diff options
Diffstat (limited to 'drivers/s390/char/monreader.c')
| -rw-r--r-- | drivers/s390/char/monreader.c | 196 |
1 files changed, 155 insertions, 41 deletions
diff --git a/drivers/s390/char/monreader.c b/drivers/s390/char/monreader.c index 35fd8dfcaaa..0da3ae3cd63 100644 --- a/drivers/s390/char/monreader.c +++ b/drivers/s390/char/monreader.c @@ -1,16 +1,17 @@ /* - * drivers/s390/char/monreader.c - * * Character device driver for reading z/VM *MONITOR service records. * - * Copyright IBM Corp. 2004, 2008 - * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com> + * Copyright IBM Corp. 2004, 2009 + * + * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com> */ +#define KMSG_COMPONENT "monreader" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/init.h> -#include <linux/smp_lock.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/kernel.h> @@ -19,24 +20,13 @@ #include <linux/spinlock.h> #include <linux/interrupt.h> #include <linux/poll.h> +#include <linux/device.h> +#include <linux/slab.h> #include <net/iucv/iucv.h> #include <asm/uaccess.h> #include <asm/ebcdic.h> #include <asm/extmem.h> -//#define MON_DEBUG /* Debug messages on/off */ - -#define MON_NAME "monreader" - -#define P_INFO(x...) printk(KERN_INFO MON_NAME " info: " x) -#define P_ERROR(x...) printk(KERN_ERR MON_NAME " error: " x) -#define P_WARNING(x...) printk(KERN_WARNING MON_NAME " warning: " x) - -#ifdef MON_DEBUG -#define P_DEBUG(x...) printk(KERN_DEBUG MON_NAME " debug: " x) -#else -#define P_DEBUG(x...) do {} while (0) -#endif #define MON_COLLECT_SAMPLE 0x80 #define MON_COLLECT_EVENT 0x40 @@ -88,6 +78,7 @@ static u8 user_data_sever[16] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, }; +static struct device *monreader_device; /****************************************************************************** * helper functions * @@ -172,7 +163,7 @@ static int mon_send_reply(struct mon_msg *monmsg, } else monmsg->replied_msglim = 1; if (rc) { - P_ERROR("read, IUCV reply failed with rc = %i\n\n", rc); + pr_err("Reading monitor data failed with rc=%i\n", rc); return -EIO; } return 0; @@ -183,8 +174,7 @@ static void mon_free_mem(struct mon_private *monpriv) int i; for (i = 0; i < MON_MSGLIM; i++) - if (monpriv->msg_array[i]) - kfree(monpriv->msg_array[i]); + kfree(monpriv->msg_array[i]); kfree(monpriv); } @@ -251,7 +241,8 @@ static void mon_iucv_path_severed(struct iucv_path *path, u8 ipuser[16]) { struct mon_private *monpriv = path->private; - P_ERROR("IUCV connection severed with rc = 0x%X\n", ipuser[0]); + pr_err("z/VM *MONITOR system service disconnected with rc=%i\n", + ipuser[0]); iucv_path_sever(path, NULL); atomic_set(&monpriv->iucv_severed, 1); wake_up(&mon_conn_wait_queue); @@ -266,8 +257,7 @@ static void mon_iucv_message_pending(struct iucv_path *path, memcpy(&monpriv->msg_array[monpriv->write_index]->msg, msg, sizeof(*msg)); if (atomic_inc_return(&monpriv->msglim_count) == MON_MSGLIM) { - P_WARNING("IUCV message pending, message limit (%i) reached\n", - MON_MSGLIM); + pr_warning("The read queue for monitor data is full\n"); monpriv->msg_array[monpriv->write_index]->msglim_reached = 1; } monpriv->write_index = (monpriv->write_index + 1) % MON_MSGLIM; @@ -292,7 +282,6 @@ static int mon_open(struct inode *inode, struct file *filp) /* * only one user allowed */ - lock_kernel(); rc = -EBUSY; if (test_and_set_bit(MON_IN_USE, &mon_in_use)) goto out; @@ -311,8 +300,8 @@ static int mon_open(struct inode *inode, struct file *filp) rc = iucv_path_connect(monpriv->path, &monreader_iucv_handler, MON_SERVICE, NULL, user_data_connect, monpriv); if (rc) { - P_ERROR("iucv connection to *MONITOR failed with " - "IPUSER SEVER code = %i\n", rc); + pr_err("Connecting to the z/VM *MONITOR system service " + "failed with rc=%i\n", rc); rc = -EIO; goto out_path; } @@ -329,17 +318,16 @@ static int mon_open(struct inode *inode, struct file *filp) goto out_path; } filp->private_data = monpriv; - unlock_kernel(); + dev_set_drvdata(monreader_device, monpriv); return nonseekable_open(inode, filp); out_path: - kfree(monpriv->path); + iucv_path_free(monpriv->path); out_priv: mon_free_mem(monpriv); out_use: clear_bit(MON_IN_USE, &mon_in_use); out: - unlock_kernel(); return rc; } @@ -351,9 +339,13 @@ static int mon_close(struct inode *inode, struct file *filp) /* * Close IUCV connection and unregister */ - rc = iucv_path_sever(monpriv->path, user_data_sever); - if (rc) - P_ERROR("close, iucv_sever failed with rc = %i\n", rc); + if (monpriv->path) { + rc = iucv_path_sever(monpriv->path, user_data_sever); + if (rc) + pr_warning("Disconnecting the z/VM *MONITOR system " + "service failed with rc=%i\n", rc); + iucv_path_free(monpriv->path); + } atomic_set(&monpriv->iucv_severed, 0); atomic_set(&monpriv->iucv_connected, 0); @@ -361,6 +353,7 @@ static int mon_close(struct inode *inode, struct file *filp) atomic_set(&monpriv->msglim_count, 0); monpriv->write_index = 0; monpriv->read_index = 0; + dev_set_drvdata(monreader_device, NULL); for (i = 0; i < MON_MSGLIM; i++) kfree(monpriv->msg_array[i]); @@ -453,6 +446,7 @@ static const struct file_operations mon_fops = { .release = &mon_close, .read = &mon_read, .poll = &mon_poll, + .llseek = noop_llseek, }; static struct miscdevice mon_dev = { @@ -461,6 +455,94 @@ static struct miscdevice mon_dev = { .minor = MISC_DYNAMIC_MINOR, }; + +/****************************************************************************** + * suspend / resume * + *****************************************************************************/ +static int monreader_freeze(struct device *dev) +{ + struct mon_private *monpriv = dev_get_drvdata(dev); + int rc; + + if (!monpriv) + return 0; + if (monpriv->path) { + rc = iucv_path_sever(monpriv->path, user_data_sever); + if (rc) + pr_warning("Disconnecting the z/VM *MONITOR system " + "service failed with rc=%i\n", rc); + iucv_path_free(monpriv->path); + } + atomic_set(&monpriv->iucv_severed, 0); + atomic_set(&monpriv->iucv_connected, 0); + atomic_set(&monpriv->read_ready, 0); + atomic_set(&monpriv->msglim_count, 0); + monpriv->write_index = 0; + monpriv->read_index = 0; + monpriv->path = NULL; + return 0; +} + +static int monreader_thaw(struct device *dev) +{ + struct mon_private *monpriv = dev_get_drvdata(dev); + int rc; + + if (!monpriv) + return 0; + rc = -ENOMEM; + monpriv->path = iucv_path_alloc(MON_MSGLIM, IUCV_IPRMDATA, GFP_KERNEL); + if (!monpriv->path) + goto out; + rc = iucv_path_connect(monpriv->path, &monreader_iucv_handler, + MON_SERVICE, NULL, user_data_connect, monpriv); + if (rc) { + pr_err("Connecting to the z/VM *MONITOR system service " + "failed with rc=%i\n", rc); + goto out_path; + } + wait_event(mon_conn_wait_queue, + atomic_read(&monpriv->iucv_connected) || + atomic_read(&monpriv->iucv_severed)); + if (atomic_read(&monpriv->iucv_severed)) + goto out_path; + return 0; +out_path: + rc = -EIO; + iucv_path_free(monpriv->path); + monpriv->path = NULL; +out: + atomic_set(&monpriv->iucv_severed, 1); + return rc; +} + +static int monreader_restore(struct device *dev) +{ + int rc; + + segment_unload(mon_dcss_name); + rc = segment_load(mon_dcss_name, SEGMENT_SHARED, + &mon_dcss_start, &mon_dcss_end); + if (rc < 0) { + segment_warning(rc, mon_dcss_name); + panic("fatal monreader resume error: no monitor dcss\n"); + } + return monreader_thaw(dev); +} + +static const struct dev_pm_ops monreader_pm_ops = { + .freeze = monreader_freeze, + .thaw = monreader_thaw, + .restore = monreader_restore, +}; + +static struct device_driver monreader_driver = { + .name = "monreader", + .bus = &iucv_bus, + .pm = &monreader_pm_ops, +}; + + /****************************************************************************** * module init/exit * *****************************************************************************/ @@ -469,7 +551,8 @@ static int __init mon_init(void) int rc; if (!MACHINE_IS_VM) { - P_ERROR("not running under z/VM, driver not loaded\n"); + pr_err("The z/VM *MONITOR record device driver cannot be " + "loaded without z/VM\n"); return -ENODEV; } @@ -478,20 +561,41 @@ static int __init mon_init(void) */ rc = iucv_register(&monreader_iucv_handler, 1); if (rc) { - P_ERROR("failed to register with iucv driver\n"); + pr_err("The z/VM *MONITOR record device driver failed to " + "register with IUCV\n"); return rc; } + rc = driver_register(&monreader_driver); + if (rc) + goto out_iucv; + monreader_device = kzalloc(sizeof(struct device), GFP_KERNEL); + if (!monreader_device) { + rc = -ENOMEM; + goto out_driver; + } + + dev_set_name(monreader_device, "monreader-dev"); + monreader_device->bus = &iucv_bus; + monreader_device->parent = iucv_root; + monreader_device->driver = &monreader_driver; + monreader_device->release = (void (*)(struct device *))kfree; + rc = device_register(monreader_device); + if (rc) { + put_device(monreader_device); + goto out_driver; + } + rc = segment_type(mon_dcss_name); if (rc < 0) { segment_warning(rc, mon_dcss_name); - goto out_iucv; + goto out_device; } if (rc != SEG_TYPE_SC) { - P_ERROR("segment %s has unsupported type, should be SC\n", - mon_dcss_name); + pr_err("The specified *MONITOR DCSS %s does not have the " + "required type SC\n", mon_dcss_name); rc = -EINVAL; - goto out_iucv; + goto out_device; } rc = segment_load(mon_dcss_name, SEGMENT_SHARED, @@ -499,10 +603,14 @@ static int __init mon_init(void) if (rc < 0) { segment_warning(rc, mon_dcss_name); rc = -EINVAL; - goto out_iucv; + goto out_device; } dcss_mkname(mon_dcss_name, &user_data_connect[8]); + /* + * misc_register() has to be the last action in module_init(), because + * file operations will be available right after this. + */ rc = misc_register(&mon_dev); if (rc < 0 ) goto out; @@ -510,6 +618,10 @@ static int __init mon_init(void) out: segment_unload(mon_dcss_name); +out_device: + device_unregister(monreader_device); +out_driver: + driver_unregister(&monreader_driver); out_iucv: iucv_unregister(&monreader_iucv_handler, 1); return rc; @@ -518,7 +630,9 @@ out_iucv: static void __exit mon_exit(void) { segment_unload(mon_dcss_name); - WARN_ON(misc_deregister(&mon_dev) != 0); + misc_deregister(&mon_dev); + device_unregister(monreader_device); + driver_unregister(&monreader_driver); iucv_unregister(&monreader_iucv_handler, 1); return; } |