[S390] s390_hypfs: Add new attributes
In order to access the data of the hypfs diagnose calls from user
space also in binary form, this patch adds two new attributes in
debugfs:
* z/VM: s390_hypfs/d2fc_bin
* LPAR: s390_hypfs/d204_bin
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/hypfs/hypfs_vm.c b/arch/s390/hypfs/hypfs_vm.c
index f0b0d31..ee5ab1a 100644
--- a/arch/s390/hypfs/hypfs_vm.c
+++ b/arch/s390/hypfs/hypfs_vm.c
@@ -10,14 +10,18 @@
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <asm/ebcdic.h>
+#include <asm/timex.h>
#include "hypfs.h"
#define NAME_LEN 8
+#define DBFS_D2FC_HDR_VERSION 0
static char local_guest[] = " ";
static char all_guests[] = "* ";
static char *guest_query;
+static struct dentry *dbfs_d2fc_file;
+
struct diag2fc_data {
__u32 version;
__u32 flags;
@@ -76,23 +80,26 @@
return -residual_cnt;
}
-static struct diag2fc_data *diag2fc_store(char *query, int *count)
+/*
+ * Allocate buffer for "query" and store diag 2fc at "offset"
+ */
+static void *diag2fc_store(char *query, unsigned int *count, int offset)
{
+ void *data;
int size;
- struct diag2fc_data *data;
do {
size = diag2fc(0, query, NULL);
if (size < 0)
return ERR_PTR(-EACCES);
- data = vmalloc(size);
+ data = vmalloc(size + offset);
if (!data)
return ERR_PTR(-ENOMEM);
- if (diag2fc(size, query, data) == 0)
+ if (diag2fc(size, query, data + offset) == 0)
break;
vfree(data);
} while (1);
- *count = (size / sizeof(*data));
+ *count = (size / sizeof(struct diag2fc_data));
return data;
}
@@ -168,9 +175,10 @@
{
struct dentry *dir, *file;
struct diag2fc_data *data;
- int rc, i, count = 0;
+ unsigned int count = 0;
+ int rc, i;
- data = diag2fc_store(guest_query, &count);
+ data = diag2fc_store(guest_query, &count, 0);
if (IS_ERR(data))
return PTR_ERR(data);
@@ -218,8 +226,61 @@
return rc;
}
+struct dbfs_d2fc_hdr {
+ u64 len; /* Length of d2fc buffer without header */
+ u16 version; /* Version of header */
+ char tod_ext[16]; /* TOD clock for d2fc */
+ u64 count; /* Number of VM guests in d2fc buffer */
+ char reserved[30];
+} __attribute__ ((packed));
+
+struct dbfs_d2fc {
+ struct dbfs_d2fc_hdr hdr; /* 64 byte header */
+ char buf[]; /* d2fc buffer */
+} __attribute__ ((packed));
+
+static int dbfs_d2fc_open(struct inode *inode, struct file *file)
+{
+ struct dbfs_d2fc *data;
+ unsigned int count;
+
+ data = diag2fc_store(guest_query, &count, sizeof(data->hdr));
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+ get_clock_ext(data->hdr.tod_ext);
+ data->hdr.len = count * sizeof(struct diag2fc_data);
+ data->hdr.version = DBFS_D2FC_HDR_VERSION;
+ data->hdr.count = count;
+ memset(&data->hdr.reserved, 0, sizeof(data->hdr.reserved));
+ file->private_data = data;
+ return nonseekable_open(inode, file);
+}
+
+static int dbfs_d2fc_release(struct inode *inode, struct file *file)
+{
+ diag2fc_free(file->private_data);
+ return 0;
+}
+
+static ssize_t dbfs_d2fc_read(struct file *file, char __user *buf,
+ size_t size, loff_t *ppos)
+{
+ struct dbfs_d2fc *data = file->private_data;
+
+ return simple_read_from_buffer(buf, size, ppos, data, data->hdr.len +
+ sizeof(struct dbfs_d2fc_hdr));
+}
+
+static const struct file_operations dbfs_d2fc_ops = {
+ .open = dbfs_d2fc_open,
+ .read = dbfs_d2fc_read,
+ .release = dbfs_d2fc_release,
+};
+
int hypfs_vm_init(void)
{
+ if (!MACHINE_IS_VM)
+ return 0;
if (diag2fc(0, all_guests, NULL) > 0)
guest_query = all_guests;
else if (diag2fc(0, local_guest, NULL) > 0)
@@ -227,5 +288,17 @@
else
return -EACCES;
+ dbfs_d2fc_file = debugfs_create_file("diag_2fc", 0400, hypfs_dbfs_dir,
+ NULL, &dbfs_d2fc_ops);
+ if (IS_ERR(dbfs_d2fc_file))
+ return PTR_ERR(dbfs_d2fc_file);
+
return 0;
}
+
+void hypfs_vm_exit(void)
+{
+ if (!MACHINE_IS_VM)
+ return;
+ debugfs_remove(dbfs_d2fc_file);
+}