From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- fs/coda/psdev.c | 438 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 438 insertions(+) create mode 100644 fs/coda/psdev.c (limited to 'fs/coda/psdev.c') diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c new file mode 100644 index 000000000..3c3148588 --- /dev/null +++ b/fs/coda/psdev.c @@ -0,0 +1,438 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * An implementation of a loadable kernel mode driver providing + * multiple kernel/user space bidirectional communications links. + * + * Author: Alan Cox + * + * Adapted to become the Linux 2.0 Coda pseudo device + * Peter Braam + * Michael Callahan + * + * Changes for Linux 2.1 + * Copyright (c) 1997 Carnegie-Mellon University + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "coda_psdev.h" +#include "coda_linux.h" + +#include "coda_int.h" + +/* statistics */ +int coda_hard; /* allows signals during upcalls */ +unsigned long coda_timeout = 30; /* .. secs, then signals will dequeue */ + + +struct venus_comm coda_comms[MAX_CODADEVS]; +static struct class *coda_psdev_class; + +/* + * Device operations + */ + +static __poll_t coda_psdev_poll(struct file *file, poll_table * wait) +{ + struct venus_comm *vcp = (struct venus_comm *) file->private_data; + __poll_t mask = EPOLLOUT | EPOLLWRNORM; + + poll_wait(file, &vcp->vc_waitq, wait); + mutex_lock(&vcp->vc_mutex); + if (!list_empty(&vcp->vc_pending)) + mask |= EPOLLIN | EPOLLRDNORM; + mutex_unlock(&vcp->vc_mutex); + + return mask; +} + +static long coda_psdev_ioctl(struct file * filp, unsigned int cmd, unsigned long arg) +{ + unsigned int data; + + switch(cmd) { + case CIOC_KERNEL_VERSION: + data = CODA_KERNEL_VERSION; + return put_user(data, (int __user *) arg); + default: + return -ENOTTY; + } + + return 0; +} + +/* + * Receive a message written by Venus to the psdev + */ + +static ssize_t coda_psdev_write(struct file *file, const char __user *buf, + size_t nbytes, loff_t *off) +{ + struct venus_comm *vcp = (struct venus_comm *) file->private_data; + struct upc_req *req = NULL; + struct upc_req *tmp; + struct list_head *lh; + struct coda_in_hdr hdr; + ssize_t retval = 0, count = 0; + int error; + + /* make sure there is enough to copy out the (opcode, unique) values */ + if (nbytes < (2 * sizeof(u_int32_t))) + return -EINVAL; + + /* Peek at the opcode, uniquefier */ + if (copy_from_user(&hdr, buf, 2 * sizeof(u_int32_t))) + return -EFAULT; + + if (DOWNCALL(hdr.opcode)) { + union outputArgs *dcbuf; + int size = sizeof(*dcbuf); + + if ( nbytes < sizeof(struct coda_out_hdr) ) { + pr_warn("coda_downcall opc %d uniq %d, not enough!\n", + hdr.opcode, hdr.unique); + count = nbytes; + goto out; + } + if ( nbytes > size ) { + pr_warn("downcall opc %d, uniq %d, too much!", + hdr.opcode, hdr.unique); + nbytes = size; + } + + dcbuf = vmemdup_user(buf, nbytes); + if (IS_ERR(dcbuf)) { + retval = PTR_ERR(dcbuf); + goto out; + } + + /* what downcall errors does Venus handle ? */ + error = coda_downcall(vcp, hdr.opcode, dcbuf, nbytes); + + kvfree(dcbuf); + if (error) { + pr_warn("%s: coda_downcall error: %d\n", + __func__, error); + retval = error; + goto out; + } + count = nbytes; + goto out; + } + + /* Look for the message on the processing queue. */ + mutex_lock(&vcp->vc_mutex); + list_for_each(lh, &vcp->vc_processing) { + tmp = list_entry(lh, struct upc_req , uc_chain); + if (tmp->uc_unique == hdr.unique) { + req = tmp; + list_del(&req->uc_chain); + break; + } + } + mutex_unlock(&vcp->vc_mutex); + + if (!req) { + pr_warn("%s: msg (%d, %d) not found\n", + __func__, hdr.opcode, hdr.unique); + retval = -ESRCH; + goto out; + } + + /* move data into response buffer. */ + if (req->uc_outSize < nbytes) { + pr_warn("%s: too much cnt: %d, cnt: %ld, opc: %d, uniq: %d.\n", + __func__, req->uc_outSize, (long)nbytes, + hdr.opcode, hdr.unique); + nbytes = req->uc_outSize; /* don't have more space! */ + } + if (copy_from_user(req->uc_data, buf, nbytes)) { + req->uc_flags |= CODA_REQ_ABORT; + wake_up(&req->uc_sleep); + retval = -EFAULT; + goto out; + } + + /* adjust outsize. is this useful ?? */ + req->uc_outSize = nbytes; + req->uc_flags |= CODA_REQ_WRITE; + count = nbytes; + + /* Convert filedescriptor into a file handle */ + if (req->uc_opcode == CODA_OPEN_BY_FD) { + struct coda_open_by_fd_out *outp = + (struct coda_open_by_fd_out *)req->uc_data; + if (!outp->oh.result) { + outp->fh = fget(outp->fd); + if (!outp->fh) + return -EBADF; + } + } + + wake_up(&req->uc_sleep); +out: + return(count ? count : retval); +} + +/* + * Read a message from the kernel to Venus + */ + +static ssize_t coda_psdev_read(struct file * file, char __user * buf, + size_t nbytes, loff_t *off) +{ + DECLARE_WAITQUEUE(wait, current); + struct venus_comm *vcp = (struct venus_comm *) file->private_data; + struct upc_req *req; + ssize_t retval = 0, count = 0; + + if (nbytes == 0) + return 0; + + mutex_lock(&vcp->vc_mutex); + + add_wait_queue(&vcp->vc_waitq, &wait); + set_current_state(TASK_INTERRUPTIBLE); + + while (list_empty(&vcp->vc_pending)) { + if (file->f_flags & O_NONBLOCK) { + retval = -EAGAIN; + break; + } + if (signal_pending(current)) { + retval = -ERESTARTSYS; + break; + } + mutex_unlock(&vcp->vc_mutex); + schedule(); + mutex_lock(&vcp->vc_mutex); + } + + set_current_state(TASK_RUNNING); + remove_wait_queue(&vcp->vc_waitq, &wait); + + if (retval) + goto out; + + req = list_entry(vcp->vc_pending.next, struct upc_req,uc_chain); + list_del(&req->uc_chain); + + /* Move the input args into userspace */ + count = req->uc_inSize; + if (nbytes < req->uc_inSize) { + pr_warn("%s: Venus read %ld bytes of %d in message\n", + __func__, (long)nbytes, req->uc_inSize); + count = nbytes; + } + + if (copy_to_user(buf, req->uc_data, count)) + retval = -EFAULT; + + /* If request was not a signal, enqueue and don't free */ + if (!(req->uc_flags & CODA_REQ_ASYNC)) { + req->uc_flags |= CODA_REQ_READ; + list_add_tail(&(req->uc_chain), &vcp->vc_processing); + goto out; + } + + kvfree(req->uc_data); + kfree(req); +out: + mutex_unlock(&vcp->vc_mutex); + return (count ? count : retval); +} + +static int coda_psdev_open(struct inode * inode, struct file * file) +{ + struct venus_comm *vcp; + int idx, err; + + if (task_active_pid_ns(current) != &init_pid_ns) + return -EINVAL; + + if (current_user_ns() != &init_user_ns) + return -EINVAL; + + idx = iminor(inode); + if (idx < 0 || idx >= MAX_CODADEVS) + return -ENODEV; + + err = -EBUSY; + vcp = &coda_comms[idx]; + mutex_lock(&vcp->vc_mutex); + + if (!vcp->vc_inuse) { + vcp->vc_inuse++; + + INIT_LIST_HEAD(&vcp->vc_pending); + INIT_LIST_HEAD(&vcp->vc_processing); + init_waitqueue_head(&vcp->vc_waitq); + vcp->vc_sb = NULL; + vcp->vc_seq = 0; + + file->private_data = vcp; + err = 0; + } + + mutex_unlock(&vcp->vc_mutex); + return err; +} + + +static int coda_psdev_release(struct inode * inode, struct file * file) +{ + struct venus_comm *vcp = (struct venus_comm *) file->private_data; + struct upc_req *req, *tmp; + + if (!vcp || !vcp->vc_inuse ) { + pr_warn("%s: Not open.\n", __func__); + return -1; + } + + mutex_lock(&vcp->vc_mutex); + + /* Wakeup clients so they can return. */ + list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) { + list_del(&req->uc_chain); + + /* Async requests need to be freed here */ + if (req->uc_flags & CODA_REQ_ASYNC) { + kvfree(req->uc_data); + kfree(req); + continue; + } + req->uc_flags |= CODA_REQ_ABORT; + wake_up(&req->uc_sleep); + } + + list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) { + list_del(&req->uc_chain); + + req->uc_flags |= CODA_REQ_ABORT; + wake_up(&req->uc_sleep); + } + + file->private_data = NULL; + vcp->vc_inuse--; + mutex_unlock(&vcp->vc_mutex); + return 0; +} + + +static const struct file_operations coda_psdev_fops = { + .owner = THIS_MODULE, + .read = coda_psdev_read, + .write = coda_psdev_write, + .poll = coda_psdev_poll, + .unlocked_ioctl = coda_psdev_ioctl, + .open = coda_psdev_open, + .release = coda_psdev_release, + .llseek = noop_llseek, +}; + +static int __init init_coda_psdev(void) +{ + int i, err = 0; + if (register_chrdev(CODA_PSDEV_MAJOR, "coda", &coda_psdev_fops)) { + pr_err("%s: unable to get major %d\n", + __func__, CODA_PSDEV_MAJOR); + return -EIO; + } + coda_psdev_class = class_create("coda"); + if (IS_ERR(coda_psdev_class)) { + err = PTR_ERR(coda_psdev_class); + goto out_chrdev; + } + for (i = 0; i < MAX_CODADEVS; i++) { + mutex_init(&(&coda_comms[i])->vc_mutex); + device_create(coda_psdev_class, NULL, + MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i); + } + coda_sysctl_init(); + goto out; + +out_chrdev: + unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); +out: + return err; +} + +MODULE_AUTHOR("Jan Harkes, Peter J. Braam"); +MODULE_DESCRIPTION("Coda Distributed File System VFS interface"); +MODULE_ALIAS_CHARDEV_MAJOR(CODA_PSDEV_MAJOR); +MODULE_LICENSE("GPL"); +MODULE_VERSION("7.2"); + +static int __init init_coda(void) +{ + int status; + int i; + + status = coda_init_inodecache(); + if (status) + goto out2; + status = init_coda_psdev(); + if ( status ) { + pr_warn("Problem (%d) in init_coda_psdev\n", status); + goto out1; + } + + status = register_filesystem(&coda_fs_type); + if (status) { + pr_warn("failed to register filesystem!\n"); + goto out; + } + return 0; +out: + for (i = 0; i < MAX_CODADEVS; i++) + device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i)); + class_destroy(coda_psdev_class); + unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); + coda_sysctl_clean(); +out1: + coda_destroy_inodecache(); +out2: + return status; +} + +static void __exit exit_coda(void) +{ + int err, i; + + err = unregister_filesystem(&coda_fs_type); + if (err != 0) + pr_warn("failed to unregister filesystem\n"); + for (i = 0; i < MAX_CODADEVS; i++) + device_destroy(coda_psdev_class, MKDEV(CODA_PSDEV_MAJOR, i)); + class_destroy(coda_psdev_class); + unregister_chrdev(CODA_PSDEV_MAJOR, "coda"); + coda_sysctl_clean(); + coda_destroy_inodecache(); +} + +module_init(init_coda); +module_exit(exit_coda); + -- cgit v1.2.3