X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fs390%2Fmm%2Fcmm.c;h=cb29503010616dc3afbe66074df8eb853ab238d9;hb=9bf4aaab3e101692164d49b7ca357651eb691cb6;hp=095a5648c1cfc5a4bbd78f8c650640df1bb4f465;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git

diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
index 095a5648c..cb2950301 100644
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -19,6 +19,7 @@
 
 #include <asm/pgalloc.h>
 #include <asm/uaccess.h>
+#include <asm/smp.h>
 
 #include "../../../drivers/s390/net/smsgiucv.h"
 
@@ -255,13 +256,13 @@ static struct ctl_table cmm_table[];
 
 static int
 cmm_pages_handler(ctl_table *ctl, int write, struct file *filp,
-		  void *buffer, size_t *lenp)
+		  void *buffer, size_t *lenp, loff_t *ppos)
 {
 	char buf[16], *p;
 	long pages;
 	int len;
 
-	if (!*lenp || (filp->f_pos && !write)) {
+	if (!*lenp || (*ppos && !write)) {
 		*lenp = 0;
 		return 0;
 	}
@@ -290,19 +291,19 @@ cmm_pages_handler(ctl_table *ctl, int write, struct file *filp,
 			return -EFAULT;
 	}
 	*lenp = len;
-	filp->f_pos += len;
+	*ppos += len;
 	return 0;
 }
 
 static int
 cmm_timeout_handler(ctl_table *ctl, int write, struct file *filp,
-		    void *buffer, size_t *lenp)
+		    void *buffer, size_t *lenp, loff_t *ppos)
 {
 	char buf[64], *p;
 	long pages, seconds;
 	int len;
 
-	if (!*lenp || (filp->f_pos && !write)) {
+	if (!*lenp || (*ppos && !write)) {
 		*lenp = 0;
 		return 0;
 	}
@@ -327,7 +328,7 @@ cmm_timeout_handler(ctl_table *ctl, int write, struct file *filp,
 			return -EFAULT;
 	}
 	*lenp = len;
-	filp->f_pos += len;
+	*ppos += len;
 	return 0;
 }
 
@@ -407,6 +408,14 @@ struct ctl_table_header *cmm_sysctl_header;
 static int
 cmm_init (void)
 {
+	int rc;
+
+	/* Prevent logical cpu 0 from being set offline. */
+	rc = smp_get_cpu(cpumask_of_cpu(0));
+	if (rc) {
+		printk(KERN_ERR "CMM: unable to reserve cpu 0\n");
+		return rc;
+	}
 #ifdef CONFIG_CMM_PROC
 	cmm_sysctl_header = register_sysctl_table(cmm_dir_table, 1);
 #endif
@@ -430,6 +439,8 @@ cmm_exit(void)
 #ifdef CONFIG_CMM_IUCV
 	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
 #endif
+	/* Allow logical cpu 0 to be set offline again. */
+	smp_put_cpu(0);
 }
 
 module_init(cmm_init);