl, int opcode, pid_t pid,
|
|
int flock)
|
|
{
|
|
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(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;
|
|
req->in.args[0].size = sizeof(*arg);
|
|
req->in.args[0].value = arg;
|
|
}
|
|
|
|
static int fuse_getlk(struct file *file, struct file_lock *fl)
|
|
{
|
|
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;
|
|
int err;
|
|
|
|
req = fuse_get_req(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
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;
|
|
fuse_request_send(fc, req);
|
|
err = req->out.h.error;
|
|
fuse_put_request(fc, req);
|
|
if (!err)
|
|
err = convert_fuse_file_lock(&outarg.lk, fl);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int fuse_setlk(struct file *file, struct file_lock *fl, int flock)
|
|
{
|
|
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;
|
|
|
|
req = fuse_get_req(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(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_path.dentry->d_inode;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
int err;
|
|
|
|
if (cmd == F_CANCELLK) {
|
|
err = 0;
|
|
} else if (cmd == F_GETLK) {
|
|
if (fc->no_lock) {
|
|
posix_test_lock(file, fl);
|
|
err = 0;
|
|
} else
|
|
err = fuse_getlk(file, fl);
|
|
} else {
|
|
if (fc->no_lock)
|
|
err = posix_lock_file(file, fl, NULL);
|
|
else
|
|
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;
|
|
|
|
kaddr = 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;
|
|
}
|
|
|
|
/*
|
|
* CUSE servers compiled on 32bit broke on 64bit kernels because the
|
|
* ABI was defined to be 'struct iovec' which is different on 32bit
|
|
* and 64bit. Fortunately we can determine which structure the server
|
|
* used from the size of the reply.
|
|
*/
|
|
static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
|
|
size_t transferred, unsigned count,
|
|
bool is_compat)
|
|
{
|
|
#ifdef CONFIG_COMPAT
|
|
if (count * sizeof(struct compat_iovec) == transferred) {
|
|
struct compat_iovec *ciov = src;
|
|
unsigned i;
|
|
|
|
/*
|
|
* With this interface a 32bit server cannot support
|
|
* non-compat (i.e. ones coming from 64bit apps) ioctl
|
|
* requests
|
|
*/
|
|
if (!is_compat)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
dst[i].iov_base = compat_ptr(ciov[i].iov_base);
|
|
dst[i].iov_len = ciov[i].iov_len;
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
if (count * sizeof(struct iovec) != transferred)
|
|
return -EIO;
|
|
|
|
memcpy(dst, src, transferred);
|
|
return 0;
|
|
}
|
|
|
|
/* Make sure iov_length() won't overflow */
|
|
static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count)
|
|
{
|
|
size_t n;
|
|
u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT;
|
|
|
|
for (n = 0; n < count; n++) {
|
|
if (iov->iov_len > (size_t) max)
|
|
return -ENOMEM;
|
|
max -= iov->iov_len;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
|
|
void *src, size_t transferred, unsigned count,
|
|
bool is_compat)
|
|
{
|
|
unsigned i;
|
|
struct fuse_ioctl_iovec *fiov = src;
|
|
|
|
if (fc->minor < 16) {
|
|
return fuse_copy_ioctl_iovec_old(dst, src, transferred,
|
|
count, is_compat);
|
|
}
|
|
|
|
if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
|
|
return -EIO;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
/* Did the server supply an inappropriate value? */
|
|
if (fiov[i].base != (unsigned long) fiov[i].base ||
|
|
fiov[i].len != (unsigned long) fiov[i].len)
|
|
return -EIO;
|
|
|
|
dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
|
|
dst[i].iov_len = (size_t) fiov[i].len;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
if (is_compat &&
|
|
(ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
|
|
(compat_size_t) dst[i].iov_len != fiov[i].len))
|
|
return -EIO;
|
|
#endif
|
|
}
|
|
|
|
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 iovec *iov_page = NULL;
|
|
struct iovec *in_iov = NULL, *out_iov = NULL;
|
|
unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages;
|
|
size_t in_size, out_size, transferred;
|
|
int err;
|
|
|
|
#if BITS_PER_LONG == 32
|
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
#else
|
|
if (flags & FUSE_IOCTL_COMPAT)
|
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
#endif
|
|
|
|
/* assume all the iovs returned by client always fits in a page */
|
|
BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
|
|
|
|
err = -ENOMEM;
|
|
pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL);
|
|
iov_page = (struct iovec *) __get_free_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 = 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) {
|
|
void *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;
|
|
|
|
vaddr = kmap_atomic(pages[0], KM_USER0);
|
|
err = fuse_copy_ioctl_iovec(fc, iov_page, vaddr,
|
|
transferred, in_iovs + out_iovs,
|
|
(flags & FUSE_IOCTL_COMPAT) != 0);
|
|
kunmap_atomic(vaddr, KM_USER0);
|
|
if (err)
|
|
goto out;
|
|
|
|
in_iov = iov_page;
|
|
out_iov = in_iov + in_iovs;
|
|
|
|
err = fuse_verify_ioctl_iov(in_iov, in_iovs);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = fuse_verify_ioctl_iov(out_iov, out_iovs);
|
|
if (err)
|
|
goto out;
|
|
|
|
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);
|
|
free_page((unsigned long) 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 = 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,
|
|
.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 = 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,
|
|
.flock = fuse_file_flock,
|
|
.unlocked_ioctl = fuse_file_ioctl,
|
|
.compat_ioctl = fuse_file_compat_ioctl,
|
|
.poll = fuse_file_poll,
|
|
/* no splice_read */
|
|
};
|
|
|
|
static const struct address_space_operations fuse_file_aops = {
|
|
.readpage = fuse_readpage,
|
|
.writepage = fuse_writepage,
|
|
.launder_page = fuse_launder_page,
|
|
.write_begin = fuse_write_begin,
|
|
.write_end = fuse_write_end,
|
|
.readpages = fuse_readpages,
|
|
.set_page_dirty = __set_page_dirty_nobuffers,
|
|
.bmap = fuse_bmap,
|
|
};
|
|
|
|
void fuse_init_file_inode(struct inode *inode)
|
|
{
|
|
inode->i_fop = &fuse_file_operations;
|
|
inode->i_data.a_ops = &fuse_file_aops;
|
|
}
|