![Miklos Szeredi](/assets/img/avatar_default.png)
Fuse didn't always call i_size_write() with i_mutex held which caused rare hangs on SMP/32bit. This bug has been present since fuse-2.2, well before being merged into mainline. The simplest solution is to protect i_size_write() with the per-connection spinlock. Using i_mutex for this purpose would require some restructuring of the code and I'm not even sure it's always safe to acquire i_mutex in all places i_size needs to be set. Since most of vmtruncate is already duplicated for other reasons, duplicate the remaining part as well, making all i_size_write() calls internal to fuse. Using i_size_write() was unnecessary in fuse_init_inode(), since this function is only called on a newly created locked inode. Reported by a few people over the years, but special thanks to Dana Henriksen who was persistent enough in helping me debug it. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
800 lines
19 KiB
C
800 lines
19 KiB
C
/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2006 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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static const struct file_operations fuse_direct_io_file_operations;
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static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
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struct fuse_open_out *outargp)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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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 | O_TRUNC);
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req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
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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->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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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(void)
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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 (ff) {
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ff->reserved_req = fuse_request_alloc();
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if (!ff->reserved_req) {
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kfree(ff);
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ff = NULL;
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}
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}
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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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void fuse_finish_open(struct inode *inode, struct file *file,
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struct fuse_file *ff, struct fuse_open_out *outarg)
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{
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if (outarg->open_flags & FOPEN_DIRECT_IO)
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file->f_op = &fuse_direct_io_file_operations;
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if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
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invalidate_inode_pages(inode->i_mapping);
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ff->fh = outarg->fh;
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file->private_data = ff;
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}
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int fuse_open_common(struct inode *inode, struct file *file, int 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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/* 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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/* If opening the root node, no lookup has been performed on
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it, so the attributes must be refreshed */
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if (get_node_id(inode) == FUSE_ROOT_ID) {
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err = fuse_do_getattr(inode);
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if (err)
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return err;
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}
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ff = fuse_file_alloc();
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if (!ff)
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return -ENOMEM;
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err = fuse_send_open(inode, file, isdir, &outarg);
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if (err)
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fuse_file_free(ff);
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else {
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if (isdir)
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outarg.open_flags &= ~FOPEN_DIRECT_IO;
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fuse_finish_open(inode, file, ff, &outarg);
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}
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return err;
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}
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struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
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int opcode)
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{
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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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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 = 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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kfree(ff);
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return req;
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}
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int fuse_release_common(struct inode *inode, struct file *file, int isdir)
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{
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struct fuse_file *ff = file->private_data;
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if (ff) {
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_req *req;
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req = fuse_release_fill(ff, get_node_id(inode), file->f_flags,
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isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
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/* Hold vfsmount and dentry until release is finished */
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req->vfsmount = mntget(file->f_vfsmnt);
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req->dentry = dget(file->f_dentry);
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request_send_background(fc, req);
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}
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/* Return value is ignored by VFS */
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return 0;
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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, 0);
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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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return fuse_release_common(inode, file, 0);
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}
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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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static 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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static int fuse_flush(struct file *file, fl_owner_t id)
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{
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struct inode *inode = file->f_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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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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int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
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int isdir)
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{
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struct inode *inode = de->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_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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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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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, struct dentry *de, int datasync)
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{
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return fuse_fsync_common(file, de, datasync, 0);
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}
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void fuse_read_fill(struct fuse_req *req, struct file *file,
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struct inode *inode, loff_t pos, size_t count, int opcode)
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{
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struct fuse_file *ff = file->private_data;
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struct fuse_read_in *inarg = &req->misc.read_in;
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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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req->in.h.opcode = opcode;
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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(struct fuse_read_in);
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req->in.args[0].value = inarg;
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req->out.argpages = 1;
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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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struct inode *inode, loff_t pos, size_t count)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
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request_send(fc, req);
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return req->out.args[0].size;
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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;
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_req *req;
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int err;
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err = -EIO;
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if (is_bad_inode(inode))
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goto out;
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req = fuse_get_req(fc);
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err = PTR_ERR(req);
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if (IS_ERR(req))
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goto out;
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req->out.page_zeroing = 1;
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req->num_pages = 1;
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req->pages[0] = page;
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fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
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err = req->out.h.error;
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fuse_put_request(fc, req);
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if (!err)
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SetPageUptodate(page);
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fuse_invalidate_attr(inode); /* atime changed */
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out:
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unlock_page(page);
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return err;
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}
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static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
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{
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int i;
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fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
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for (i = 0; i < req->num_pages; i++) {
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struct page *page = req->pages[i];
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if (!req->out.h.error)
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SetPageUptodate(page);
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else
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SetPageError(page);
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unlock_page(page);
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}
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fuse_put_request(fc, req);
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}
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static void fuse_send_readpages(struct fuse_req *req, struct file *file,
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struct inode *inode)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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loff_t pos = page_offset(req->pages[0]);
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size_t count = req->num_pages << PAGE_CACHE_SHIFT;
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req->out.page_zeroing = 1;
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fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
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if (fc->async_read) {
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get_file(file);
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req->file = file;
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req->end = fuse_readpages_end;
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request_send_background(fc, req);
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} else {
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request_send(fc, req);
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fuse_readpages_end(fc, req);
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}
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}
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struct fuse_readpages_data {
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struct fuse_req *req;
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struct file *file;
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struct inode *inode;
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};
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static int fuse_readpages_fill(void *_data, struct page *page)
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{
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struct fuse_readpages_data *data = _data;
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struct fuse_req *req = data->req;
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struct inode *inode = data->inode;
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struct fuse_conn *fc = get_fuse_conn(inode);
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if (req->num_pages &&
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(req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
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(req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
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req->pages[req->num_pages - 1]->index + 1 != page->index)) {
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fuse_send_readpages(req, data->file, inode);
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data->req = req = fuse_get_req(fc);
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if (IS_ERR(req)) {
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unlock_page(page);
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return PTR_ERR(req);
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}
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}
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req->pages[req->num_pages] = page;
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req->num_pages ++;
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return 0;
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}
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static int fuse_readpages(struct file *file, struct address_space *mapping,
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struct list_head *pages, unsigned nr_pages)
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{
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struct inode *inode = mapping->host;
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_readpages_data data;
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int err;
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err = -EIO;
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if (is_bad_inode(inode))
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goto clean_pages_up;
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data.file = file;
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data.inode = inode;
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data.req = fuse_get_req(fc);
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err = PTR_ERR(data.req);
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if (IS_ERR(data.req))
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goto clean_pages_up;
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err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
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if (!err) {
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if (data.req->num_pages)
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fuse_send_readpages(data.req, file, inode);
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else
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fuse_put_request(fc, data.req);
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}
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return err;
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clean_pages_up:
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put_pages_list(pages);
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return err;
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}
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static size_t fuse_send_write(struct fuse_req *req, struct file *file,
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struct inode *inode, loff_t pos, size_t count)
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{
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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_write_in inarg;
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struct fuse_write_out outarg;
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memset(&inarg, 0, sizeof(struct fuse_write_in));
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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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req->in.h.opcode = FUSE_WRITE;
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req->in.h.nodeid = get_node_id(inode);
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req->in.argpages = 1;
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req->in.numargs = 2;
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req->in.args[0].size = sizeof(struct fuse_write_in);
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req->in.args[0].value = &inarg;
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req->in.args[1].size = count;
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req->out.numargs = 1;
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req->out.args[0].size = sizeof(struct fuse_write_out);
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req->out.args[0].value = &outarg;
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request_send(fc, req);
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return outarg.size;
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}
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static int fuse_prepare_write(struct file *file, struct page *page,
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unsigned offset, unsigned to)
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{
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/* No op */
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return 0;
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}
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static int fuse_commit_write(struct file *file, struct page *page,
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unsigned offset, unsigned to)
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{
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int err;
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size_t nres;
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unsigned count = to - offset;
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struct inode *inode = page->mapping->host;
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struct fuse_conn *fc = get_fuse_conn(inode);
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loff_t pos = page_offset(page) + offset;
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struct fuse_req *req;
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if (is_bad_inode(inode))
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return -EIO;
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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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req->num_pages = 1;
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req->pages[0] = page;
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req->page_offset = offset;
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nres = fuse_send_write(req, file, inode, pos, count);
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err = req->out.h.error;
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fuse_put_request(fc, req);
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if (!err && nres != count)
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err = -EIO;
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if (!err) {
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pos += count;
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spin_lock(&fc->lock);
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if (pos > inode->i_size)
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i_size_write(inode, pos);
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spin_unlock(&fc->lock);
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if (offset == 0 && to == PAGE_CACHE_SIZE) {
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clear_page_dirty(page);
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SetPageUptodate(page);
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}
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}
|
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fuse_invalidate_attr(inode);
|
|
return err;
|
|
}
|
|
|
|
static void fuse_release_user_pages(struct fuse_req *req, int write)
|
|
{
|
|
unsigned i;
|
|
|
|
for (i = 0; i < req->num_pages; i++) {
|
|
struct page *page = req->pages[i];
|
|
if (write)
|
|
set_page_dirty_lock(page);
|
|
put_page(page);
|
|
}
|
|
}
|
|
|
|
static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
|
|
unsigned nbytes, int write)
|
|
{
|
|
unsigned long user_addr = (unsigned long) buf;
|
|
unsigned offset = user_addr & ~PAGE_MASK;
|
|
int npages;
|
|
|
|
/* This doesn't work with nfsd */
|
|
if (!current->mm)
|
|
return -EPERM;
|
|
|
|
nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
|
|
npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
npages = min(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;
|
|
|
|
req->num_pages = npages;
|
|
req->page_offset = offset;
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos, int write)
|
|
{
|
|
struct inode *inode = file->f_dentry->d_inode;
|
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
size_t nmax = write ? fc->max_write : fc->max_read;
|
|
loff_t pos = *ppos;
|
|
ssize_t res = 0;
|
|
struct fuse_req *req;
|
|
|
|
if (is_bad_inode(inode))
|
|
return -EIO;
|
|
|
|
req = fuse_get_req(fc);
|
|
if (IS_ERR(req))
|
|
return PTR_ERR(req);
|
|
|
|
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;
|
|
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;
|
|
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;
|
|
}
|
|
}
|
|
fuse_put_request(fc, req);
|
|
if (res > 0) {
|
|
if (write) {
|
|
spin_lock(&fc->lock);
|
|
if (pos > inode->i_size)
|
|
i_size_write(inode, pos);
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
*ppos = pos;
|
|
}
|
|
fuse_invalidate_attr(inode);
|
|
|
|
return res;
|
|
}
|
|
|
|
static ssize_t fuse_direct_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
return fuse_direct_io(file, buf, count, ppos, 0);
|
|
}
|
|
|
|
static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode *inode = file->f_dentry->d_inode;
|
|
ssize_t res;
|
|
/* Don't allow parallel writes to the same file */
|
|
mutex_lock(&inode->i_mutex);
|
|
res = fuse_direct_io(file, buf, count, ppos, 1);
|
|
mutex_unlock(&inode->i_mutex);
|
|
return res;
|
|
}
|
|
|
|
static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
if ((vma->vm_flags & VM_SHARED)) {
|
|
if ((vma->vm_flags & VM_WRITE))
|
|
return -ENODEV;
|
|
else
|
|
vma->vm_flags &= ~VM_MAYWRITE;
|
|
}
|
|
return generic_file_mmap(file, vma);
|
|
}
|
|
|
|
static int fuse_set_page_dirty(struct page *page)
|
|
{
|
|
printk("fuse_set_page_dirty: should not happen\n");
|
|
dump_stack();
|
|
return 0;
|
|
}
|
|
|
|
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)
|
|
{
|
|
struct inode *inode = file->f_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;
|
|
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_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);
|
|
req->out.numargs = 1;
|
|
req->out.args[0].size = sizeof(outarg);
|
|
req->out.args[0].value = &outarg;
|
|
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)
|
|
{
|
|
struct inode *inode = file->f_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;
|
|
|
|
/* 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);
|
|
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 fuse_conn *fc = get_fuse_conn(inode);
|
|
int err;
|
|
|
|
if (cmd == F_GETLK) {
|
|
if (fc->no_lock) {
|
|
if (!posix_test_lock(file, fl, fl))
|
|
fl->fl_type = F_UNLCK;
|
|
err = 0;
|
|
} else
|
|
err = fuse_getlk(file, fl);
|
|
} else {
|
|
if (fc->no_lock)
|
|
err = posix_lock_file_wait(file, fl);
|
|
else
|
|
err = fuse_setlk(file, fl);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations fuse_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = do_sync_read,
|
|
.aio_read = generic_file_aio_read,
|
|
.write = do_sync_write,
|
|
.aio_write = generic_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,
|
|
};
|
|
|
|
static const struct file_operations fuse_direct_io_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = fuse_direct_read,
|
|
.write = fuse_direct_write,
|
|
.open = fuse_open,
|
|
.flush = fuse_flush,
|
|
.release = fuse_release,
|
|
.fsync = fuse_fsync,
|
|
.lock = fuse_file_lock,
|
|
/* no mmap and sendfile */
|
|
};
|
|
|
|
static const struct address_space_operations fuse_file_aops = {
|
|
.readpage = fuse_readpage,
|
|
.prepare_write = fuse_prepare_write,
|
|
.commit_write = fuse_commit_write,
|
|
.readpages = fuse_readpages,
|
|
.set_page_dirty = fuse_set_page_dirty,
|
|
};
|
|
|
|
void fuse_init_file_inode(struct inode *inode)
|
|
{
|
|
inode->i_fop = &fuse_file_operations;
|
|
inode->i_data.a_ops = &fuse_file_aops;
|
|
}
|