[patch 3/10] s390: dasd driver.
From: Stefan Weinhuber <[email protected]>
dasd driver changes:
- Fix parameter parsing to allow sequences of devices, ranges
and keywords.
Signed-off-by: Martin Schwidefsky <[email protected]>
diffstat:
drivers/s390/block/dasd_devmap.c | 170 +++++++++++++++++++++++----------------
1 files changed, 103 insertions(+), 67 deletions(-)
diff -urN linux-2.6/drivers/s390/block/dasd_devmap.c linux-2.6-patched/drivers/s390/block/dasd_devmap.c
--- linux-2.6/drivers/s390/block/dasd_devmap.c 2004-10-18 23:54:27.000000000 +0200
+++ linux-2.6-patched/drivers/s390/block/dasd_devmap.c 2004-11-11 15:06:55.000000000 +0100
@@ -11,7 +11,7 @@
* functions may not be called from interrupt context. In particular
* dasd_get_device is a no-no from interrupt context.
*
- * $Revision: 1.30 $
+ * $Revision: 1.33 $
*/
#include <linux/config.h>
@@ -204,94 +204,130 @@
}
/*
- * Read comma separated list of dasd ranges.
+ * Try to match the first element on the comma separated parse string
+ * with one of the known keywords. If a keyword is found, take the approprate
+ * action and return a pointer to the residual string. If the first element
+ * could not be matched to any keyword then return an error code.
+ */
+static char *
+dasd_parse_keyword( char *parsestring ) {
+
+ char *nextcomma, *residual_str;
+ int length;
+
+ nextcomma = strchr(parsestring,',');
+ if (nextcomma) {
+ length = nextcomma - parsestring;
+ residual_str = nextcomma + 1;
+ } else {
+ length = strlen(parsestring);
+ residual_str = parsestring + length;
+ }
+ if (strncmp ("autodetect", parsestring, length) == 0) {
+ dasd_autodetect = 1;
+ MESSAGE (KERN_INFO, "%s",
+ "turning to autodetection mode");
+ return residual_str;
+ }
+ if (strncmp ("probeonly", parsestring, length) == 0) {
+ dasd_probeonly = 1;
+ MESSAGE(KERN_INFO, "%s",
+ "turning to probeonly mode");
+ return residual_str;
+ }
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Try to interprete the first element on the comma separated parse string
+ * as a device number or a range of devices. If the interpretation is
+ * successfull, create the matching dasd_devmap entries and return a pointer
+ * to the residual string.
+ * If interpretation fails or in case of an error, return an error code.
*/
-static inline int
-dasd_ranges_list(char *str)
-{
+static char *
+dasd_parse_range( char *parsestring ) {
+
struct dasd_devmap *devmap;
int from, from_id0, from_id1;
int to, to_id0, to_id1;
int features, rc;
- char bus_id[BUS_ID_SIZE+1], *orig_str;
+ char bus_id[BUS_ID_SIZE+1], *str;
- orig_str = str;
- while (1) {
- rc = dasd_busid(&str, &from_id0, &from_id1, &from);
- if (rc == 0) {
- to = from;
- to_id0 = from_id0;
- to_id1 = from_id1;
- if (*str == '-') {
- str++;
- rc = dasd_busid(&str, &to_id0, &to_id1, &to);
- }
- }
- if (rc == 0 &&
- (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
- rc = -EINVAL;
- if (rc) {
- MESSAGE(KERN_ERR, "Invalid device range %s", orig_str);
- return rc;
+ str = parsestring;
+ rc = dasd_busid(&str, &from_id0, &from_id1, &from);
+ if (rc == 0) {
+ to = from;
+ to_id0 = from_id0;
+ to_id1 = from_id1;
+ if (*str == '-') {
+ str++;
+ rc = dasd_busid(&str, &to_id0, &to_id1, &to);
}
- features = dasd_feature_list(str, &str);
- if (features < 0)
- return -EINVAL;
- while (from <= to) {
- sprintf(bus_id, "%01x.%01x.%04x",
- from_id0, from_id1, from++);
- devmap = dasd_add_busid(bus_id, features);
- if (IS_ERR(devmap))
- return PTR_ERR(devmap);
- }
- if (*str != ',')
- break;
- str++;
- }
- if (*str != '\0') {
- MESSAGE(KERN_WARNING,
- "junk at end of dasd parameter string: %s\n", str);
- return -EINVAL;
- }
- return 0;
-}
-
-/*
- * Parse a single dasd= parameter.
- */
-static int
-dasd_parameter(char *str)
-{
- if (strcmp ("autodetect", str) == 0) {
- dasd_autodetect = 1;
- MESSAGE (KERN_INFO, "%s",
- "turning to autodetection mode");
- return 0;
}
- if (strcmp ("probeonly", str) == 0) {
- dasd_probeonly = 1;
- MESSAGE(KERN_INFO, "%s",
- "turning to probeonly mode");
- return 0;
+ if (rc == 0 &&
+ (from_id0 != to_id0 || from_id1 != to_id1 || from > to))
+ rc = -EINVAL;
+ if (rc) {
+ MESSAGE(KERN_ERR, "Invalid device range %s", parsestring);
+ return ERR_PTR(rc);
}
- /* turn off autodetect mode and scan for dasd ranges */
- dasd_autodetect = 0;
- return dasd_ranges_list(str);
+ features = dasd_feature_list(str, &str);
+ if (features < 0)
+ return ERR_PTR(-EINVAL);
+ while (from <= to) {
+ sprintf(bus_id, "%01x.%01x.%04x",
+ from_id0, from_id1, from++);
+ devmap = dasd_add_busid(bus_id, features);
+ if (IS_ERR(devmap))
+ return (char *)devmap;
+ }
+ if (*str == ',')
+ return str + 1;
+ if (*str == '\0')
+ return str;
+ MESSAGE(KERN_WARNING,
+ "junk at end of dasd parameter string: %s\n", str);
+ return ERR_PTR(-EINVAL);
+}
+
+static inline char *
+dasd_parse_next_element( char *parsestring ) {
+ char * residual_str;
+ residual_str = dasd_parse_keyword(parsestring);
+ if (!IS_ERR(residual_str))
+ return residual_str;
+ residual_str = dasd_parse_range(parsestring);
+ return residual_str;
}
/*
- * Parse parameters stored in dasd[] and dasd_disciplines[].
+ * Parse parameters stored in dasd[]
+ * The 'dasd=...' parameter allows to specify a comma separated list of
+ * keywords and device ranges. When the dasd driver is build into the kernel,
+ * the complete list will be stored as one element of the dasd[] array.
+ * When the dasd driver is build as a module, then the list is broken into
+ * it's elements and each dasd[] entry contains one element.
*/
int
dasd_parse(void)
{
int rc, i;
+ char *parsestring;
rc = 0;
for (i = 0; i < 256; i++) {
if (dasd[i] == NULL)
break;
- rc = dasd_parameter(dasd[i]);
+ parsestring = dasd[i];
+ /* loop over the comma separated list in the parsestring */
+ while (*parsestring) {
+ parsestring = dasd_parse_next_element(parsestring);
+ if(IS_ERR(parsestring)) {
+ rc = PTR_ERR(parsestring);
+ break;
+ }
+ }
if (rc) {
DBF_EVENT(DBF_ALERT, "%s", "invalid range found");
break;