Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * File...........: arch/s390/mm/extmem.c

 * Author(s)......: Carsten Otte <cotte@de.ibm.com>

 *                  Rob M van der Heij <rvdheij@nl.ibm.com>

 *                  Steven Shultz <shultzss@us.ibm.com>

 * Bugreports.to..: <Linux390@de.ibm.com>

 * (C) IBM Corporation 2002-2004

 */

#include <linux/kernel.h>

#include <linux/string.h>

#include <linux/spinlock.h>

#include <linux/list.h>

#include <linux/slab.h>

#include <linux/module.h>

#include <linux/bootmem.h>

#include <linux/ctype.h>

#include <linux/ioport.h>

#include <asm/page.h>

#include <asm/pgtable.h>

#include <asm/ebcdic.h>

#include <asm/errno.h>

#include <asm/extmem.h>

#include <asm/cpcmd.h>

#include <asm/setup.h>

#define DCSS_DEBUG      /* Debug messages on/off */

#define DCSS_NAME "extmem"

#ifdef DCSS_DEBUG

#define PRINT_DEBUG(x...)       printk(KERN_DEBUG DCSS_NAME " debug:" x)

#else

#define PRINT_DEBUG(x...)   do {} while (0)

#endif

#define PRINT_INFO(x...)        printk(KERN_INFO DCSS_NAME " info:" x)

#define PRINT_WARN(x...)        printk(KERN_WARNING DCSS_NAME " warning:" x)

#define PRINT_ERR(x...)         printk(KERN_ERR DCSS_NAME " error:" x)

#define DCSS_LOADSHR    0x00

#define DCSS_LOADNSR    0x04

#define DCSS_PURGESEG   0x08

#define DCSS_FINDSEG    0x0c

#define DCSS_LOADNOLY   0x10

#define DCSS_SEGEXT     0x18

#define DCSS_FINDSEGA   0x0c

struct qrange {

        unsigned int  start; // 3byte start address, 1 byte type

        unsigned int  end;   // 3byte end address, 1 byte reserved

};

struct qout64 {

        int segstart;

        int segend;

        int segcnt;

        int segrcnt;

        struct qrange range[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];

        char res_name[15];

        unsigned long start_addr;

        unsigned long end;

        atomic_t ref_count;

        int do_nonshared;

        unsigned int vm_segtype;

        struct qrange range[6];

        int segcnt;

        struct resource *res;

};

static DEFINE_MUTEX(dcss_lock);

static struct list_head dcss_list = LIST_HEAD_INIT(dcss_list);

static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",

                                        "EW/EN-MIXED" };

/*

 * Create the 8 bytes, ebcdic VM segment name from

 * an ascii name.

 */

static void

dcss_mkname(char *name, char *dcss_name)

{

        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);

}

/*

 * 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(!mutex_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.

 */

static inline int

dcss_diag (__u8 func, void *parameter,

           unsigned long *ret1, unsigned long *ret2)

{

        unsigned long rx, ry;

        int rc;

        rx = (unsigned long) parameter;

        ry = (unsigned long) func;

        asm volatile(

#ifdef CONFIG_64BIT

                "       sam31\n"

                "       diag    %0,%1,0x64\n"

                "       sam64\n"

#else

                "       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;

}

static inline int

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_type (struct dcss_segment *seg)

{

        struct qin64  *qin = kmalloc (sizeof(struct qin64), GFP_DMA);

        struct qout64 *qout = kmalloc (sizeof(struct qout64), GFP_DMA);

        int diag_cc, rc, i;

        unsigned long dummy, vmrc;

        if ((qin == NULL) || (qout == NULL)) {

                rc = -ENOMEM;

                goto out_free;

        }

        /* initialize diag input parameters */

        qin->qopcode = DCSS_FINDSEGA;

        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) {

                PRINT_WARN ("segment_type: diag returned error %ld\n", vmrc);

                rc = dcss_diag_translate_rc (vmrc);

                goto out_free;

        }

        if (qout->segcnt > 6) {

                rc = -ENOTSUPP;

                goto out_free;

        }

        if (qout->segcnt == 1) {

                seg->vm_segtype = qout->range[0].start & 0xff;

        } else {

                /* multi-part segment. only one type supported here:

                    - all parts are contiguous

                    - all parts are either EW or EN type

                    - maximum 6 parts allowed */

                unsigned long start = qout->segstart >> PAGE_SHIFT;

                for (i=0; i<qout->segcnt; i++) {

                        if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&

                            ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {

                                rc = -ENOTSUPP;

                                goto out_free;

                        }

                        if (start != qout->range[i].start >> PAGE_SHIFT) {

                                rc = -ENOTSUPP;

                                goto out_free;

                        }

                        start = (qout->range[i].end >> PAGE_SHIFT) + 1;

                }

                seg->vm_segtype = SEG_TYPE_EWEN;

        }

        /* analyze diag output and update seg */

        seg->start_addr = qout->segstart;

        seg->end = qout->segend;

        memcpy (seg->range, qout->range, 6*sizeof(struct qrange));

        seg->segcnt = qout->segcnt;

        rc = 0;

 out_free:

        kfree(qin);

        kfree(qout);

        return rc;

}

/*

 * 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_type (char* name)

{

        int rc;

        struct dcss_segment seg;

        if (!MACHINE_IS_VM)

                return -ENOSYS;

        dcss_mkname(name, seg.dcss_name);

        rc = query_segment_type (&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_type (seg);

        if (rc < 0)

                goto out_free;

        rc = add_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);

        switch (rc) {

        case 0:

                break;

        case -ENOSPC:

                PRINT_WARN("segment_load: not loading segment %s - overlaps "

                           "storage/segment\n", name);

                goto out_free;

        case -ERANGE:

                PRINT_WARN("segment_load: not loading segment %s - exceeds "

                           "kernel mapping range\n", name);

                goto out_free;

        default:

                PRINT_WARN("segment_load: not loading segment %s (rc: %d)\n",

                           name, rc);

                goto out_free;

        }

        seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);

        if (seg->res == NULL) {

                rc = -ENOMEM;

                goto out_shared;

        }

        seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;

        seg->res->start = seg->start_addr;

        seg->res->end = seg->end;

        memcpy(&seg->res_name, seg->dcss_name, 8);

        EBCASC(seg->res_name, 8);

        seg->res_name[8] = '\0';

        strncat(seg->res_name, " (DCSS)", 7);

        seg->res->name = seg->res_name;

        rc = seg->vm_segtype;

        if (rc == SEG_TYPE_SC ||

            ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))

                seg->res->flags |= IORESOURCE_READONLY;

        if (request_resource(&iomem_resource, seg->res)) {

                rc = -EBUSY;

                kfree(seg->res);

                goto out_shared;

        }

        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_resource;

        }

        seg->do_nonshared = do_nonshared;

        atomic_set(&seg->ref_count, 1);

        list_add(&seg->list, &dcss_list);

        *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_resource:

        release_resource(seg->res);

        kfree(seg->res);

 out_shared:

        remove_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);

 out_free:

        kfree(seg);

 out:

        return rc;

}

/*

 * 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)

 * -ERANGE  : segment cannot be used (exceeds kernel mapping range)

 * -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 do_nonshared, unsigned long *addr,

                unsigned long *end)

{

        struct dcss_segment *seg;

        int rc;

        if (!MACHINE_IS_VM)

                return -ENOSYS;

        mutex_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;

                }

        }

        mutex_unlock(&dcss_lock);

        return rc;

}

/*

 * this function modifies the shared state of a DCSS segment. note that

 * 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

 * return values:

 * -EIO     : could not perform load diagnose (segment gone!)

 * -ENOENT  : no such segment (segment gone!)

 * -EAGAIN  : segment is in use by other exploiters, try later

 * -EINVAL  : no segment with the given name is currently loaded - name invalid

 * -EBUSY   : segment can temporarily not be used (overlaps with dcss)

 * 0        : operation succeeded

 */

int

segment_modify_shared (char *name, int do_nonshared)

{

        struct dcss_segment *seg;

        unsigned long dummy;

        int dcss_command, rc, diag_cc;

        mutex_lock(&dcss_lock);

        seg = segment_by_name (name);

        if (seg == NULL) {

                rc = -EINVAL;

                goto out_unlock;

        }

        if (do_nonshared == seg->do_nonshared) {

                PRINT_INFO ("segment_modify_shared: not reloading segment %s"

                                " - already in requested mode\n",name);

                rc = 0;

                goto out_unlock;

        }

        if (atomic_read (&seg->ref_count) != 1) {

                PRINT_WARN ("segment_modify_shared: not reloading segment %s - "

                                "segment is in use by other driver(s)\n",name);

                rc = -EAGAIN;

                goto out_unlock;

        }

        release_resource(seg->res);

        if (do_nonshared) {

                dcss_command = DCSS_LOADNSR;

                seg->res->flags &= ~IORESOURCE_READONLY;

        } else {

                dcss_command = DCSS_LOADNOLY;

                if (seg->vm_segtype == SEG_TYPE_SR ||

                    seg->vm_segtype == SEG_TYPE_ER)

                        seg->res->flags |= IORESOURCE_READONLY;

        }

        if (request_resource(&iomem_resource, seg->res)) {

                PRINT_WARN("segment_modify_shared: could not reload segment %s"

                           " - overlapping resources\n", name);

                rc = -EBUSY;

                kfree(seg->res);

                goto out_del;

        }

        dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);

        diag_cc = dcss_diag(dcss_command, seg->dcss_name,

                        &seg->start_addr, &seg->end);

        if (diag_cc > 1) {

                PRINT_WARN ("segment_modify_shared: could not reload segment %s"

                                " - diag returned error (%ld)\n",name,seg->end);

                rc = dcss_diag_translate_rc (seg->end);

                goto out_del;

        }

        seg->do_nonshared = do_nonshared;

        rc = 0;

        goto out_unlock;

 out_del:

        remove_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);

        list_del(&seg->list);

        dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);

        kfree(seg);

 out_unlock:

        mutex_unlock(&dcss_lock);

        return rc;

}

/*

 * Decrease the use count of a DCSS segment and remove

 * it from the address space if nobody is using it

 * any longer.

 */

void

segment_unload(char *name)

{

        unsigned long dummy;

        struct dcss_segment *seg;

        if (!MACHINE_IS_VM)

                return;

        mutex_lock(&dcss_lock);

        seg = segment_by_name (name);

        if (seg == NULL) {

                PRINT_ERR ("could not find segment %s in segment_unload, "

                                "please report to linux390@de.ibm.com\n",name);

                goto out_unlock;

        }

        if (atomic_dec_return(&seg->ref_count) != 0)

                goto out_unlock;

        release_resource(seg->res);

        kfree(seg->res);

        remove_shared_memory(seg->start_addr, seg->end - seg->start_addr + 1);

        list_del(&seg->list);

        dcss_diag(DCSS_PURGESEG, seg->dcss_name, &dummy, &dummy);

        kfree(seg);

out_unlock:

        mutex_unlock(&dcss_lock);

}

/*

 * save segment content permanently

 */

void

segment_save(char *name)

{

        struct dcss_segment *seg;

        int startpfn = 0;

        int endpfn = 0;

        char cmd1[160];

        char cmd2[80];

        int i, response;

        if (!MACHINE_IS_VM)

                return;

        mutex_lock(&dcss_lock);

        seg = segment_by_name (name);

        if (seg == NULL) {

                PRINT_ERR("could not find segment %s in segment_save, please "

                          "report to linux390@de.ibm.com\n", name);

                goto out;

        }

        startpfn = seg->start_addr >> PAGE_SHIFT;

        endpfn = (seg->end) >> PAGE_SHIFT;

        sprintf(cmd1, "DEFSEG %s", name);

        for (i=0; i<seg->segcnt; i++) {

                sprintf(cmd1+strlen(cmd1), " %X-%X %s",

                        seg->range[i].start >> PAGE_SHIFT,

                        seg->range[i].end >> PAGE_SHIFT,

                        segtype_string[seg->range[i].start & 0xff]);

        }

        sprintf(cmd2, "SAVESEG %s", name);

        response = 0;

        cpcmd(cmd1, NULL, 0, &response);

        if (response) {

                PRINT_ERR("segment_save: DEFSEG failed with response code %i\n",

                          response);

                goto out;

        }

        cpcmd(cmd2, NULL, 0, &response);

        if (response) {

                PRINT_ERR("segment_save: SAVESEG failed with response code %i\n",

                          response);

                goto out;

        }

out:

        mutex_unlock(&dcss_lock);

}

EXPORT_SYMBOL(segment_load);

EXPORT_SYMBOL(segment_unload);

EXPORT_SYMBOL(segment_save);

EXPORT_SYMBOL(segment_type);

EXPORT_SYMBOL(segment_modify_shared);