--- /dev/null
+/*
+ * IBM ASM Service Processor Device Driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2004
+ *
+ * Author: Max Asböck <amax@us.ibm.com>
+ *
+ */
+
+/*
+ * Parts of this code are based on an article by Jonathan Corbet
+ * that appeared in Linux Weekly News.
+ */
+
+
+/*
+ * The IBMASM file virtual filesystem. It creates the following hierarchy
+ * dynamically when mounted from user space:
+ *
+ * /ibmasm
+ * |-- 0
+ * | |-- command
+ * | |-- event
+ * | |-- reverse_heartbeat
+ * | `-- remote_video
+ * | |-- depth
+ * | |-- height
+ * | `-- width
+ * .
+ * .
+ * .
+ * `-- n
+ * |-- command
+ * |-- event
+ * |-- reverse_heartbeat
+ * `-- remote_video
+ * |-- depth
+ * |-- height
+ * `-- width
+ *
+ * For each service processor the following files are created:
+ *
+ * command: execute dot commands
+ * write: execute a dot command on the service processor
+ * read: return the result of a previously executed dot command
+ *
+ * events: listen for service processor events
+ * read: sleep (interruptible) until an event occurs
+ * write: wakeup sleeping event listener
+ *
+ * reverse_heartbeat: send a heartbeat to the service processor
+ * read: sleep (interruptible) until the reverse heartbeat fails
+ * write: wakeup sleeping heartbeat listener
+ *
+ * remote_video/width
+ * remote_video/height
+ * remote_video/width: control remote display settings
+ * write: set value
+ * read: read value
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include "ibmasm.h"
+#include "remote.h"
+#include "dot_command.h"
+
+#define IBMASMFS_MAGIC 0x66726f67
+
+static LIST_HEAD(service_processors);
+
+static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode);
+static void ibmasmfs_create_files (struct super_block *sb);
+static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent);
+
+
+static struct dentry *ibmasmfs_mount(struct file_system_type *fst,
+ int flags, const char *name, void *data)
+{
+ return mount_single(fst, flags, data, ibmasmfs_fill_super);
+}
+
+static const struct super_operations ibmasmfs_s_ops = {
+ .statfs = simple_statfs,
+ .drop_inode = generic_delete_inode,
+};
+
+static const struct file_operations *ibmasmfs_dir_ops = &simple_dir_operations;
+
+static struct file_system_type ibmasmfs_type = {
+ .owner = THIS_MODULE,
+ .name = "ibmasmfs",
+ .mount = ibmasmfs_mount,
+ .kill_sb = kill_litter_super,
+};
+MODULE_ALIAS_FS("ibmasmfs");
+
+static int ibmasmfs_fill_super (struct super_block *sb, void *data, int silent)
+{
+ struct inode *root;
+
+ sb->s_blocksize = PAGE_CACHE_SIZE;
+ sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_magic = IBMASMFS_MAGIC;
+ sb->s_op = &ibmasmfs_s_ops;
+ sb->s_time_gran = 1;
+
+ root = ibmasmfs_make_inode (sb, S_IFDIR | 0500);
+ if (!root)
+ return -ENOMEM;
+
+ root->i_op = &simple_dir_inode_operations;
+ root->i_fop = ibmasmfs_dir_ops;
+
+ sb->s_root = d_make_root(root);
+ if (!sb->s_root)
+ return -ENOMEM;
+
+ ibmasmfs_create_files(sb);
+ return 0;
+}
+
+static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
+{
+ struct inode *ret = new_inode(sb);
+
+ if (ret) {
+ ret->i_ino = get_next_ino();
+ ret->i_mode = mode;
+ ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
+ }
+ return ret;
+}
+
+static struct dentry *ibmasmfs_create_file(struct dentry *parent,
+ const char *name,
+ const struct file_operations *fops,
+ void *data,
+ int mode)
+{
+ struct dentry *dentry;
+ struct inode *inode;
+
+ dentry = d_alloc_name(parent, name);
+ if (!dentry)
+ return NULL;
+
+ inode = ibmasmfs_make_inode(parent->d_sb, S_IFREG | mode);
+ if (!inode) {
+ dput(dentry);
+ return NULL;
+ }
+
+ inode->i_fop = fops;
+ inode->i_private = data;
+
+ d_add(dentry, inode);
+ return dentry;
+}
+
+static struct dentry *ibmasmfs_create_dir(struct dentry *parent,
+ const char *name)
+{
+ struct dentry *dentry;
+ struct inode *inode;
+
+ dentry = d_alloc_name(parent, name);
+ if (!dentry)
+ return NULL;
+
+ inode = ibmasmfs_make_inode(parent->d_sb, S_IFDIR | 0500);
+ if (!inode) {
+ dput(dentry);
+ return NULL;
+ }
+
+ inode->i_op = &simple_dir_inode_operations;
+ inode->i_fop = ibmasmfs_dir_ops;
+
+ d_add(dentry, inode);
+ return dentry;
+}
+
+int ibmasmfs_register(void)
+{
+ return register_filesystem(&ibmasmfs_type);
+}
+
+void ibmasmfs_unregister(void)
+{
+ unregister_filesystem(&ibmasmfs_type);
+}
+
+void ibmasmfs_add_sp(struct service_processor *sp)
+{
+ list_add(&sp->node, &service_processors);
+}
+
+/* struct to save state between command file operations */
+struct ibmasmfs_command_data {
+ struct service_processor *sp;
+ struct command *command;
+};
+
+/* struct to save state between event file operations */
+struct ibmasmfs_event_data {
+ struct service_processor *sp;
+ struct event_reader reader;
+ int active;
+};
+
+/* struct to save state between reverse heartbeat file operations */
+struct ibmasmfs_heartbeat_data {
+ struct service_processor *sp;
+ struct reverse_heartbeat heartbeat;
+ int active;
+};
+
+static int command_file_open(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_command_data *command_data;
+
+ if (!inode->i_private)
+ return -ENODEV;
+
+ command_data = kmalloc(sizeof(struct ibmasmfs_command_data), GFP_KERNEL);
+ if (!command_data)
+ return -ENOMEM;
+
+ command_data->command = NULL;
+ command_data->sp = inode->i_private;
+ file->private_data = command_data;
+ return 0;
+}
+
+static int command_file_close(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_command_data *command_data = file->private_data;
+
+ if (command_data->command)
+ command_put(command_data->command);
+
+ kfree(command_data);
+ return 0;
+}
+
+static ssize_t command_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_command_data *command_data = file->private_data;
+ struct command *cmd;
+ int len;
+ unsigned long flags;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ spin_lock_irqsave(&command_data->sp->lock, flags);
+ cmd = command_data->command;
+ if (cmd == NULL) {
+ spin_unlock_irqrestore(&command_data->sp->lock, flags);
+ return 0;
+ }
+ command_data->command = NULL;
+ spin_unlock_irqrestore(&command_data->sp->lock, flags);
+
+ if (cmd->status != IBMASM_CMD_COMPLETE) {
+ command_put(cmd);
+ return -EIO;
+ }
+ len = min(count, cmd->buffer_size);
+ if (copy_to_user(buf, cmd->buffer, len)) {
+ command_put(cmd);
+ return -EFAULT;
+ }
+ command_put(cmd);
+
+ return len;
+}
+
+static ssize_t command_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_command_data *command_data = file->private_data;
+ struct command *cmd;
+ unsigned long flags;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > IBMASM_CMD_MAX_BUFFER_SIZE)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ /* commands are executed sequentially, only one command at a time */
+ if (command_data->command)
+ return -EAGAIN;
+
+ cmd = ibmasm_new_command(command_data->sp, count);
+ if (!cmd)
+ return -ENOMEM;
+
+ if (copy_from_user(cmd->buffer, ubuff, count)) {
+ command_put(cmd);
+ return -EFAULT;
+ }
+
+ spin_lock_irqsave(&command_data->sp->lock, flags);
+ if (command_data->command) {
+ spin_unlock_irqrestore(&command_data->sp->lock, flags);
+ command_put(cmd);
+ return -EAGAIN;
+ }
+ command_data->command = cmd;
+ spin_unlock_irqrestore(&command_data->sp->lock, flags);
+
+ ibmasm_exec_command(command_data->sp, cmd);
+ ibmasm_wait_for_response(cmd, get_dot_command_timeout(cmd->buffer));
+
+ return count;
+}
+
+static int event_file_open(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_event_data *event_data;
+ struct service_processor *sp;
+
+ if (!inode->i_private)
+ return -ENODEV;
+
+ sp = inode->i_private;
+
+ event_data = kmalloc(sizeof(struct ibmasmfs_event_data), GFP_KERNEL);
+ if (!event_data)
+ return -ENOMEM;
+
+ ibmasm_event_reader_register(sp, &event_data->reader);
+
+ event_data->sp = sp;
+ event_data->active = 0;
+ file->private_data = event_data;
+ return 0;
+}
+
+static int event_file_close(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_event_data *event_data = file->private_data;
+
+ ibmasm_event_reader_unregister(event_data->sp, &event_data->reader);
+ kfree(event_data);
+ return 0;
+}
+
+static ssize_t event_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_event_data *event_data = file->private_data;
+ struct event_reader *reader = &event_data->reader;
+ struct service_processor *sp = event_data->sp;
+ int ret;
+ unsigned long flags;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > IBMASM_EVENT_MAX_SIZE)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ spin_lock_irqsave(&sp->lock, flags);
+ if (event_data->active) {
+ spin_unlock_irqrestore(&sp->lock, flags);
+ return -EBUSY;
+ }
+ event_data->active = 1;
+ spin_unlock_irqrestore(&sp->lock, flags);
+
+ ret = ibmasm_get_next_event(sp, reader);
+ if (ret <= 0)
+ goto out;
+
+ if (count < reader->data_size) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (copy_to_user(buf, reader->data, reader->data_size)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ ret = reader->data_size;
+
+out:
+ event_data->active = 0;
+ return ret;
+}
+
+static ssize_t event_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_event_data *event_data = file->private_data;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count != 1)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ ibmasm_cancel_next_event(&event_data->reader);
+ return 0;
+}
+
+static int r_heartbeat_file_open(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_heartbeat_data *rhbeat;
+
+ if (!inode->i_private)
+ return -ENODEV;
+
+ rhbeat = kmalloc(sizeof(struct ibmasmfs_heartbeat_data), GFP_KERNEL);
+ if (!rhbeat)
+ return -ENOMEM;
+
+ rhbeat->sp = inode->i_private;
+ rhbeat->active = 0;
+ ibmasm_init_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
+ file->private_data = rhbeat;
+ return 0;
+}
+
+static int r_heartbeat_file_close(struct inode *inode, struct file *file)
+{
+ struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
+
+ kfree(rhbeat);
+ return 0;
+}
+
+static ssize_t r_heartbeat_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
+ unsigned long flags;
+ int result;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > 1024)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ /* allow only one reverse heartbeat per process */
+ spin_lock_irqsave(&rhbeat->sp->lock, flags);
+ if (rhbeat->active) {
+ spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
+ return -EBUSY;
+ }
+ rhbeat->active = 1;
+ spin_unlock_irqrestore(&rhbeat->sp->lock, flags);
+
+ result = ibmasm_start_reverse_heartbeat(rhbeat->sp, &rhbeat->heartbeat);
+ rhbeat->active = 0;
+
+ return result;
+}
+
+static ssize_t r_heartbeat_file_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
+{
+ struct ibmasmfs_heartbeat_data *rhbeat = file->private_data;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count != 1)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ if (rhbeat->active)
+ ibmasm_stop_reverse_heartbeat(&rhbeat->heartbeat);
+
+ return 1;
+}
+
+static int remote_settings_file_close(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+static ssize_t remote_settings_file_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
+{
+ void __iomem *address = (void __iomem *)file->private_data;
+ unsigned char *page;
+ int retval;
+ int len = 0;
+ unsigned int value;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > 1024)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ page = (unsigned char *)__get_free_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ value = readl(address);
+ len = sprintf(page, "%d\n", value);
+
+ if (copy_to_user(buf, page, len)) {
+ retval = -EFAULT;
+ goto exit;
+ }
+ *offset += len;
+ retval = len;
+
+exit:
+ free_page((unsigned long)page);
+ return retval;
+}
+
+static ssize_t remote_settings_file_write(struct file *file, const char __user *ubuff, size_t count, loff_t *offset)
+{
+ void __iomem *address = (void __iomem *)file->private_data;
+ char *buff;
+ unsigned int value;
+
+ if (*offset < 0)
+ return -EINVAL;
+ if (count == 0 || count > 1024)
+ return 0;
+ if (*offset != 0)
+ return 0;
+
+ buff = kzalloc (count + 1, GFP_KERNEL);
+ if (!buff)
+ return -ENOMEM;
+
+
+ if (copy_from_user(buff, ubuff, count)) {
+ kfree(buff);
+ return -EFAULT;
+ }
+
+ value = simple_strtoul(buff, NULL, 10);
+ writel(value, address);
+ kfree(buff);
+
+ return count;
+}
+
+static const struct file_operations command_fops = {
+ .open = command_file_open,
+ .release = command_file_close,
+ .read = command_file_read,
+ .write = command_file_write,
+ .llseek = generic_file_llseek,
+};
+
+static const struct file_operations event_fops = {
+ .open = event_file_open,
+ .release = event_file_close,
+ .read = event_file_read,
+ .write = event_file_write,
+ .llseek = generic_file_llseek,
+};
+
+static const struct file_operations r_heartbeat_fops = {
+ .open = r_heartbeat_file_open,
+ .release = r_heartbeat_file_close,
+ .read = r_heartbeat_file_read,
+ .write = r_heartbeat_file_write,
+ .llseek = generic_file_llseek,
+};
+
+static const struct file_operations remote_settings_fops = {
+ .open = simple_open,
+ .release = remote_settings_file_close,
+ .read = remote_settings_file_read,
+ .write = remote_settings_file_write,
+ .llseek = generic_file_llseek,
+};
+
+
+static void ibmasmfs_create_files (struct super_block *sb)
+{
+ struct list_head *entry;
+ struct service_processor *sp;
+
+ list_for_each(entry, &service_processors) {
+ struct dentry *dir;
+ struct dentry *remote_dir;
+ sp = list_entry(entry, struct service_processor, node);
+ dir = ibmasmfs_create_dir(sb->s_root, sp->dirname);
+ if (!dir)
+ continue;
+
+ ibmasmfs_create_file(dir, "command", &command_fops, sp, S_IRUSR|S_IWUSR);
+ ibmasmfs_create_file(dir, "event", &event_fops, sp, S_IRUSR|S_IWUSR);
+ ibmasmfs_create_file(dir, "reverse_heartbeat", &r_heartbeat_fops, sp, S_IRUSR|S_IWUSR);
+
+ remote_dir = ibmasmfs_create_dir(dir, "remote_video");
+ if (!remote_dir)
+ continue;
+
+ ibmasmfs_create_file(remote_dir, "width", &remote_settings_fops, (void *)display_width(sp), S_IRUSR|S_IWUSR);
+ ibmasmfs_create_file(remote_dir, "height", &remote_settings_fops, (void *)display_height(sp), S_IRUSR|S_IWUSR);
+ ibmasmfs_create_file(remote_dir, "depth", &remote_settings_fops, (void *)display_depth(sp), S_IRUSR|S_IWUSR);
+ }
+}
Code Review / kvmfornfv.git / blobdiff