diff options
Diffstat (limited to 'kernel/utsname_sysctl.c')
| -rw-r--r-- | kernel/utsname_sysctl.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c index a2cd77e70d4..c8eac43267e 100644 --- a/kernel/utsname_sysctl.c +++ b/kernel/utsname_sysctl.c @@ -9,12 +9,15 @@ * License. */ -#include <linux/module.h> +#include <linux/export.h> #include <linux/uts.h> #include <linux/utsname.h> #include <linux/sysctl.h> +#include <linux/wait.h> -static void *get_uts(ctl_table *table, int write) +#ifdef CONFIG_PROC_SYSCTL + +static void *get_uts(struct ctl_table *table, int write) { char *which = table->data; struct uts_namespace *uts_ns; @@ -29,7 +32,7 @@ static void *get_uts(ctl_table *table, int write) return which; } -static void put_uts(ctl_table *table, int write, void *which) +static void put_uts(struct ctl_table *table, int write, void *which) { if (!write) up_read(&uts_sem); @@ -37,26 +40,32 @@ static void put_uts(ctl_table *table, int write, void *which) up_write(&uts_sem); } -#ifdef CONFIG_PROC_SYSCTL /* * Special case of dostring for the UTS structure. This has locks * to observe. Should this be in kernel/sys.c ???? */ -static int proc_do_uts_string(ctl_table *table, int write, +static int proc_do_uts_string(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table uts_table; int r; memcpy(&uts_table, table, sizeof(uts_table)); uts_table.data = get_uts(table, write); - r = proc_dostring(&uts_table,write,buffer,lenp, ppos); + r = proc_dostring(&uts_table, write, buffer, lenp, ppos); put_uts(table, write, uts_table.data); + + if (write) + proc_sys_poll_notify(table->poll); + return r; } #else #define proc_do_uts_string NULL #endif +static DEFINE_CTL_TABLE_POLL(hostname_poll); +static DEFINE_CTL_TABLE_POLL(domainname_poll); + static struct ctl_table uts_kern_table[] = { { .procname = "ostype", @@ -85,6 +94,7 @@ static struct ctl_table uts_kern_table[] = { .maxlen = sizeof(init_uts_ns.name.nodename), .mode = 0644, .proc_handler = proc_do_uts_string, + .poll = &hostname_poll, }, { .procname = "domainname", @@ -92,6 +102,7 @@ static struct ctl_table uts_kern_table[] = { .maxlen = sizeof(init_uts_ns.name.domainname), .mode = 0644, .proc_handler = proc_do_uts_string, + .poll = &domainname_poll, }, {} }; @@ -105,10 +116,23 @@ static struct ctl_table uts_root_table[] = { {} }; +#ifdef CONFIG_PROC_SYSCTL +/* + * Notify userspace about a change in a certain entry of uts_kern_table, + * identified by the parameter proc. + */ +void uts_proc_notify(enum uts_proc proc) +{ + struct ctl_table *table = &uts_kern_table[proc]; + + proc_sys_poll_notify(table->poll); +} +#endif + static int __init utsname_sysctl_init(void) { register_sysctl_table(uts_root_table); return 0; } -__initcall(utsname_sysctl_init); +device_initcall(utsname_sysctl_init); |