diff options
Diffstat (limited to 'drivers/s390/char/monreader.c')
| -rw-r--r-- | drivers/s390/char/monreader.c | 662 |
1 files changed, 662 insertions, 0 deletions
diff --git a/drivers/s390/char/monreader.c b/drivers/s390/char/monreader.c new file mode 100644 index 000000000000..5fd3ad867386 --- /dev/null +++ b/drivers/s390/char/monreader.c @@ -0,0 +1,662 @@ +/* + * drivers/s390/char/monreader.c + * + * Character device driver for reading z/VM *MONITOR service records. + * + * Copyright (C) 2004 IBM Corporation, IBM Deutschland Entwicklung GmbH. + * + * Author: Gerald Schaefer <geraldsc@de.ibm.com> + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/miscdevice.h> +#include <linux/ctype.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <asm/uaccess.h> +#include <asm/ebcdic.h> +#include <asm/extmem.h> +#include <linux/poll.h> +#include "../net/iucv.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 +#define MON_SERVICE "*MONITOR" +#define MON_IN_USE 0x01 +#define MON_MSGLIM 255 + +static char mon_dcss_name[9] = "MONDCSS\0"; + +struct mon_msg { + u32 pos; + u32 mca_offset; + iucv_MessagePending local_eib; + char msglim_reached; + char replied_msglim; +}; + +struct mon_private { + u16 pathid; + iucv_handle_t iucv_handle; + struct mon_msg *msg_array[MON_MSGLIM]; + unsigned int write_index; + unsigned int read_index; + atomic_t msglim_count; + atomic_t read_ready; + atomic_t iucv_connected; + atomic_t iucv_severed; +}; + +static unsigned long mon_in_use = 0; + +static unsigned long mon_dcss_start; +static unsigned long mon_dcss_end; + +static DECLARE_WAIT_QUEUE_HEAD(mon_read_wait_queue); +static DECLARE_WAIT_QUEUE_HEAD(mon_conn_wait_queue); + +static u8 iucv_host[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; + +static u8 user_data_connect[16] = { + /* Version code, must be 0x01 for shared mode */ + 0x01, + /* what to collect */ + MON_COLLECT_SAMPLE | MON_COLLECT_EVENT, + /* DCSS name in EBCDIC, 8 bytes padded with blanks */ + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, +}; + +static u8 user_data_sever[16] = { + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, +}; + + +/****************************************************************************** + * helper functions * + *****************************************************************************/ +/* + * Create the 8 bytes EBCDIC DCSS segment name from + * an ASCII name, incl. padding + */ +static inline void +dcss_mkname(char *ascii_name, char *ebcdic_name) +{ + int i; + + for (i = 0; i < 8; i++) { + if (ascii_name[i] == '\0') + break; + ebcdic_name[i] = toupper(ascii_name[i]); + }; + for (; i < 8; i++) + ebcdic_name[i] = ' '; + ASCEBC(ebcdic_name, 8); +} + +/* + * print appropriate error message for segment_load()/segment_type() + * return code + */ +static void +mon_segment_warn(int rc, char* seg_name) +{ + switch (rc) { + case -ENOENT: + P_WARNING("cannot load/query segment %s, does not exist\n", + seg_name); + break; + case -ENOSYS: + P_WARNING("cannot load/query segment %s, not running on VM\n", + seg_name); + break; + case -EIO: + P_WARNING("cannot load/query segment %s, hardware error\n", + seg_name); + break; + case -ENOTSUPP: + P_WARNING("cannot load/query segment %s, is a multi-part " + "segment\n", seg_name); + break; + case -ENOSPC: + P_WARNING("cannot load/query segment %s, overlaps with " + "storage\n", seg_name); + break; + case -EBUSY: + P_WARNING("cannot load/query segment %s, overlaps with " + "already loaded dcss\n", seg_name); + break; + case -EPERM: + P_WARNING("cannot load/query segment %s, already loaded in " + "incompatible mode\n", seg_name); + break; + case -ENOMEM: + P_WARNING("cannot load/query segment %s, out of memory\n", + seg_name); + break; + case -ERANGE: + P_WARNING("cannot load/query segment %s, exceeds kernel " + "mapping range\n", seg_name); + break; + default: + P_WARNING("cannot load/query segment %s, return value %i\n", + seg_name, rc); + break; + } +} + +static inline unsigned long +mon_mca_start(struct mon_msg *monmsg) +{ + return monmsg->local_eib.ln1msg1.iprmmsg1_u32; +} + +static inline unsigned long +mon_mca_end(struct mon_msg *monmsg) +{ + return monmsg->local_eib.ln1msg2.ipbfln1f; +} + +static inline u8 +mon_mca_type(struct mon_msg *monmsg, u8 index) +{ + return *((u8 *) mon_mca_start(monmsg) + monmsg->mca_offset + index); +} + +static inline u32 +mon_mca_size(struct mon_msg *monmsg) +{ + return mon_mca_end(monmsg) - mon_mca_start(monmsg) + 1; +} + +static inline u32 +mon_rec_start(struct mon_msg *monmsg) +{ + return *((u32 *) (mon_mca_start(monmsg) + monmsg->mca_offset + 4)); +} + +static inline u32 +mon_rec_end(struct mon_msg *monmsg) +{ + return *((u32 *) (mon_mca_start(monmsg) + monmsg->mca_offset + 8)); +} + +static inline int +mon_check_mca(struct mon_msg *monmsg) +{ + if ((mon_rec_end(monmsg) <= mon_rec_start(monmsg)) || + (mon_rec_start(monmsg) < mon_dcss_start) || + (mon_rec_end(monmsg) > mon_dcss_end) || + (mon_mca_type(monmsg, 0) == 0) || + (mon_mca_size(monmsg) % 12 != 0) || + (mon_mca_end(monmsg) <= mon_mca_start(monmsg)) || + (mon_mca_end(monmsg) > mon_dcss_end) || + (mon_mca_start(monmsg) < mon_dcss_start) || + ((mon_mca_type(monmsg, 1) == 0) && (mon_mca_type(monmsg, 2) == 0))) + { + P_DEBUG("READ, IGNORED INVALID MCA\n\n"); + return -EINVAL; + } + return 0; +} + +static inline int +mon_send_reply(struct mon_msg *monmsg, struct mon_private *monpriv) +{ + u8 prmmsg[8]; + int rc; + + P_DEBUG("read, REPLY: pathid = 0x%04X, msgid = 0x%08X, trgcls = " + "0x%08X\n\n", + monmsg->local_eib.ippathid, monmsg->local_eib.ipmsgid, + monmsg->local_eib.iptrgcls); + rc = iucv_reply_prmmsg(monmsg->local_eib.ippathid, + monmsg->local_eib.ipmsgid, + monmsg->local_eib.iptrgcls, + 0, prmmsg); + atomic_dec(&monpriv->msglim_count); + if (likely(!monmsg->msglim_reached)) { + monmsg->pos = 0; + monmsg->mca_offset = 0; + monpriv->read_index = (monpriv->read_index + 1) % + MON_MSGLIM; + atomic_dec(&monpriv->read_ready); + } else + monmsg->replied_msglim = 1; + if (rc) { + P_ERROR("read, IUCV reply failed with rc = %i\n\n", rc); + return -EIO; + } + return 0; +} + +static inline struct mon_private * +mon_alloc_mem(void) +{ + int i,j; + struct mon_private *monpriv; + + monpriv = kmalloc(sizeof(struct mon_private), GFP_KERNEL); + if (!monpriv) { + P_ERROR("no memory for monpriv\n"); + return NULL; + } + memset(monpriv, 0, sizeof(struct mon_private)); + for (i = 0; i < MON_MSGLIM; i++) { + monpriv->msg_array[i] = kmalloc(sizeof(struct mon_msg), + GFP_KERNEL); + if (!monpriv->msg_array[i]) { + P_ERROR("open, no memory for msg_array\n"); + for (j = 0; j < i; j++) + kfree(monpriv->msg_array[j]); + return NULL; + } + memset(monpriv->msg_array[i], 0, sizeof(struct mon_msg)); + } + return monpriv; +} + +static inline void +mon_read_debug(struct mon_msg *monmsg, struct mon_private *monpriv) +{ +#ifdef MON_DEBUG + u8 msg_type[2], mca_type; + unsigned long records_len; + + records_len = mon_rec_end(monmsg) - mon_rec_start(monmsg) + 1; + + memcpy(msg_type, &monmsg->local_eib.iptrgcls, 2); + EBCASC(msg_type, 2); + mca_type = mon_mca_type(monmsg, 0); + EBCASC(&mca_type, 1); + + P_DEBUG("read, mon_read_index = %i, mon_write_index = %i\n", + monpriv->read_index, monpriv->write_index); + P_DEBUG("read, pathid = 0x%04X, msgid = 0x%08X, trgcls = 0x%08X\n", + monmsg->local_eib.ippathid, monmsg->local_eib.ipmsgid, + monmsg->local_eib.iptrgcls); + P_DEBUG("read, msg_type = '%c%c', mca_type = '%c' / 0x%X / 0x%X\n", + msg_type[0], msg_type[1], mca_type ? mca_type : 'X', + mon_mca_type(monmsg, 1), mon_mca_type(monmsg, 2)); + P_DEBUG("read, MCA: start = 0x%lX, end = 0x%lX\n", + mon_mca_start(monmsg), mon_mca_end(monmsg)); + P_DEBUG("read, REC: start = 0x%X, end = 0x%X, len = %lu\n\n", + mon_rec_start(monmsg), mon_rec_end(monmsg), records_len); + if (mon_mca_size(monmsg) > 12) + P_DEBUG("READ, MORE THAN ONE MCA\n\n"); +#endif +} + +static inline void +mon_next_mca(struct mon_msg *monmsg) +{ + if (likely((mon_mca_size(monmsg) - monmsg->mca_offset) == 12)) + return; + P_DEBUG("READ, NEXT MCA\n\n"); + monmsg->mca_offset += 12; + monmsg->pos = 0; +} + +static inline struct mon_msg * +mon_next_message(struct mon_private *monpriv) +{ + struct mon_msg *monmsg; + + if (!atomic_read(&monpriv->read_ready)) + return NULL; + monmsg = monpriv->msg_array[monpriv->read_index]; + if (unlikely(monmsg->replied_msglim)) { + monmsg->replied_msglim = 0; + monmsg->msglim_reached = 0; + monmsg->pos = 0; + monmsg->mca_offset = 0; + P_WARNING("read, message limit reached\n"); + monpriv->read_index = (monpriv->read_index + 1) % + MON_MSGLIM; + atomic_dec(&monpriv->read_ready); + return ERR_PTR(-EOVERFLOW); + } + return monmsg; +} + + +/****************************************************************************** + * IUCV handler * + *****************************************************************************/ +static void +mon_iucv_ConnectionComplete(iucv_ConnectionComplete *eib, void *pgm_data) +{ + struct mon_private *monpriv = (struct mon_private *) pgm_data; + + P_DEBUG("IUCV connection completed\n"); + P_DEBUG("IUCV ACCEPT (from *MONITOR): Version = 0x%02X, Event = " + "0x%02X, Sample = 0x%02X\n", + eib->ipuser[0], eib->ipuser[1], eib->ipuser[2]); + atomic_set(&monpriv->iucv_connected, 1); + wake_up(&mon_conn_wait_queue); +} + +static void +mon_iucv_ConnectionSevered(iucv_ConnectionSevered *eib, void *pgm_data) +{ + struct mon_private *monpriv = (struct mon_private *) pgm_data; + + P_ERROR("IUCV connection severed with rc = 0x%X\n", + (u8) eib->ipuser[0]); + atomic_set(&monpriv->iucv_severed, 1); + wake_up(&mon_conn_wait_queue); + wake_up_interruptible(&mon_read_wait_queue); +} + +static void +mon_iucv_MessagePending(iucv_MessagePending *eib, void *pgm_data) +{ + struct mon_private *monpriv = (struct mon_private *) pgm_data; + + P_DEBUG("IUCV message pending\n"); + memcpy(&monpriv->msg_array[monpriv->write_index]->local_eib, eib, + sizeof(iucv_MessagePending)); + if (atomic_inc_return(&monpriv->msglim_count) == MON_MSGLIM) { + P_WARNING("IUCV message pending, message limit (%i) reached\n", + MON_MSGLIM); + monpriv->msg_array[monpriv->write_index]->msglim_reached = 1; + } + monpriv->write_index = (monpriv->write_index + 1) % MON_MSGLIM; + atomic_inc(&monpriv->read_ready); + wake_up_interruptible(&mon_read_wait_queue); +} + +static iucv_interrupt_ops_t mon_iucvops = { + .ConnectionComplete = mon_iucv_ConnectionComplete, + .ConnectionSevered = mon_iucv_ConnectionSevered, + .MessagePending = mon_iucv_MessagePending, +}; + +/****************************************************************************** + * file operations * + *****************************************************************************/ +static int +mon_open(struct inode *inode, struct file *filp) +{ + int rc, i; + struct mon_private *monpriv; + + /* + * only one user allowed + */ + if (test_and_set_bit(MON_IN_USE, &mon_in_use)) + return -EBUSY; + + monpriv = mon_alloc_mem(); + if (!monpriv) + return -ENOMEM; + + /* + * Register with IUCV and connect to *MONITOR service + */ + monpriv->iucv_handle = iucv_register_program("my_monreader ", + MON_SERVICE, + NULL, + &mon_iucvops, + monpriv); + if (!monpriv->iucv_handle) { + P_ERROR("failed to register with iucv driver\n"); + rc = -EIO; + goto out_error; + } + P_INFO("open, registered with IUCV\n"); + + rc = iucv_connect(&monpriv->pathid, MON_MSGLIM, user_data_connect, + MON_SERVICE, iucv_host, IPRMDATA, NULL, NULL, + monpriv->iucv_handle, NULL); + if (rc) { + P_ERROR("iucv connection to *MONITOR failed with " + "IPUSER SEVER code = %i\n", rc); + rc = -EIO; + goto out_unregister; + } + /* + * Wait for connection confirmation + */ + wait_event(mon_conn_wait_queue, + atomic_read(&monpriv->iucv_connected) || + atomic_read(&monpriv->iucv_severed)); + if (atomic_read(&monpriv->iucv_severed)) { + atomic_set(&monpriv->iucv_severed, 0); + atomic_set(&monpriv->iucv_connected, 0); + rc = -EIO; + goto out_unregister; + } + P_INFO("open, established connection to *MONITOR service\n\n"); + filp->private_data = monpriv; + return nonseekable_open(inode, filp); + +out_unregister: + iucv_unregister_program(monpriv->iucv_handle); +out_error: + for (i = 0; i < MON_MSGLIM; i++) + kfree(monpriv->msg_array[i]); + kfree(monpriv); + clear_bit(MON_IN_USE, &mon_in_use); + return rc; +} + +static int +mon_close(struct inode *inode, struct file *filp) +{ + int rc, i; + struct mon_private *monpriv = filp->private_data; + + /* + * Close IUCV connection and unregister + */ + rc = iucv_sever(monpriv->pathid, user_data_sever); + if (rc) + P_ERROR("close, iucv_sever failed with rc = %i\n", rc); + else + P_INFO("close, terminated connection to *MONITOR service\n"); + + rc = iucv_unregister_program(monpriv->iucv_handle); + if (rc) + P_ERROR("close, iucv_unregister failed with rc = %i\n", rc); + else + P_INFO("close, unregistered with IUCV\n"); + + 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; + + for (i = 0; i < MON_MSGLIM; i++) + kfree(monpriv->msg_array[i]); + kfree(monpriv); + clear_bit(MON_IN_USE, &mon_in_use); + return 0; +} + +static ssize_t +mon_read(struct file *filp, char __user *data, size_t count, loff_t *ppos) +{ + struct mon_private *monpriv = filp->private_data; + struct mon_msg *monmsg; + int ret; + u32 mce_start; + + monmsg = mon_next_message(monpriv); + if (IS_ERR(monmsg)) + return PTR_ERR(monmsg); + + if (!monmsg) { + if (filp->f_flags & O_NONBLOCK) + return -EAGAIN; + ret = wait_event_interruptible(mon_read_wait_queue, + atomic_read(&monpriv->read_ready) || + atomic_read(&monpriv->iucv_severed)); + if (ret) + return ret; + if (unlikely(atomic_read(&monpriv->iucv_severed))) + return -EIO; + monmsg = monpriv->msg_array[monpriv->read_index]; + } + + if (!monmsg->pos) { + monmsg->pos = mon_mca_start(monmsg) + monmsg->mca_offset; + mon_read_debug(monmsg, monpriv); + } + if (mon_check_mca(monmsg)) + goto reply; + + /* read monitor control element (12 bytes) first */ + mce_start = mon_mca_start(monmsg) + monmsg->mca_offset; + if ((monmsg->pos >= mce_start) && (monmsg->pos < mce_start + 12)) { + count = min(count, (size_t) mce_start + 12 - monmsg->pos); + ret = copy_to_user(data, (void *) (unsigned long) monmsg->pos, + count); + if (ret) + return -EFAULT; + monmsg->pos += count; + if (monmsg->pos == mce_start + 12) + monmsg->pos = mon_rec_start(monmsg); + goto out_copy; + } + + /* read records */ + if (monmsg->pos <= mon_rec_end(monmsg)) { + count = min(count, (size_t) mon_rec_end(monmsg) - monmsg->pos + + 1); + ret = copy_to_user(data, (void *) (unsigned long) monmsg->pos, + count); + if (ret) + return -EFAULT; + monmsg->pos += count; + if (monmsg->pos > mon_rec_end(monmsg)) + mon_next_mca(monmsg); + goto out_copy; + } +reply: + ret = mon_send_reply(monmsg, monpriv); + return ret; + +out_copy: + *ppos += count; + return count; +} + +static unsigned int +mon_poll(struct file *filp, struct poll_table_struct *p) +{ + struct mon_private *monpriv = filp->private_data; + + poll_wait(filp, &mon_read_wait_queue, p); + if (unlikely(atomic_read(&monpriv->iucv_severed))) + return POLLERR; + if (atomic_read(&monpriv->read_ready)) + return POLLIN | POLLRDNORM; + return 0; +} + +static struct file_operations mon_fops = { + .owner = THIS_MODULE, + .open = &mon_open, + .release = &mon_close, + .read = &mon_read, + .poll = &mon_poll, +}; + +static struct miscdevice mon_dev = { + .name = "monreader", + .devfs_name = "monreader", + .fops = &mon_fops, + .minor = MISC_DYNAMIC_MINOR, +}; + +/****************************************************************************** + * module init/exit * + *****************************************************************************/ +static int __init +mon_init(void) +{ + int rc; + + if (!MACHINE_IS_VM) { + P_ERROR("not running under z/VM, driver not loaded\n"); + return -ENODEV; + } + + rc = segment_type(mon_dcss_name); + if (rc < 0) { + mon_segment_warn(rc, mon_dcss_name); + return rc; + } + if (rc != SEG_TYPE_SC) { + P_ERROR("segment %s has unsupported type, should be SC\n", + mon_dcss_name); + return -EINVAL; + } + + rc = segment_load(mon_dcss_name, SEGMENT_SHARED, + &mon_dcss_start, &mon_dcss_end); + if (rc < 0) { + mon_segment_warn(rc, mon_dcss_name); + return -EINVAL; + } + dcss_mkname(mon_dcss_name, &user_data_connect[8]); + + rc = misc_register(&mon_dev); + if (rc < 0 ) { + P_ERROR("misc_register failed, rc = %i\n", rc); + goto out; + } + P_INFO("Loaded segment %s from %p to %p, size = %lu Byte\n", + mon_dcss_name, (void *) mon_dcss_start, (void *) mon_dcss_end, + mon_dcss_end - mon_dcss_start + 1); + return 0; + +out: + segment_unload(mon_dcss_name); + return rc; +} + +static void __exit +mon_exit(void) +{ + segment_unload(mon_dcss_name); + WARN_ON(misc_deregister(&mon_dev) != 0); + return; +} + + +module_init(mon_init); +module_exit(mon_exit); + +module_param_string(mondcss, mon_dcss_name, 9, 0444); +MODULE_PARM_DESC(mondcss, "Name of DCSS segment to be used for *MONITOR " + "service, max. 8 chars. Default is MONDCSS"); + +MODULE_AUTHOR("Gerald Schaefer <geraldsc@de.ibm.com>"); +MODULE_DESCRIPTION("Character device driver for reading z/VM " + "monitor service records."); +MODULE_LICENSE("GPL"); |