2004-10-22 12:40:22

by Martin Schwidefsky

[permalink] [raw]
Subject: [patch 3/6] s390: dcss segments cleanup.

[patch 3/6] s390: dcss segments cleanup.

From: Carsten Otte <[email protected]>
From: Gerald Schaefer <[email protected]>

Cleanup segment load/unload infrastructure.

Signed-off-by: Martin Schwidefsky <[email protected]>

diffstat:
arch/s390/mm/extmem.c | 783 +++++++++++++++++++-----------------------
drivers/s390/block/dcssblk.c | 119 +++---
drivers/s390/char/monreader.c | 62 +++
include/asm-s390/extmem.h | 21 -
4 files changed, 518 insertions(+), 467 deletions(-)

diff -urN linux-2.6/arch/s390/mm/extmem.c linux-2.6-patched/arch/s390/mm/extmem.c
--- linux-2.6/arch/s390/mm/extmem.c 2004-10-18 23:54:40.000000000 +0200
+++ linux-2.6-patched/arch/s390/mm/extmem.c 2004-10-22 13:51:44.000000000 +0200
@@ -1,11 +1,10 @@
/*
- * File...........: arch/s390/mm/dcss.c
- * Author(s)......: Steven Shultz <[email protected]>
- * Carsten Otte <[email protected]>
+ * File...........: arch/s390/mm/extmem.c
+ * Author(s)......: Carsten Otte <[email protected]>
+ * Rob M van der Heij <[email protected]>
+ * Steven Shultz <[email protected]>
* Bugreports.to..: <[email protected]>
- * thanks to Rob M van der Heij
- * - he wrote the diag64 function
- * (C) IBM Corporation 2002
+ * (C) IBM Corporation 2002-2004
*/

#include <linux/kernel.h>
@@ -43,18 +42,38 @@
#define DCSS_SEGEXT 0x18
#define DCSS_QACTV 0x0c

+struct qout64 {
+ int segstart;
+ int segend;
+ int segcnt;
+ int segrcnt;
+ char segout[8][6];
+};
+
+struct qin64 {
+ char qopcode;
+ char rsrv1[3];
+ char qrcode;
+ char rsrv2[3];
+ char qname[8];
+ unsigned int qoutptr;
+ short int qoutlen;
+};
+
struct dcss_segment {
- struct list_head list;
- char dcss_name[8];
- unsigned long start_addr;
- unsigned long end;
- atomic_t ref_count;
- int dcss_attr;
- int shared_attr;
+ struct list_head list;
+ char dcss_name[8];
+ unsigned long start_addr;
+ unsigned long end;
+ atomic_t ref_count;
+ int do_nonshared;
+ int vm_segtype;
};

static spinlock_t dcss_lock = SPIN_LOCK_UNLOCKED;
static struct list_head dcss_list = LIST_HEAD_INIT(dcss_list);
+static char *segtype_string[7] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC" };
+
extern struct {
unsigned long addr, size, type;
} memory_chunk[MEMORY_CHUNKS];
@@ -63,20 +82,46 @@
* Create the 8 bytes, ebcdic VM segment name from
* an ascii name.
*/
-static void inline dcss_mkname(char *name, char *dcss_name)
+static void inline
+dcss_mkname(char *name, char *dcss_name)
{
- int i;
+ int i;

- for (i = 0; i <= 8; i++) {
- if (name[i] == '\0')
- break;
- dcss_name[i] = toupper(name[i]);
- };
- for (; i <= 8; i++)
- dcss_name[i] = ' ';
- ASCEBC(dcss_name, 8);
+ for (i = 0; i < 8; i++) {
+ if (name[i] == '\0')
+ break;
+ dcss_name[i] = toupper(name[i]);
+ };
+ for (; i < 8; i++)
+ dcss_name[i] = ' ';
+ ASCEBC(dcss_name, 8);
}

+
+/*
+ * search all segments in dcss_list, and return the one
+ * namend *name. If not found, return NULL.
+ */
+static struct dcss_segment *
+segment_by_name (char *name)
+{
+ char dcss_name[9];
+ struct list_head *l;
+ struct dcss_segment *tmp, *retval = NULL;
+
+ BUG_ON (!spin_is_locked(&dcss_lock));
+ dcss_mkname (name, dcss_name);
+ list_for_each (l, &dcss_list) {
+ tmp = list_entry (l, struct dcss_segment, list);
+ if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
+ retval = tmp;
+ break;
+ }
+ }
+ return retval;
+}
+
+
/*
* Perform a function on a dcss segment.
*/
@@ -84,337 +129,270 @@
dcss_diag (__u8 func, void *parameter,
unsigned long *ret1, unsigned long *ret2)
{
- unsigned long rx, ry;
- int rc;
+ unsigned long rx, ry;
+ int rc;

- rx = (unsigned long) parameter;
- ry = (unsigned long) func;
- __asm__ __volatile__(
+ rx = (unsigned long) parameter;
+ ry = (unsigned long) func;
+ __asm__ __volatile__(
#ifdef CONFIG_ARCH_S390X
- " sam31\n" // switch to 31 bit
- " diag %0,%1,0x64\n"
- " sam64\n" // switch back to 64 bit
+ " sam31\n" // switch to 31 bit
+ " diag %0,%1,0x64\n"
+ " sam64\n" // switch back to 64 bit
#else
- " diag %0,%1,0x64\n"
+ " diag %0,%1,0x64\n"
#endif
- " ipm %2\n"
- " srl %2,28\n"
- : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc" );
- *ret1 = rx;
- *ret2 = ry;
- return rc;
+ " ipm %2\n"
+ " srl %2,28\n"
+ : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc" );
+ *ret1 = rx;
+ *ret2 = ry;
+ return rc;
}

-
-/* use to issue "extended" dcss query */
static inline int
-dcss_diag_query(char *name, int *rwattr, int *shattr, unsigned long *segstart, unsigned long *segend)
+dcss_diag_translate_rc (int vm_rc) {
+ if (vm_rc == 44)
+ return -ENOENT;
+ return -EIO;
+}
+
+
+/* do a diag to get info about a segment.
+ * fills start_address, end and vm_segtype fields
+ */
+static int
+query_segment_info (struct dcss_segment *seg)
{
- int i,j,rc;
- unsigned long rx, ry;
+ struct qin64 *qin = kmalloc (sizeof(struct qin64), GFP_DMA);
+ struct qout64 *qout = kmalloc (sizeof(struct qout64), GFP_DMA);

- typedef struct segentry {
- char thisseg[8];
- } segentry;
-
- struct qout64 {
- int segstart;
- int segend;
- int segcnt;
- int segrcnt;
- segentry segout[6];
- };
-
- struct qin64 {
- char qopcode;
- char rsrv1[3];
- char qrcode;
- char rsrv2[3];
- char qname[8];
- unsigned int qoutptr;
- short int qoutlen;
- };
-
-
- struct qin64 *qinarea;
- struct qout64 *qoutarea;
-
- qinarea = (struct qin64*) get_zeroed_page (GFP_DMA);
- if (!qinarea) {
- rc =-ENOMEM;
- goto out;
- }
- qoutarea = (struct qout64*) get_zeroed_page (GFP_DMA);
- if (!qoutarea) {
- rc = -ENOMEM;
- free_page ((unsigned long) qinarea);
- goto out;
- }
- memset (qinarea,0,PAGE_SIZE);
- memset (qoutarea,0,PAGE_SIZE);
-
- qinarea->qopcode = DCSS_QACTV; /* do a query for active
- segments */
- qinarea->qoutptr = (unsigned long) qoutarea;
- qinarea->qoutlen = sizeof(struct qout64);
-
- /* Move segment name into double word aligned
- field and pad with blanks to 8 long.
- */
-
- for (i = j = 0 ; i < 8; i++) {
- qinarea->qname[i] = (name[j] == '\0') ? ' ' : name[j++];
- }
-
- /* name already in EBCDIC */
- /* ASCEBC ((void *)&qinarea.qname, 8); */
-
- /* set the assembler variables */
- rx = (unsigned long) qinarea;
- ry = DCSS_SEGEXT; /* this is extended function */
+ int diag_cc, rc;
+ unsigned long dummy, vmrc;

- /* issue diagnose x'64' */
- __asm__ __volatile__(
-#ifdef CONFIG_ARCH_S390X
- " sam31\n" // switch to 31 bit
- " diag %0,%1,0x64\n"
- " sam64\n" // switch back to 64 bit
-#else
- " diag %0,%1,0x64\n"
-#endif
- " ipm %2\n"
- " srl %2,28\n"
- : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc" );
-
- /* parse the query output area */
- *segstart=qoutarea->segstart;
- *segend=qoutarea->segend;
-
- if (rc > 1)
- {
- *rwattr = 2;
- *shattr = 2;
- rc = 0;
- goto free;
- }
-
- if (qoutarea->segcnt > 6)
- {
- *rwattr = 3;
- *shattr = 3;
- rc = 0;
- goto free;
- }
-
- *rwattr = 1;
- *shattr = 1;
-
- for (i=0; i < qoutarea->segrcnt; i++) {
- if (qoutarea->segout[i].thisseg[3] == 2 ||
- qoutarea->segout[i].thisseg[3] == 3 ||
- qoutarea->segout[i].thisseg[3] == 6 )
- *rwattr = 0;
- if (qoutarea->segout[i].thisseg[3] == 1 ||
- qoutarea->segout[i].thisseg[3] == 3 ||
- qoutarea->segout[i].thisseg[3] == 5 )
- *shattr = 0;
- } /* end of for statement */
- rc = 0;
- free:
- free_page ((unsigned long) qoutarea);
- free_page ((unsigned long) qinarea);
+ if ((qin == NULL) || (qout == NULL)) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
+
+ /* initialize diag input parameters */
+ qin->qopcode = DCSS_QACTV;
+ qin->qoutptr = (unsigned long) qout;
+ qin->qoutlen = sizeof(struct qout64);
+ memcpy (qin->qname, seg->dcss_name, 8);
+
+ diag_cc = dcss_diag (DCSS_SEGEXT, qin, &dummy, &vmrc);
+
+ if (diag_cc > 1) {
+ rc = dcss_diag_translate_rc (vmrc);
+ goto out_free;
+ }
+
+ if (qout->segcnt > 1) {
+ rc = -ENOTSUPP;
+ goto out_free;
+ }
+
+ /* analyze diag output and update seg */
+ seg->start_addr = qout->segstart;
+ seg->end = qout->segend;
+
+ seg->vm_segtype = qout->segout[0][3];
+
+ rc = 0;
+
+ out_free:
+ if (qin) kfree(qin);
+ if (qout) kfree(qout);
+ return rc;
+}
+
+/*
+ * check if the given segment collides with guest storage.
+ * returns 1 if this is the case, 0 if no collision was found
+ */
+static int
+segment_overlaps_storage(struct dcss_segment *seg)
+{
+ int i;
+
+ for (i=0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
+ if (memory_chunk[i].type != 0)
+ continue;
+ if ((memory_chunk[i].addr >> 20) > (seg->end >> 20))
+ continue;
+ if (((memory_chunk[i].addr + memory_chunk[i].size - 1) >> 20)
+ < (seg->start_addr >> 20))
+ continue;
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * check if segment collides with other segments that are currently loaded
+ * returns 1 if this is the case, 0 if no collision was found
+ */
+static int
+segment_overlaps_others (struct dcss_segment *seg)
+{
+ struct list_head *l;
+ struct dcss_segment *tmp;
+
+ BUG_ON (!spin_is_locked(&dcss_lock));
+ list_for_each(l, &dcss_list) {
+ tmp = list_entry(l, struct dcss_segment, list);
+ if ((tmp->start_addr >> 20) > (seg->end >> 20))
+ continue;
+ if ((tmp->end >> 20) < (seg->start_addr >> 20))
+ continue;
+ if (seg == tmp)
+ continue;
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * get info about a segment
+ * possible return values:
+ * -ENOSYS : we are not running on VM
+ * -EIO : could not perform query diagnose
+ * -ENOENT : no such segment
+ * -ENOTSUPP: multi-part segment cannot be used with linux
+ * -ENOSPC : segment cannot be used (overlaps with storage)
+ * -ENOMEM : out of memory
+ * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
+ */
+int
+segment_info (char* name)
+{
+ int rc;
+ struct dcss_segment seg;
+
+ if (!MACHINE_IS_VM)
+ return -ENOSYS;
+
+ dcss_mkname(name, seg.dcss_name);
+ rc = query_segment_info (&seg);
+ if (rc < 0)
+ return rc;
+ return seg.vm_segtype;
+}
+
+/*
+ * real segment loading function, called from segment_load
+ */
+static int
+__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
+{
+ struct dcss_segment *seg = kmalloc(sizeof(struct dcss_segment),
+ GFP_DMA);
+ int dcss_command, rc, diag_cc;
+
+ if (seg == NULL) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ dcss_mkname (name, seg->dcss_name);
+ rc = query_segment_info (seg);
+ if (rc < 0)
+ goto out_free;
+ if (segment_overlaps_storage(seg)) {
+ PRINT_WARN ("segment_load: not loading segment %s - overlaps"
+ " storage\n",name);
+ rc = -ENOSPC;
+ goto out_free;
+ }
+ if (segment_overlaps_others(seg)) {
+ PRINT_WARN ("segment_load: not loading segment %s - overlaps"
+ " other segments\n",name);
+ rc = -EBUSY;
+ goto out_free;
+ }
+ if (do_nonshared)
+ dcss_command = DCSS_LOADNSR;
+ else
+ dcss_command = DCSS_LOADNOLY;
+
+ diag_cc = dcss_diag(dcss_command, seg->dcss_name,
+ &seg->start_addr, &seg->end);
+ if (diag_cc > 1) {
+ PRINT_WARN ("segment_load: could not load segment %s - "
+ "diag returned error (%ld)\n",name,seg->end);
+ rc = dcss_diag_translate_rc (seg->end);
+ dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+ &seg->start_addr, &seg->end);
+ goto out_free;
+ }
+ seg->do_nonshared = do_nonshared;
+ atomic_set(&seg->ref_count, 1);
+ list_add(&seg->list, &dcss_list);
+ rc = seg->vm_segtype;
+ *addr = seg->start_addr;
+ *end = seg->end;
+ if (do_nonshared)
+ PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
+ "type %s in non-shared mode\n", name,
+ (void*)seg->start_addr, (void*)seg->end,
+ segtype_string[seg->vm_segtype]);
+ else
+ PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
+ "type %s in shared mode\n", name,
+ (void*)seg->start_addr, (void*)seg->end,
+ segtype_string[seg->vm_segtype]);
+ goto out;
+ out_free:
+ kfree (seg);
out:
- return rc;
+ return rc;
}

/*
- * Load a DCSS segment via the diag 0x64.
+ * this function loads a DCSS segment
+ * name : name of the DCSS
+ * do_nonshared : 0 indicates that the dcss should be shared with other linux images
+ * 1 indicates that the dcss should be exclusive for this linux image
+ * addr : will be filled with start address of the segment
+ * end : will be filled with end address of the segment
+ * return values:
+ * -ENOSYS : we are not running on VM
+ * -EIO : could not perform query or load diagnose
+ * -ENOENT : no such segment
+ * -ENOTSUPP: multi-part segment cannot be used with linux
+ * -ENOSPC : segment cannot be used (overlaps with storage)
+ * -EBUSY : segment can temporarily not be used (overlaps with dcss)
+ * -EPERM : segment is currently loaded with incompatible permissions
+ * -ENOMEM : out of memory
+ * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
*/
-int segment_load(char *name, int segtype, unsigned long *addr,
- unsigned long *end)
+int
+segment_load (char *name, int do_nonshared, unsigned long *addr,
+ unsigned long *end)
{
- char dcss_name[8];
- struct list_head *l;
- struct dcss_segment *seg, *tmp;
- unsigned long dummy;
- unsigned long segstart, segend;
- int rc = 0,i;
- int rwattr, shattr;
-
- if (!MACHINE_IS_VM)
- return -ENOSYS;
- dcss_mkname(name, dcss_name);
- /* search for the dcss in list of currently loaded segments */
- spin_lock(&dcss_lock);
- seg = NULL;
- list_for_each(l, &dcss_list) {
- tmp = list_entry(l, struct dcss_segment, list);
- if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
- seg = tmp;
- break;
- }
- }
-
- if (seg == NULL) {
- /* find out the attributes of this
- shared segment */
- dcss_diag_query(dcss_name, &rwattr, &shattr, &segstart, &segend);
- /* does segment collide with main memory? */
- for (i=0; i < MEMORY_CHUNKS; i++) {
- if (memory_chunk[i].type != 0)
- continue;
- if (memory_chunk[i].addr > segend)
- continue;
- if (memory_chunk[i].addr + memory_chunk[i].size <= segstart)
- continue;
- spin_unlock(&dcss_lock);
- return -ENOENT;
- }
- /* or does it collide with other (loaded) segments? */
- list_for_each(l, &dcss_list) {
- tmp = list_entry(l, struct dcss_segment, list);
- if ((segstart <= tmp->end && segstart >= tmp->start_addr) ||
- (segend <= tmp->end && segend >= tmp->start_addr) ||
- (segstart <= tmp->start_addr && segend >= tmp->end)) {
- PRINT_ERR("Segment Overlap!\n");
- spin_unlock(&dcss_lock);
- return -ENOENT;
- }
- }
-
- /* do case statement on segtype */
- /* if asking for shared ro,
- shared rw works */
- /* if asking for exclusive ro,
- exclusive rw works */
-
- switch(segtype) {
- case SEGMENT_SHARED_RO:
- if (shattr > 1 || rwattr > 1) {
- spin_unlock(&dcss_lock);
- return -ENOENT;
- } else {
- if (shattr == 0 && rwattr == 0)
- rc = SEGMENT_EXCLUSIVE_RO;
- if (shattr == 0 && rwattr == 1)
- rc = SEGMENT_EXCLUSIVE_RW;
- if (shattr == 1 && rwattr == 0)
- rc = SEGMENT_SHARED_RO;
- if (shattr == 1 && rwattr == 1)
- rc = SEGMENT_SHARED_RW;
- }
- break;
- case SEGMENT_SHARED_RW:
- if (shattr > 1 || rwattr != 1) {
- spin_unlock(&dcss_lock);
- return -ENOENT;
- } else {
- if (shattr == 0)
- rc = SEGMENT_EXCLUSIVE_RW;
- if (shattr == 1)
- rc = SEGMENT_SHARED_RW;
- }
- break;
-
- case SEGMENT_EXCLUSIVE_RO:
- if (shattr > 0 || rwattr > 1) {
- spin_unlock(&dcss_lock);
- return -ENOENT;
- } else {
- if (rwattr == 0)
- rc = SEGMENT_EXCLUSIVE_RO;
- if (rwattr == 1)
- rc = SEGMENT_EXCLUSIVE_RW;
- }
- break;
-
- case SEGMENT_EXCLUSIVE_RW:
-/* if (shattr != 0 || rwattr != 1) {
- spin_unlock(&dcss_lock);
- return -ENOENT;
- } else {
-*/
- rc = SEGMENT_EXCLUSIVE_RW;
-// }
- break;
-
- default:
- spin_unlock(&dcss_lock);
- return -ENOENT;
- } /* end switch */
-
- seg = kmalloc(sizeof(struct dcss_segment), GFP_DMA);
- if (seg != NULL) {
- memcpy(seg->dcss_name, dcss_name, 8);
- if (rc == SEGMENT_EXCLUSIVE_RW) {
- if (dcss_diag(DCSS_LOADNSR, seg->dcss_name,
- &seg->start_addr, &seg->end) == 0) {
- if (seg->end < max_low_pfn*PAGE_SIZE ) {
- atomic_set(&seg->ref_count, 1);
- list_add(&seg->list, &dcss_list);
- *addr = seg->start_addr;
- *end = seg->end;
- seg->dcss_attr = rc;
- if (shattr == 1 && rwattr == 1)
- seg->shared_attr = SEGMENT_SHARED_RW;
- else if (shattr == 1 && rwattr == 0)
- seg->shared_attr = SEGMENT_SHARED_RO;
- else
- seg->shared_attr = SEGMENT_EXCLUSIVE_RW;
- } else {
- dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);
- kfree (seg);
- rc = -ENOENT;
- }
- } else {
- kfree(seg);
- rc = -ENOENT;
- }
- goto out;
- }
- if (dcss_diag(DCSS_LOADNOLY, seg->dcss_name,
- &seg->start_addr, &seg->end) == 0) {
- if (seg->end < max_low_pfn*PAGE_SIZE ) {
- atomic_set(&seg->ref_count, 1);
- list_add(&seg->list, &dcss_list);
- *addr = seg->start_addr;
- *end = seg->end;
- seg->dcss_attr = rc;
- seg->shared_attr = rc;
- } else {
- dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);
- kfree (seg);
- rc = -ENOENT;
- }
- } else {
- kfree(seg);
- rc = -ENOENT;
- }
- } else rc = -ENOMEM;
- } else {
- /* found */
- if ((segtype == SEGMENT_EXCLUSIVE_RW) && (seg->dcss_attr != SEGMENT_EXCLUSIVE_RW)) {
- PRINT_ERR("Segment already loaded in other mode than EXCLUSIVE_RW!\n");
- rc = -EPERM;
- goto out;
- /* reload segment in exclusive mode */
-/* dcss_diag(DCSS_LOADNSR, seg->dcss_name,
- &seg->start_addr, &seg->end);
- seg->dcss_attr = SEGMENT_EXCLUSIVE_RW;*/
- }
- if ((segtype != SEGMENT_EXCLUSIVE_RW) && (seg->dcss_attr == SEGMENT_EXCLUSIVE_RW)) {
- PRINT_ERR("Segment already loaded in EXCLUSIVE_RW mode!\n");
- rc = -EPERM;
- goto out;
+ struct dcss_segment *seg;
+ int rc;
+
+ if (!MACHINE_IS_VM)
+ return -ENOSYS;
+
+ spin_lock (&dcss_lock);
+ seg = segment_by_name (name);
+ if (seg == NULL)
+ rc = __segment_load (name, do_nonshared, addr, end);
+ else {
+ if (do_nonshared == seg->do_nonshared) {
+ atomic_inc(&seg->ref_count);
+ *addr = seg->start_addr;
+ *end = seg->end;
+ rc = seg->vm_segtype;
+ } else {
+ *addr = *end = 0;
+ rc = -EPERM;
}
- atomic_inc(&seg->ref_count);
- *addr = seg->start_addr;
- *end = seg->end;
- rc = seg->dcss_attr;
- }
-out:
- spin_unlock(&dcss_lock);
- return rc;
+ }
+ spin_unlock (&dcss_lock);
+ return rc;
}

/*
@@ -422,84 +400,65 @@
* it from the address space if nobody is using it
* any longer.
*/
-void segment_unload(char *name)
+void
+segment_unload(char *name)
{
- char dcss_name[8];
- unsigned long dummy;
- struct list_head *l,*l_tmp;
- struct dcss_segment *seg;
-
- if (!MACHINE_IS_VM)
- return;
- dcss_mkname(name, dcss_name);
- spin_lock(&dcss_lock);
- list_for_each_safe(l, l_tmp, &dcss_list) {
- seg = list_entry(l, struct dcss_segment, list);
- if (memcmp(seg->dcss_name, dcss_name, 8) == 0) {
- if (atomic_dec_return(&seg->ref_count) == 0) {
- /* Last user of the segment is
- gone. */
- list_del(&seg->list);
- dcss_diag(DCSS_PURGESEG, seg->dcss_name,
- &dummy, &dummy);
- kfree(seg);
- }
- break;
- }
- }
- spin_unlock(&dcss_lock);
-}
-
-/*
- * Replace an existing DCSS segment, so that machines
- * that load it anew will see the new version.
- */
-void segment_replace(char *name)
-{
- char dcss_name[8];
- struct list_head *l;
- struct dcss_segment *seg;
- int mybeg = 0;
- int myend = 0;
- char mybuff1[80];
- char mybuff2[80];
-
- if (!MACHINE_IS_VM)
- return;
- dcss_mkname(name, dcss_name);
-
- memset (mybuff1, 0, sizeof(mybuff1));
- memset (mybuff2, 0, sizeof(mybuff2));
-
- spin_lock(&dcss_lock);
- list_for_each(l, &dcss_list) {
- seg = list_entry(l, struct dcss_segment, list);
- if (memcmp(seg->dcss_name, dcss_name, 8) == 0) {
- mybeg = seg->start_addr >> 12;
- myend = (seg->end) >> 12;
- if (seg->shared_attr == SEGMENT_EXCLUSIVE_RW)
- sprintf(mybuff1, "DEFSEG %s %X-%X EW",
- name, mybeg, myend);
- if (seg->shared_attr == SEGMENT_EXCLUSIVE_RO)
- sprintf(mybuff1, "DEFSEG %s %X-%X RO",
- name, mybeg, myend);
- if (seg->shared_attr == SEGMENT_SHARED_RW)
- sprintf(mybuff1, "DEFSEG %s %X-%X SW",
- name, mybeg, myend);
- if (seg->shared_attr == SEGMENT_SHARED_RO)
- sprintf(mybuff1, "DEFSEG %s %X-%X SR",
- name, mybeg, myend);
- spin_unlock(&dcss_lock);
- sprintf(mybuff2, "SAVESEG %s", name);
- cpcmd(mybuff1, NULL, 80);
- cpcmd(mybuff2, NULL, 80);
- break;
- }
+ unsigned long dummy;
+ struct dcss_segment *seg;
+
+ if (!MACHINE_IS_VM)
+ return;
+
+ spin_lock(&dcss_lock);
+ seg = segment_by_name (name);
+ if (seg == NULL) {
+ PRINT_ERR ("could not find segment %s in segment_unload, "
+ "please report to [email protected]\n",name);
+ goto out_unlock;
+ }
+ if (atomic_dec_return(&seg->ref_count) == 0) {
+ list_del(&seg->list);
+ dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+ &dummy, &dummy);
+ kfree(seg);
+ }
+out_unlock:
+ spin_unlock(&dcss_lock);
+}

- }
- if (myend == 0) spin_unlock(&dcss_lock);
+/*
+ * save segment content permanently
+ */
+void segment_save(char *name)
+{
+ struct dcss_segment *seg;
+ int startpfn = 0;
+ int endpfn = 0;
+ char cmd1[80];
+ char cmd2[80];
+
+ if (!MACHINE_IS_VM)
+ return;
+
+ spin_lock(&dcss_lock);
+ seg = segment_by_name (name);
+
+ if (seg == NULL) {
+ PRINT_ERR ("could not find segment %s in segment_save, please report to [email protected]\n",name);
+ return;
+ }
+
+ startpfn = seg->start_addr >> 12;
+ endpfn = (seg->end) >> 12;
+ sprintf(cmd1, "DEFSEG %s %X-%X %s", name, startpfn, endpfn,
+ segtype_string[seg->vm_segtype]);
+ sprintf(cmd2, "SAVESEG %s", name);
+ cpcmd(cmd1, NULL, 80);
+ cpcmd(cmd2, NULL, 80);
+ spin_unlock(&dcss_lock);
}

EXPORT_SYMBOL(segment_load);
EXPORT_SYMBOL(segment_unload);
-EXPORT_SYMBOL(segment_replace);
+EXPORT_SYMBOL(segment_save);
+EXPORT_SYMBOL(segment_info);
diff -urN linux-2.6/drivers/s390/block/dcssblk.c linux-2.6-patched/drivers/s390/block/dcssblk.c
--- linux-2.6/drivers/s390/block/dcssblk.c 2004-10-18 23:53:43.000000000 +0200
+++ linux-2.6-patched/drivers/s390/block/dcssblk.c 2004-10-22 13:51:44.000000000 +0200
@@ -140,6 +140,53 @@
}

/*
+ * print appropriate error message for segment_load()/segment_info()
+ * return code
+ */
+static void
+dcssblk_segment_warn(int rc, char* seg_name)
+{
+ switch (rc) {
+ case -ENOENT:
+ PRINT_WARN("cannot load/query segment %s, does not exist\n",
+ seg_name);
+ break;
+ case -ENOSYS:
+ PRINT_WARN("cannot load/query segment %s, not running on VM\n",
+ seg_name);
+ break;
+ case -EIO:
+ PRINT_WARN("cannot load/query segment %s, hardware error\n",
+ seg_name);
+ break;
+ case -ENOTSUPP:
+ PRINT_WARN("cannot load/query segment %s, is a multi-part "
+ "segment\n", seg_name);
+ break;
+ case -ENOSPC:
+ PRINT_WARN("cannot load/query segment %s, overlaps with "
+ "storage\n", seg_name);
+ break;
+ case -EBUSY:
+ PRINT_WARN("cannot load/query segment %s, overlaps with "
+ "already loaded dcss\n", seg_name);
+ break;
+ case -EPERM:
+ PRINT_WARN("cannot load/query segment %s, already loaded in "
+ "incompatible mode\n", seg_name);
+ break;
+ case -ENOMEM:
+ PRINT_WARN("cannot load/query segment %s, out of memory\n",
+ seg_name);
+ break;
+ default:
+ PRINT_WARN("cannot load/query segment %s, return value %i\n",
+ seg_name, rc);
+ break;
+ }
+}
+
+/*
* device attribute for switching shared/nonshared (exclusive)
* operation (show + store)
*/
@@ -185,61 +232,38 @@
if (inbuf[0] == '1') {
// reload segment in shared mode
segment_unload(dev_info->segment_name);
- rc = segment_load(dev_info->segment_name, SEGMENT_SHARED_RO,
+ rc = segment_load(dev_info->segment_name, SEGMENT_SHARED,
&dev_info->start, &dev_info->end);
if (rc < 0) {
- PRINT_ERR("Segment %s not reloaded, rc=%d\n",
- dev_info->segment_name, rc);
+ dcssblk_segment_warn(rc, dev_info->segment_name);
goto removeseg;
}
dev_info->is_shared = 1;
- PRINT_INFO("Segment %s reloaded, shared mode.\n",
- dev_info->segment_name);
+ if (rc == SEG_TYPE_SR || rc == SEG_TYPE_ER || rc == SEG_TYPE_SC)
+ set_disk_ro(dev_info->gd, 1);
} else if (inbuf[0] == '0') {
// reload segment in exclusive mode
+ if (dev_info->segment_type == SEG_TYPE_SC) {
+ PRINT_ERR("Segment type SC (%s) cannot be loaded in "
+ "non-shared mode\n", dev_info->segment_name);
+ up_write(&dcssblk_devices_sem);
+ return -EINVAL;
+ }
segment_unload(dev_info->segment_name);
- rc = segment_load(dev_info->segment_name, SEGMENT_EXCLUSIVE_RW,
+ rc = segment_load(dev_info->segment_name, SEGMENT_EXCLUSIVE,
&dev_info->start, &dev_info->end);
if (rc < 0) {
- PRINT_ERR("Segment %s not reloaded, rc=%d\n",
- dev_info->segment_name, rc);
+ dcssblk_segment_warn(rc, dev_info->segment_name);
goto removeseg;
}
dev_info->is_shared = 0;
- PRINT_INFO("Segment %s reloaded, exclusive (read-write) mode.\n",
- dev_info->segment_name);
+ set_disk_ro(dev_info->gd, 0);
} else {
up_write(&dcssblk_devices_sem);
PRINT_WARN("Invalid value, must be 0 or 1\n");
return -EINVAL;
}
- dev_info->segment_type = rc;
rc = count;
-
- switch (dev_info->segment_type) {
- case SEGMENT_SHARED_RO:
- case SEGMENT_EXCLUSIVE_RO:
- set_disk_ro(dev_info->gd, 1);
- break;
- case SEGMENT_SHARED_RW:
- case SEGMENT_EXCLUSIVE_RW:
- set_disk_ro(dev_info->gd, 0);
- break;
- }
- if ((inbuf[0] == '1') &&
- ((dev_info->segment_type == SEGMENT_EXCLUSIVE_RO) ||
- (dev_info->segment_type == SEGMENT_EXCLUSIVE_RW))) {
- PRINT_WARN("Could not get shared copy of segment %s\n",
- dev_info->segment_name);
- rc = -EPERM;
- }
- if ((inbuf[0] == '0') &&
- ((dev_info->segment_type == SEGMENT_SHARED_RO) ||
- (dev_info->segment_type == SEGMENT_SHARED_RW))) {
- PRINT_WARN("Could not get exclusive copy of segment %s\n",
- dev_info->segment_name);
- rc = -EPERM;
- }
up_write(&dcssblk_devices_sem);
goto out;

@@ -292,7 +316,7 @@
// device is idle => we save immediately
PRINT_INFO("Saving segment %s\n",
dev_info->segment_name);
- segment_replace(dev_info->segment_name);
+ segment_save(dev_info->segment_name);
} else {
// device is busy => we save it when it becomes
// idle in dcssblk_release
@@ -390,18 +414,17 @@
/*
* load the segment
*/
- rc = segment_load(local_buf, SEGMENT_SHARED_RO,
+ rc = segment_load(local_buf, SEGMENT_SHARED,
&dev_info->start, &dev_info->end);
if (rc < 0) {
- PRINT_ERR("Segment %s not loaded, rc=%d\n", local_buf, rc);
+ dcssblk_segment_warn(rc, dev_info->segment_name);
goto dealloc_gendisk;
}
seg_byte_size = (dev_info->end - dev_info->start + 1);
set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors
- PRINT_INFO("Loaded segment %s from %p to %p, size = %lu Byte, "
- "capacity = %lu sectors (512 Byte)\n", local_buf,
- (void *) dev_info->start, (void *) dev_info->end,
- seg_byte_size, seg_byte_size >> 9);
+ PRINT_INFO("Loaded segment %s, size = %lu Byte, "
+ "capacity = %lu (512 Byte) sectors\n", local_buf,
+ seg_byte_size, seg_byte_size >> 9);

dev_info->segment_type = rc;
dev_info->save_pending = 0;
@@ -451,12 +474,12 @@
blk_queue_hardsect_size(dev_info->dcssblk_queue, 4096);

switch (dev_info->segment_type) {
- case SEGMENT_SHARED_RO:
- case SEGMENT_EXCLUSIVE_RO:
+ case SEG_TYPE_SR:
+ case SEG_TYPE_ER:
+ case SEG_TYPE_SC:
set_disk_ro(dev_info->gd,1);
break;
- case SEGMENT_SHARED_RW:
- case SEGMENT_EXCLUSIVE_RW:
+ default:
set_disk_ro(dev_info->gd,0);
break;
}
@@ -589,7 +612,7 @@
&& (dev_info->save_pending)) {
PRINT_INFO("Segment %s became idle and is being saved now\n",
dev_info->segment_name);
- segment_replace(dev_info->segment_name);
+ segment_save(dev_info->segment_name);
dev_info->save_pending = 0;
}
up_write(&dcssblk_devices_sem);
diff -urN linux-2.6/drivers/s390/char/monreader.c linux-2.6-patched/drivers/s390/char/monreader.c
--- linux-2.6/drivers/s390/char/monreader.c 2004-10-22 13:51:36.000000000 +0200
+++ linux-2.6-patched/drivers/s390/char/monreader.c 2004-10-22 13:51:44.000000000 +0200
@@ -115,6 +115,53 @@
ASCEBC(ebcdic_name, 8);
}

+/*
+ * print appropriate error message for segment_load()/segment_info()
+ * return code
+ */
+static void
+mon_segment_warn(int rc, char* seg_name)
+{
+ switch (rc) {
+ case -ENOENT:
+ P_WARNING("cannot load/query segment %s, does not exist\n",
+ seg_name);
+ break;
+ case -ENOSYS:
+ P_WARNING("cannot load/query segment %s, not running on VM\n",
+ seg_name);
+ break;
+ case -EIO:
+ P_WARNING("cannot load/query segment %s, hardware error\n",
+ seg_name);
+ break;
+ case -ENOTSUPP:
+ P_WARNING("cannot load/query segment %s, is a multi-part "
+ "segment\n", seg_name);
+ break;
+ case -ENOSPC:
+ P_WARNING("cannot load/query segment %s, overlaps with "
+ "storage\n", seg_name);
+ break;
+ case -EBUSY:
+ P_WARNING("cannot load/query segment %s, overlaps with "
+ "already loaded dcss\n", seg_name);
+ break;
+ case -EPERM:
+ P_WARNING("cannot load/query segment %s, already loaded in "
+ "incompatible mode\n", seg_name);
+ break;
+ case -ENOMEM:
+ P_WARNING("cannot load/query segment %s, out of memory\n",
+ seg_name);
+ break;
+ default:
+ P_WARNING("cannot load/query segment %s, return value %i\n",
+ seg_name, rc);
+ break;
+ }
+}
+
static inline unsigned long
mon_mca_start(struct mon_msg *monmsg)
{
@@ -534,10 +581,21 @@
return -ENODEV;
}

- rc = segment_load(mon_dcss_name, SEGMENT_SHARED_RO,
+ rc = segment_info(mon_dcss_name);
+ if (rc < 0) {
+ mon_segment_warn(rc, mon_dcss_name);
+ return rc;
+ }
+ if (rc != SEG_TYPE_SC) {
+ P_ERROR("segment %s has unsupported type, should be SC\n",
+ mon_dcss_name);
+ return -EINVAL;
+ }
+
+ rc = segment_load(mon_dcss_name, SEGMENT_SHARED,
&mon_dcss_start, &mon_dcss_end);
if (rc < 0) {
- P_ERROR("Segment %s not loaded, rc = %d\n", mon_dcss_name, rc);
+ mon_segment_warn(rc, mon_dcss_name);
return -EINVAL;
}
dcss_mkname(mon_dcss_name, &user_data_connect[8]);
diff -urN linux-2.6/include/asm-s390/extmem.h linux-2.6-patched/include/asm-s390/extmem.h
--- linux-2.6/include/asm-s390/extmem.h 2004-10-18 23:54:39.000000000 +0200
+++ linux-2.6-patched/include/asm-s390/extmem.h 2004-10-22 13:51:44.000000000 +0200
@@ -8,12 +8,23 @@
#ifndef _ASM_S390X_DCSS_H
#define _ASM_S390X_DCSS_H
#ifndef __ASSEMBLY__
-#define SEGMENT_SHARED_RW 0
-#define SEGMENT_SHARED_RO 1
-#define SEGMENT_EXCLUSIVE_RW 2
-#define SEGMENT_EXCLUSIVE_RO 3
+
+/* possible values for segment type as returned by segment_info */
+#define SEG_TYPE_SW 0
+#define SEG_TYPE_EW 1
+#define SEG_TYPE_SR 2
+#define SEG_TYPE_ER 3
+#define SEG_TYPE_SN 4
+#define SEG_TYPE_EN 5
+#define SEG_TYPE_SC 6
+
+#define SEGMENT_SHARED 0
+#define SEGMENT_EXCLUSIVE 1
+
extern int segment_load (char *name,int segtype,unsigned long *addr,unsigned long *length);
extern void segment_unload(char *name);
-extern void segment_replace(char *name);
+extern void segment_save(char *name);
+extern int segment_info (char* name);
+
#endif
#endif