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- fix long-standing limitation on open-unlink-fop pattern - add refcount to p9_fid (fixes the above and will allow for more cleanups and simplifications in the future) -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE/IPbcYBuWt0zoYhOq06b7GqY5nAFAl/gWOYACgkQq06b7GqY 5nBcHxAArtfxZ4wGa+OMoWt19UvF0bUeYUYdy75rp6awpXmQyMfMZY9oOrZ9L+St mS3oLd8Mq7MeJQ+iGKPPOX+085aNhRtxjQOiHlv02fi09zVyNqj1vptq+rTRkKZL 8KTs+wYSIX2x1WensDBdohYFiWf87vCWyywpQ/1Vm0585mI8B88N3/H5EpkLbPZn 1bgXkakgd2hS+rKu6vJGV8lCJ8eKOSpQ3WUK0WQhY6ysJEL9dbl00qyNQ4kq2UgI i3CpWC/86297KJOehPmegpVwqTIL5wrCkhQy7sNxDkR9E4Q3VoKTNSrnRDtBI0x/ mRCEnc/2Pf76Zv3LpGXnLFSnDLTQaO842Hla92RZJCcHaDtGDwV9Znq6sZgn+pdV wlEpT383s+7AC/X1EFvLPMr5PHrEM1KW25YEYQI78X2hh8G+utW5p3+vu70b0PyT Z7P9yBW4aU4cZb3XcZZihatZG2P1LxHyjNMmn4YBdUeQuitdiJGc2KwjVyKXi9PX +t6xxI+YAIhu/5I9fRtOoIDQNTjsRRE+4FzRKd2kvxW5Z5sV/bZCf6CHnQ2uKYVP fEMYd0GhjrUABbJPLLdFlBXaV+yigvwKtABDnJ5KSA9NlDSVBGewTRa2I+9DoclL yQS4hELuvQsUNCo4AkICixo9vABt0j1OhXlo+B0WVk8Ilh9Wxpc= =DKlc -----END PGP SIGNATURE----- Merge tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux Pull 9p update from Dominique Martinet: - fix long-standing limitation on open-unlink-fop pattern - add refcount to p9_fid (fixes the above and will allow for more cleanups and simplifications in the future) * tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux: 9p: Remove unnecessary IS_ERR() check 9p: Uninitialized variable in v9fs_writeback_fid() 9p: Fix writeback fid incorrectly being attached to dentry 9p: apply review requests for fid refcounting 9p: add refcount to p9_fid struct fs/9p: search open fids first fs/9p: track open fids fs/9p: fix create-unlink-getattr idiom
730 lines
17 KiB
C
730 lines
17 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/fs/9p/vfs_file.c
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*
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* This file contians vfs file ops for 9P2000.
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*
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* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
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* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <linux/file.h>
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#include <linux/stat.h>
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#include <linux/string.h>
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#include <linux/inet.h>
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#include <linux/list.h>
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#include <linux/pagemap.h>
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#include <linux/utsname.h>
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#include <linux/uaccess.h>
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#include <linux/idr.h>
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#include <linux/uio.h>
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#include <linux/slab.h>
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#include <net/9p/9p.h>
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#include <net/9p/client.h>
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#include "v9fs.h"
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#include "v9fs_vfs.h"
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#include "fid.h"
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#include "cache.h"
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static const struct vm_operations_struct v9fs_file_vm_ops;
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static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
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/**
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* v9fs_file_open - open a file (or directory)
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* @inode: inode to be opened
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* @file: file being opened
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*
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*/
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int v9fs_file_open(struct inode *inode, struct file *file)
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{
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int err;
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struct v9fs_inode *v9inode;
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struct v9fs_session_info *v9ses;
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struct p9_fid *fid, *writeback_fid;
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int omode;
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p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
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v9inode = V9FS_I(inode);
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v9ses = v9fs_inode2v9ses(inode);
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if (v9fs_proto_dotl(v9ses))
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omode = v9fs_open_to_dotl_flags(file->f_flags);
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else
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omode = v9fs_uflags2omode(file->f_flags,
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v9fs_proto_dotu(v9ses));
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fid = file->private_data;
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if (!fid) {
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fid = v9fs_fid_clone(file_dentry(file));
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if (IS_ERR(fid))
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return PTR_ERR(fid);
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err = p9_client_open(fid, omode);
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if (err < 0) {
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p9_client_clunk(fid);
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return err;
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}
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if ((file->f_flags & O_APPEND) &&
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(!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
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generic_file_llseek(file, 0, SEEK_END);
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}
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file->private_data = fid;
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mutex_lock(&v9inode->v_mutex);
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if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
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!v9inode->writeback_fid &&
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((file->f_flags & O_ACCMODE) != O_RDONLY)) {
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/*
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* clone a fid and add it to writeback_fid
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* we do it during open time instead of
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* page dirty time via write_begin/page_mkwrite
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* because we want write after unlink usecase
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* to work.
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*/
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writeback_fid = v9fs_writeback_fid(file_dentry(file));
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if (IS_ERR(fid)) {
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err = PTR_ERR(fid);
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mutex_unlock(&v9inode->v_mutex);
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goto out_error;
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}
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v9inode->writeback_fid = (void *) writeback_fid;
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}
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mutex_unlock(&v9inode->v_mutex);
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if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
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v9fs_cache_inode_set_cookie(inode, file);
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v9fs_open_fid_add(inode, fid);
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return 0;
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out_error:
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p9_client_clunk(file->private_data);
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file->private_data = NULL;
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return err;
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}
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/**
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* v9fs_file_lock - lock a file (or directory)
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* @filp: file to be locked
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* @cmd: lock command
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* @fl: file lock structure
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*
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* Bugs: this looks like a local only lock, we should extend into 9P
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* by using open exclusive
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*/
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static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
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{
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int res = 0;
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struct inode *inode = file_inode(filp);
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p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
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/* No mandatory locks */
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if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
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return -ENOLCK;
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if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
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filemap_write_and_wait(inode->i_mapping);
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invalidate_mapping_pages(&inode->i_data, 0, -1);
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}
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return res;
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}
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static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
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{
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struct p9_flock flock;
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struct p9_fid *fid;
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uint8_t status = P9_LOCK_ERROR;
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int res = 0;
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unsigned char fl_type;
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struct v9fs_session_info *v9ses;
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fid = filp->private_data;
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BUG_ON(fid == NULL);
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if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
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BUG();
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res = locks_lock_file_wait(filp, fl);
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if (res < 0)
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goto out;
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/* convert posix lock to p9 tlock args */
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memset(&flock, 0, sizeof(flock));
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/* map the lock type */
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switch (fl->fl_type) {
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case F_RDLCK:
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flock.type = P9_LOCK_TYPE_RDLCK;
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break;
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case F_WRLCK:
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flock.type = P9_LOCK_TYPE_WRLCK;
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break;
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case F_UNLCK:
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flock.type = P9_LOCK_TYPE_UNLCK;
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break;
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}
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flock.start = fl->fl_start;
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if (fl->fl_end == OFFSET_MAX)
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flock.length = 0;
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else
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flock.length = fl->fl_end - fl->fl_start + 1;
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flock.proc_id = fl->fl_pid;
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flock.client_id = fid->clnt->name;
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if (IS_SETLKW(cmd))
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flock.flags = P9_LOCK_FLAGS_BLOCK;
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v9ses = v9fs_inode2v9ses(file_inode(filp));
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/*
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* if its a blocked request and we get P9_LOCK_BLOCKED as the status
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* for lock request, keep on trying
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*/
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for (;;) {
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res = p9_client_lock_dotl(fid, &flock, &status);
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if (res < 0)
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goto out_unlock;
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if (status != P9_LOCK_BLOCKED)
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break;
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if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
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break;
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if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
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!= 0)
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break;
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/*
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* p9_client_lock_dotl overwrites flock.client_id with the
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* server message, free and reuse the client name
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*/
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if (flock.client_id != fid->clnt->name) {
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kfree(flock.client_id);
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flock.client_id = fid->clnt->name;
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}
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}
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/* map 9p status to VFS status */
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switch (status) {
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case P9_LOCK_SUCCESS:
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res = 0;
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break;
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case P9_LOCK_BLOCKED:
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res = -EAGAIN;
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break;
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default:
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WARN_ONCE(1, "unknown lock status code: %d\n", status);
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fallthrough;
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case P9_LOCK_ERROR:
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case P9_LOCK_GRACE:
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res = -ENOLCK;
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break;
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}
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out_unlock:
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/*
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* incase server returned error for lock request, revert
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* it locally
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*/
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if (res < 0 && fl->fl_type != F_UNLCK) {
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fl_type = fl->fl_type;
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fl->fl_type = F_UNLCK;
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/* Even if this fails we want to return the remote error */
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locks_lock_file_wait(filp, fl);
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fl->fl_type = fl_type;
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}
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if (flock.client_id != fid->clnt->name)
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kfree(flock.client_id);
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out:
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return res;
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}
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static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
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{
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struct p9_getlock glock;
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struct p9_fid *fid;
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int res = 0;
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fid = filp->private_data;
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BUG_ON(fid == NULL);
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posix_test_lock(filp, fl);
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/*
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* if we have a conflicting lock locally, no need to validate
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* with server
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*/
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if (fl->fl_type != F_UNLCK)
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return res;
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/* convert posix lock to p9 tgetlock args */
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memset(&glock, 0, sizeof(glock));
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glock.type = P9_LOCK_TYPE_UNLCK;
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glock.start = fl->fl_start;
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if (fl->fl_end == OFFSET_MAX)
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glock.length = 0;
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else
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glock.length = fl->fl_end - fl->fl_start + 1;
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glock.proc_id = fl->fl_pid;
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glock.client_id = fid->clnt->name;
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res = p9_client_getlock_dotl(fid, &glock);
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if (res < 0)
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goto out;
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/* map 9p lock type to os lock type */
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switch (glock.type) {
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case P9_LOCK_TYPE_RDLCK:
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fl->fl_type = F_RDLCK;
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break;
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case P9_LOCK_TYPE_WRLCK:
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fl->fl_type = F_WRLCK;
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break;
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case P9_LOCK_TYPE_UNLCK:
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fl->fl_type = F_UNLCK;
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break;
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}
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if (glock.type != P9_LOCK_TYPE_UNLCK) {
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fl->fl_start = glock.start;
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if (glock.length == 0)
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fl->fl_end = OFFSET_MAX;
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else
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fl->fl_end = glock.start + glock.length - 1;
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fl->fl_pid = -glock.proc_id;
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}
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out:
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if (glock.client_id != fid->clnt->name)
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kfree(glock.client_id);
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return res;
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}
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/**
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* v9fs_file_lock_dotl - lock a file (or directory)
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* @filp: file to be locked
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* @cmd: lock command
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* @fl: file lock structure
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*
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*/
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static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
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{
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struct inode *inode = file_inode(filp);
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int ret = -ENOLCK;
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p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
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filp, cmd, fl, filp);
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/* No mandatory locks */
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if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
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goto out_err;
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if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
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filemap_write_and_wait(inode->i_mapping);
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invalidate_mapping_pages(&inode->i_data, 0, -1);
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}
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if (IS_SETLK(cmd) || IS_SETLKW(cmd))
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ret = v9fs_file_do_lock(filp, cmd, fl);
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else if (IS_GETLK(cmd))
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ret = v9fs_file_getlock(filp, fl);
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else
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ret = -EINVAL;
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out_err:
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return ret;
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}
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/**
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* v9fs_file_flock_dotl - lock a file
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* @filp: file to be locked
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* @cmd: lock command
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* @fl: file lock structure
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*
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*/
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static int v9fs_file_flock_dotl(struct file *filp, int cmd,
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struct file_lock *fl)
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{
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struct inode *inode = file_inode(filp);
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int ret = -ENOLCK;
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p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
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filp, cmd, fl, filp);
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/* No mandatory locks */
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if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
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goto out_err;
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if (!(fl->fl_flags & FL_FLOCK))
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goto out_err;
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if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
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filemap_write_and_wait(inode->i_mapping);
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invalidate_mapping_pages(&inode->i_data, 0, -1);
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}
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/* Convert flock to posix lock */
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fl->fl_flags |= FL_POSIX;
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fl->fl_flags ^= FL_FLOCK;
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if (IS_SETLK(cmd) | IS_SETLKW(cmd))
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ret = v9fs_file_do_lock(filp, cmd, fl);
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else
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ret = -EINVAL;
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out_err:
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return ret;
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}
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/**
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* v9fs_file_read - read from a file
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* @filp: file pointer to read
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* @udata: user data buffer to read data into
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* @count: size of buffer
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* @offset: offset at which to read data
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*
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*/
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static ssize_t
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v9fs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
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{
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struct p9_fid *fid = iocb->ki_filp->private_data;
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int ret, err = 0;
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p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n",
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iov_iter_count(to), iocb->ki_pos);
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if (iocb->ki_filp->f_flags & O_NONBLOCK)
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ret = p9_client_read_once(fid, iocb->ki_pos, to, &err);
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else
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ret = p9_client_read(fid, iocb->ki_pos, to, &err);
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if (!ret)
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return err;
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iocb->ki_pos += ret;
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return ret;
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}
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/**
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* v9fs_file_write - write to a file
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* @filp: file pointer to write
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* @data: data buffer to write data from
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* @count: size of buffer
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* @offset: offset at which to write data
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*
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*/
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static ssize_t
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v9fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
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{
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struct file *file = iocb->ki_filp;
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ssize_t retval;
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loff_t origin;
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int err = 0;
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retval = generic_write_checks(iocb, from);
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if (retval <= 0)
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return retval;
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origin = iocb->ki_pos;
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retval = p9_client_write(file->private_data, iocb->ki_pos, from, &err);
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if (retval > 0) {
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struct inode *inode = file_inode(file);
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loff_t i_size;
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unsigned long pg_start, pg_end;
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pg_start = origin >> PAGE_SHIFT;
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pg_end = (origin + retval - 1) >> PAGE_SHIFT;
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if (inode->i_mapping && inode->i_mapping->nrpages)
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invalidate_inode_pages2_range(inode->i_mapping,
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pg_start, pg_end);
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iocb->ki_pos += retval;
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i_size = i_size_read(inode);
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if (iocb->ki_pos > i_size) {
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inode_add_bytes(inode, iocb->ki_pos - i_size);
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/*
|
|
* Need to serialize against i_size_write() in
|
|
* v9fs_stat2inode()
|
|
*/
|
|
v9fs_i_size_write(inode, iocb->ki_pos);
|
|
}
|
|
return retval;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
|
|
int datasync)
|
|
{
|
|
struct p9_fid *fid;
|
|
struct inode *inode = filp->f_mapping->host;
|
|
struct p9_wstat wstat;
|
|
int retval;
|
|
|
|
retval = file_write_and_wait_range(filp, start, end);
|
|
if (retval)
|
|
return retval;
|
|
|
|
inode_lock(inode);
|
|
p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
|
|
|
|
fid = filp->private_data;
|
|
v9fs_blank_wstat(&wstat);
|
|
|
|
retval = p9_client_wstat(fid, &wstat);
|
|
inode_unlock(inode);
|
|
|
|
return retval;
|
|
}
|
|
|
|
int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
|
|
int datasync)
|
|
{
|
|
struct p9_fid *fid;
|
|
struct inode *inode = filp->f_mapping->host;
|
|
int retval;
|
|
|
|
retval = file_write_and_wait_range(filp, start, end);
|
|
if (retval)
|
|
return retval;
|
|
|
|
inode_lock(inode);
|
|
p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
|
|
|
|
fid = filp->private_data;
|
|
|
|
retval = p9_client_fsync(fid, datasync);
|
|
inode_unlock(inode);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int
|
|
v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
int retval;
|
|
|
|
|
|
retval = generic_file_mmap(filp, vma);
|
|
if (!retval)
|
|
vma->vm_ops = &v9fs_file_vm_ops;
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int
|
|
v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
int retval;
|
|
struct inode *inode;
|
|
struct v9fs_inode *v9inode;
|
|
struct p9_fid *fid;
|
|
|
|
inode = file_inode(filp);
|
|
v9inode = V9FS_I(inode);
|
|
mutex_lock(&v9inode->v_mutex);
|
|
if (!v9inode->writeback_fid &&
|
|
(vma->vm_flags & VM_SHARED) &&
|
|
(vma->vm_flags & VM_WRITE)) {
|
|
/*
|
|
* clone a fid and add it to writeback_fid
|
|
* we do it during mmap instead of
|
|
* page dirty time via write_begin/page_mkwrite
|
|
* because we want write after unlink usecase
|
|
* to work.
|
|
*/
|
|
fid = v9fs_writeback_fid(file_dentry(filp));
|
|
if (IS_ERR(fid)) {
|
|
retval = PTR_ERR(fid);
|
|
mutex_unlock(&v9inode->v_mutex);
|
|
return retval;
|
|
}
|
|
v9inode->writeback_fid = (void *) fid;
|
|
}
|
|
mutex_unlock(&v9inode->v_mutex);
|
|
|
|
retval = generic_file_mmap(filp, vma);
|
|
if (!retval)
|
|
vma->vm_ops = &v9fs_mmap_file_vm_ops;
|
|
|
|
return retval;
|
|
}
|
|
|
|
static vm_fault_t
|
|
v9fs_vm_page_mkwrite(struct vm_fault *vmf)
|
|
{
|
|
struct v9fs_inode *v9inode;
|
|
struct page *page = vmf->page;
|
|
struct file *filp = vmf->vma->vm_file;
|
|
struct inode *inode = file_inode(filp);
|
|
|
|
|
|
p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
|
|
page, (unsigned long)filp->private_data);
|
|
|
|
/* Update file times before taking page lock */
|
|
file_update_time(filp);
|
|
|
|
v9inode = V9FS_I(inode);
|
|
/* make sure the cache has finished storing the page */
|
|
v9fs_fscache_wait_on_page_write(inode, page);
|
|
BUG_ON(!v9inode->writeback_fid);
|
|
lock_page(page);
|
|
if (page->mapping != inode->i_mapping)
|
|
goto out_unlock;
|
|
wait_for_stable_page(page);
|
|
|
|
return VM_FAULT_LOCKED;
|
|
out_unlock:
|
|
unlock_page(page);
|
|
return VM_FAULT_NOPAGE;
|
|
}
|
|
|
|
/**
|
|
* v9fs_mmap_file_read - read from a file
|
|
* @filp: file pointer to read
|
|
* @data: user data buffer to read data into
|
|
* @count: size of buffer
|
|
* @offset: offset at which to read data
|
|
*
|
|
*/
|
|
static ssize_t
|
|
v9fs_mmap_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
/* TODO: Check if there are dirty pages */
|
|
return v9fs_file_read_iter(iocb, to);
|
|
}
|
|
|
|
/**
|
|
* v9fs_mmap_file_write - write to a file
|
|
* @filp: file pointer to write
|
|
* @data: data buffer to write data from
|
|
* @count: size of buffer
|
|
* @offset: offset at which to write data
|
|
*
|
|
*/
|
|
static ssize_t
|
|
v9fs_mmap_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
/*
|
|
* TODO: invalidate mmaps on filp's inode between
|
|
* offset and offset+count
|
|
*/
|
|
return v9fs_file_write_iter(iocb, from);
|
|
}
|
|
|
|
static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
|
|
{
|
|
struct inode *inode;
|
|
|
|
struct writeback_control wbc = {
|
|
.nr_to_write = LONG_MAX,
|
|
.sync_mode = WB_SYNC_ALL,
|
|
.range_start = (loff_t)vma->vm_pgoff * PAGE_SIZE,
|
|
/* absolute end, byte at end included */
|
|
.range_end = (loff_t)vma->vm_pgoff * PAGE_SIZE +
|
|
(vma->vm_end - vma->vm_start - 1),
|
|
};
|
|
|
|
if (!(vma->vm_flags & VM_SHARED))
|
|
return;
|
|
|
|
p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
|
|
|
|
inode = file_inode(vma->vm_file);
|
|
|
|
if (!mapping_can_writeback(inode->i_mapping))
|
|
wbc.nr_to_write = 0;
|
|
|
|
might_sleep();
|
|
sync_inode(inode, &wbc);
|
|
}
|
|
|
|
|
|
static const struct vm_operations_struct v9fs_file_vm_ops = {
|
|
.fault = filemap_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = v9fs_vm_page_mkwrite,
|
|
};
|
|
|
|
static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
|
|
.close = v9fs_mmap_vm_close,
|
|
.fault = filemap_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = v9fs_vm_page_mkwrite,
|
|
};
|
|
|
|
|
|
const struct file_operations v9fs_cached_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = generic_file_read_iter,
|
|
.write_iter = generic_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock,
|
|
.mmap = v9fs_file_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync,
|
|
};
|
|
|
|
const struct file_operations v9fs_cached_file_operations_dotl = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = generic_file_read_iter,
|
|
.write_iter = generic_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock_dotl,
|
|
.flock = v9fs_file_flock_dotl,
|
|
.mmap = v9fs_file_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync_dotl,
|
|
};
|
|
|
|
const struct file_operations v9fs_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = v9fs_file_read_iter,
|
|
.write_iter = v9fs_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock,
|
|
.mmap = generic_file_readonly_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync,
|
|
};
|
|
|
|
const struct file_operations v9fs_file_operations_dotl = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = v9fs_file_read_iter,
|
|
.write_iter = v9fs_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock_dotl,
|
|
.flock = v9fs_file_flock_dotl,
|
|
.mmap = generic_file_readonly_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync_dotl,
|
|
};
|
|
|
|
const struct file_operations v9fs_mmap_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = v9fs_mmap_file_read_iter,
|
|
.write_iter = v9fs_mmap_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock,
|
|
.mmap = v9fs_mmap_file_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync,
|
|
};
|
|
|
|
const struct file_operations v9fs_mmap_file_operations_dotl = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = v9fs_mmap_file_read_iter,
|
|
.write_iter = v9fs_mmap_file_write_iter,
|
|
.open = v9fs_file_open,
|
|
.release = v9fs_dir_release,
|
|
.lock = v9fs_file_lock_dotl,
|
|
.flock = v9fs_file_flock_dotl,
|
|
.mmap = v9fs_mmap_file_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fsync = v9fs_file_fsync_dotl,
|
|
};
|