diff options
Diffstat (limited to 'drivers/s390/char/sclp_async.c')
| -rw-r--r-- | drivers/s390/char/sclp_async.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/drivers/s390/char/sclp_async.c b/drivers/s390/char/sclp_async.c new file mode 100644 index 000000000000..daaec185ed36 --- /dev/null +++ b/drivers/s390/char/sclp_async.c @@ -0,0 +1,224 @@ +/* + * Enable Asynchronous Notification via SCLP. + * + * Copyright IBM Corp. 2009 + * Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com> + * + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/stat.h> +#include <linux/string.h> +#include <linux/ctype.h> +#include <linux/kmod.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/proc_fs.h> +#include <linux/sysctl.h> +#include <linux/utsname.h> +#include "sclp.h" + +static int callhome_enabled; +static struct sclp_req *request; +static struct sclp_async_sccb *sccb; +static int sclp_async_send_wait(char *message); +static struct ctl_table_header *callhome_sysctl_header; +static DEFINE_SPINLOCK(sclp_async_lock); +static char nodename[64]; +#define SCLP_NORMAL_WRITE 0x00 + +struct async_evbuf { + struct evbuf_header header; + u64 reserved; + u8 rflags; + u8 empty; + u8 rtype; + u8 otype; + char comp_id[12]; + char data[3000]; /* there is still some space left */ +} __attribute__((packed)); + +struct sclp_async_sccb { + struct sccb_header header; + struct async_evbuf evbuf; +} __attribute__((packed)); + +static struct sclp_register sclp_async_register = { + .send_mask = EVTYP_ASYNC_MASK, +}; + +static int call_home_on_panic(struct notifier_block *self, + unsigned long event, void *data) +{ + strncat(data, nodename, strlen(nodename)); + sclp_async_send_wait(data); + return NOTIFY_DONE; +} + +static struct notifier_block call_home_panic_nb = { + .notifier_call = call_home_on_panic, + .priority = INT_MAX, +}; + +static int proc_handler_callhome(ctl_table *ctl, int write, struct file *filp, + void __user *buffer, size_t *count, + loff_t *ppos) +{ + unsigned long val; + int len, rc; + char buf[2]; + + if (!*count | (*ppos && !write)) { + *count = 0; + return 0; + } + if (!write) { + len = sprintf(buf, "%d\n", callhome_enabled); + buf[len] = '\0'; + rc = copy_to_user(buffer, buf, sizeof(buf)); + if (rc != 0) + return -EFAULT; + } else { + len = *count; + rc = copy_from_user(buf, buffer, sizeof(buf)); + if (rc != 0) + return -EFAULT; + if (strict_strtoul(buf, 0, &val) != 0) + return -EINVAL; + if (val != 0 && val != 1) + return -EINVAL; + callhome_enabled = val; + } + *count = len; + *ppos += len; + return 0; +} + +static struct ctl_table callhome_table[] = { + { + .procname = "callhome", + .mode = 0644, + .proc_handler = &proc_handler_callhome, + }, + { .ctl_name = 0 } +}; + +static struct ctl_table kern_dir_table[] = { + { + .ctl_name = CTL_KERN, + .procname = "kernel", + .maxlen = 0, + .mode = 0555, + .child = callhome_table, + }, + { .ctl_name = 0 } +}; + +/* + * Function used to transfer asynchronous notification + * records which waits for send completion + */ +static int sclp_async_send_wait(char *message) +{ + struct async_evbuf *evb; + int rc; + unsigned long flags; + + if (!callhome_enabled) + return 0; + sccb->evbuf.header.type = EVTYP_ASYNC; + sccb->evbuf.rtype = 0xA5; + sccb->evbuf.otype = 0x00; + evb = &sccb->evbuf; + request->command = SCLP_CMDW_WRITE_EVENT_DATA; + request->sccb = sccb; + request->status = SCLP_REQ_FILLED; + strncpy(sccb->evbuf.data, message, sizeof(sccb->evbuf.data)); + /* + * Retain Queue + * e.g. 5639CC140 500 Red Hat RHEL5 Linux for zSeries (RHEL AS) + */ + strncpy(sccb->evbuf.comp_id, "000000000", sizeof(sccb->evbuf.comp_id)); + sccb->evbuf.header.length = sizeof(sccb->evbuf); + sccb->header.length = sizeof(sccb->evbuf) + sizeof(sccb->header); + sccb->header.function_code = SCLP_NORMAL_WRITE; + rc = sclp_add_request(request); + if (rc) + return rc; + spin_lock_irqsave(&sclp_async_lock, flags); + while (request->status != SCLP_REQ_DONE && + request->status != SCLP_REQ_FAILED) { + sclp_sync_wait(); + } + spin_unlock_irqrestore(&sclp_async_lock, flags); + if (request->status != SCLP_REQ_DONE) + return -EIO; + rc = ((struct sclp_async_sccb *) + request->sccb)->header.response_code; + if (rc != 0x0020) + return -EIO; + if (evb->header.flags != 0x80) + return -EIO; + return rc; +} + +static int __init sclp_async_init(void) +{ + int rc; + + rc = sclp_register(&sclp_async_register); + if (rc) + return rc; + callhome_sysctl_header = register_sysctl_table(kern_dir_table); + if (!callhome_sysctl_header) { + rc = -ENOMEM; + goto out_sclp; + } + if (!(sclp_async_register.sclp_receive_mask & EVTYP_ASYNC_MASK)) { + rc = -EOPNOTSUPP; + goto out_sclp; + } + rc = -ENOMEM; + request = kzalloc(sizeof(struct sclp_req), GFP_KERNEL); + if (!request) + goto out_sys; + sccb = (struct sclp_async_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA); + if (!sccb) + goto out_mem; + rc = atomic_notifier_chain_register(&panic_notifier_list, + &call_home_panic_nb); + if (rc) + goto out_mem; + + strncpy(nodename, init_utsname()->nodename, 64); + return 0; + +out_mem: + kfree(request); + free_page((unsigned long) sccb); +out_sys: + unregister_sysctl_table(callhome_sysctl_header); +out_sclp: + sclp_unregister(&sclp_async_register); + return rc; + +} +module_init(sclp_async_init); + +static void __exit sclp_async_exit(void) +{ + atomic_notifier_chain_unregister(&panic_notifier_list, + &call_home_panic_nb); + unregister_sysctl_table(callhome_sysctl_header); + sclp_unregister(&sclp_async_register); + free_page((unsigned long) sccb); + kfree(request); +} +module_exit(sclp_async_exit); + +MODULE_AUTHOR("Copyright IBM Corp. 2009"); +MODULE_AUTHOR("Hans-Joachim Picht <hans@linux.vnet.ibm.com>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("SCLP Asynchronous Notification Records"); |