]> git.saurik.com Git - apple/xnu.git/blobdiff - iokit/bsddev/IOKitBSDInit.cpp
xnu-6153.61.1.tar.gz
[apple/xnu.git] / iokit / bsddev / IOKitBSDInit.cpp
index f68eebd1e7e951ea1be46616b3238fd191620090..11514d895466efd57e6be8f54575246b21fff679 100644 (file)
@@ -2,7 +2,7 @@
  * Copyright (c) 1998-2011 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 
+ *
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
- * 
+ *
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
+ *
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
@@ -22,7 +22,7 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
- * 
+ *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 #include <IOKit/IOBSD.h>
@@ -35,9 +35,9 @@
 #include <IOKit/IOUserClient.h>
 
 extern "C" {
-
 #include <pexpert/pexpert.h>
 #include <kern/clock.h>
+#include <mach/machine.h>
 #include <uuid/uuid.h>
 #include <sys/vnode_internal.h>
 #include <sys/mount.h>
@@ -49,38 +49,22 @@ extern "C" {
 #define ROOTDEVICETIMEOUT       60
 #endif
 
-int panic_on_exception_triage = 0;
-
 extern dev_t mdevadd(int devid, uint64_t base, unsigned int size, int phys);
 extern dev_t mdevlookup(int devid);
 extern void mdevremoveall(void);
 extern int mdevgetrange(int devid, uint64_t *base, uint64_t *size);
 extern void di_root_ramfile(IORegistryEntry * entry);
 
+#define ROUNDUP(a, b) (((a) + ((b) - 1)) & (~((b) - 1)))
 
-#if CONFIG_EMBEDDED
-#define IOPOLLED_COREFILE      (CONFIG_KDP_INTERACTIVE_DEBUGGING)
-#define kIOCoreDumpPath        "/private/var/vm/kernelcore"
-#define kIOCoreDumpSize                350ULL*1024ULL*1024ULL
-// leave free space on volume:
-#define kIOCoreDumpFreeSize    350ULL*1024ULL*1024ULL
-#elif DEVELOPMENT
-#define IOPOLLED_COREFILE      1
-// no sizing
-#define kIOCoreDumpSize                0ULL
-#define kIOCoreDumpFreeSize    0ULL
+#define IOPOLLED_COREFILE       (CONFIG_KDP_INTERACTIVE_DEBUGGING)
+
+#if defined(XNU_TARGET_OS_BRIDGE)
+#define kIOCoreDumpPath         "/private/var/internal/kernelcore"
 #else
-#define IOPOLLED_COREFILE      0
+#define kIOCoreDumpPath         "/private/var/vm/kernelcore"
 #endif
 
-
-#if IOPOLLED_COREFILE
-static bool 
-NewKernelCoreMedia(void * target, void * refCon,
-                  IOService * newService,
-                  IONotifier * notifier);
-#endif /* IOPOLLED_COREFILE */
-
 #if CONFIG_KDP_INTERACTIVE_DEBUGGING
 /*
  * Touched by IOFindBSDRoot() if a RAMDisk is used for the root device.
@@ -89,609 +73,668 @@ extern uint64_t kdp_core_ramdisk_addr;
 extern uint64_t kdp_core_ramdisk_size;
 #endif
 
+#if IOPOLLED_COREFILE
+static void IOOpenPolledCoreFile(thread_call_param_t __unused, thread_call_param_t corefilename);
+
+thread_call_t corefile_open_call = NULL;
+#endif
+
 kern_return_t
 IOKitBSDInit( void )
 {
-    IOService::publishResource("IOBSD");
+       IOService::publishResource("IOBSD");
 
-    return( kIOReturnSuccess );
+#if IOPOLLED_COREFILE
+       corefile_open_call = thread_call_allocate_with_options(IOOpenPolledCoreFile, NULL, THREAD_CALL_PRIORITY_KERNEL, THREAD_CALL_OPTIONS_ONCE);
+#endif
+
+       return kIOReturnSuccess;
 }
 
 void
 IOServicePublishResource( const char * property, boolean_t value )
 {
-    if ( value)
-        IOService::publishResource( property, kOSBooleanTrue );
-    else
-        IOService::getResourceService()->removeProperty( property );
+       if (value) {
+               IOService::publishResource( property, kOSBooleanTrue );
+       } else {
+               IOService::getResourceService()->removeProperty( property );
+       }
 }
 
 boolean_t
 IOServiceWaitForMatchingResource( const char * property, uint64_t timeout )
 {
-    OSDictionary *     dict = 0;
-    IOService *         match = 0;
-    boolean_t          found = false;
-    
-    do {
-        
-        dict = IOService::resourceMatching( property );
-        if( !dict)
-            continue;
-        match = IOService::waitForMatchingService( dict, timeout );
-        if ( match)
-            found = true;
-        
-    } while( false );
-    
-    if( dict)
-        dict->release();
-    if( match)
-        match->release();
-    
-    return( found );
+       OSDictionary *      dict = NULL;
+       IOService *         match = NULL;
+       boolean_t           found = false;
+
+       do {
+               dict = IOService::resourceMatching( property );
+               if (!dict) {
+                       continue;
+               }
+               match = IOService::waitForMatchingService( dict, timeout );
+               if (match) {
+                       found = true;
+               }
+       } while (false);
+
+       if (dict) {
+               dict->release();
+       }
+       if (match) {
+               match->release();
+       }
+
+       return found;
 }
 
 boolean_t
 IOCatalogueMatchingDriversPresent( const char * property )
 {
-    OSDictionary *     dict = 0;
-    OSOrderedSet *     set = 0;
-    SInt32             generationCount = 0;
-    boolean_t          found = false;
-    
-    do {
-        
-        dict = OSDictionary::withCapacity(1);
-        if( !dict)
-            continue;
-        dict->setObject( property, kOSBooleanTrue );
-        set = gIOCatalogue->findDrivers( dict, &generationCount );
-        if ( set && (set->getCount() > 0))
-            found = true;
-        
-    } while( false );
-    
-    if( dict)
-        dict->release();
-    if( set)
-        set->release();
-    
-    return( found );
-}
+       OSDictionary *      dict = NULL;
+       OSOrderedSet *      set = NULL;
+       SInt32              generationCount = 0;
+       boolean_t           found = false;
+
+       do {
+               dict = OSDictionary::withCapacity(1);
+               if (!dict) {
+                       continue;
+               }
+               dict->setObject( property, kOSBooleanTrue );
+               set = gIOCatalogue->findDrivers( dict, &generationCount );
+               if (set && (set->getCount() > 0)) {
+                       found = true;
+               }
+       } while (false);
 
-OSDictionary * IOBSDNameMatching( const char * name )
-{
-    OSDictionary *     dict;
-    const OSSymbol *   str = 0;
+       if (dict) {
+               dict->release();
+       }
+       if (set) {
+               set->release();
+       }
 
-    do {
+       return found;
+}
 
-       dict = IOService::serviceMatching( gIOServiceKey );
-       if( !dict)
-           continue;
-        str = OSSymbol::withCString( name );
-       if( !str)
-           continue;
-        dict->setObject( kIOBSDNameKey, (OSObject *) str );
-        str->release();
+OSDictionary *
+IOBSDNameMatching( const char * name )
+{
+       OSDictionary *      dict;
+       const OSSymbol *    str = NULL;
 
-        return( dict );
+       do {
+               dict = IOService::serviceMatching( gIOServiceKey );
+               if (!dict) {
+                       continue;
+               }
+               str = OSSymbol::withCString( name );
+               if (!str) {
+                       continue;
+               }
+               dict->setObject( kIOBSDNameKey, (OSObject *) str );
+               str->release();
 
-    } while( false );
+               return dict;
+       } while (false);
 
-    if( dict)
-       dict->release();
-    if( str)
-       str->release();
+       if (dict) {
+               dict->release();
+       }
+       if (str) {
+               str->release();
+       }
 
-    return( 0 );
+       return NULL;
 }
 
-OSDictionary * IOUUIDMatching( void )
+OSDictionary *
+IOUUIDMatching( void )
 {
-    return IOService::resourceMatching( "boot-uuid-media" );
+       return IOService::resourceMatching( "boot-uuid-media" );
 }
 
-OSDictionary * IONetworkNamePrefixMatching( const char * prefix )
+OSDictionary *
+IONetworkNamePrefixMatching( const char * prefix )
 {
-    OSDictionary *      matching;
-    OSDictionary *   propDict = 0;
-    const OSSymbol * str      = 0;
+       OSDictionary *       matching;
+       OSDictionary *   propDict = NULL;
+       const OSSymbol * str      = NULL;
        char networkType[128];
-       
-    do {
-        matching = IOService::serviceMatching( "IONetworkInterface" );
-        if ( matching == 0 )
-            continue;
 
-        propDict = OSDictionary::withCapacity(1);
-        if ( propDict == 0 )
-            continue;
+       do {
+               matching = IOService::serviceMatching( "IONetworkInterface" );
+               if (matching == NULL) {
+                       continue;
+               }
+
+               propDict = OSDictionary::withCapacity(1);
+               if (propDict == NULL) {
+                       continue;
+               }
 
-        str = OSSymbol::withCString( prefix );
-        if ( str == 0 )
-            continue;
+               str = OSSymbol::withCString( prefix );
+               if (str == NULL) {
+                       continue;
+               }
 
-        propDict->setObject( "IOInterfaceNamePrefix", (OSObject *) str );
-        str->release();
-        str = 0;
+               propDict->setObject( "IOInterfaceNamePrefix", (OSObject *) str );
+               str->release();
+               str = NULL;
 
                // see if we're contrained to netroot off of specific network type
-               if(PE_parse_boot_argn( "network-type", networkType, 128 ))
-               {
+               if (PE_parse_boot_argn( "network-type", networkType, 128 )) {
                        str = OSSymbol::withCString( networkType );
-                       if(str)
-                       {
+                       if (str) {
                                propDict->setObject( "IONetworkRootType", str);
                                str->release();
-                               str = 0;
+                               str = NULL;
                        }
                }
 
-        if ( matching->setObject( gIOPropertyMatchKey,
-                                  (OSObject *) propDict ) != true )
-            continue;
-
-        propDict->release();
-        propDict = 0;
+               if (matching->setObject( gIOPropertyMatchKey,
+                   (OSObject *) propDict ) != true) {
+                       continue;
+               }
 
-        return( matching );
+               propDict->release();
+               propDict = NULL;
 
-    } while ( false );
+               return matching;
+       } while (false);
 
-    if ( matching ) matching->release();
-    if ( propDict ) propDict->release();
-    if ( str      ) str->release();
+       if (matching) {
+               matching->release();
+       }
+       if (propDict) {
+               propDict->release();
+       }
+       if (str) {
+               str->release();
+       }
 
-    return( 0 );
+       return NULL;
 }
 
-static bool IORegisterNetworkInterface( IOService * netif )
+static bool
+IORegisterNetworkInterface( IOService * netif )
 {
-    // A network interface is typically named and registered
-    // with BSD after receiving a request from a user space
-    // "namer". However, for cases when the system needs to
-    // root from the network, this registration task must be
-    // done inside the kernel and completed before the root
-    // device is handed to BSD.
-
-    IOService *    stack;
-    OSNumber *     zero    = 0;
-    OSString *     path    = 0;
-    OSDictionary * dict    = 0;
-    char *         pathBuf = 0;
-    int            len;
-    enum { kMaxPathLen = 512 };
-
-    do {
-        stack = IOService::waitForService(
-                IOService::serviceMatching("IONetworkStack") );
-        if ( stack == 0 ) break;
-
-        dict = OSDictionary::withCapacity(3);
-        if ( dict == 0 ) break;
-
-        zero = OSNumber::withNumber((UInt64) 0, 32);
-        if ( zero == 0 ) break;
-
-        pathBuf = (char *) IOMalloc( kMaxPathLen );
-        if ( pathBuf == 0 ) break;
-
-        len = kMaxPathLen;
-        if ( netif->getPath( pathBuf, &len, gIOServicePlane )
-             == false ) break;
-
-        path = OSString::withCStringNoCopy( pathBuf );
-        if ( path == 0 ) break;
-
-        dict->setObject( "IOInterfaceUnit", zero );
-        dict->setObject( kIOPathMatchKey,   path );
-
-        stack->setProperties( dict );
-    }
-    while ( false );
-
-    if ( zero ) zero->release();
-    if ( path ) path->release();
-    if ( dict ) dict->release();
-    if ( pathBuf ) IOFree(pathBuf, kMaxPathLen);
-
-       return ( netif->getProperty( kIOBSDNameKey ) != 0 );
-}
+       // A network interface is typically named and registered
+       // with BSD after receiving a request from a user space
+       // "namer". However, for cases when the system needs to
+       // root from the network, this registration task must be
+       // done inside the kernel and completed before the root
+       // device is handed to BSD.
+
+       IOService *    stack;
+       OSNumber *     zero    = NULL;
+       OSString *     path    = NULL;
+       OSDictionary * dict    = NULL;
+       char *         pathBuf = NULL;
+       int            len;
+       enum { kMaxPathLen = 512 };
+
+       do {
+               stack = IOService::waitForService(
+                       IOService::serviceMatching("IONetworkStack"));
+               if (stack == NULL) {
+                       break;
+               }
 
-OSDictionary * IOOFPathMatching( const char * path, char * buf, int maxLen )
-{
-    OSDictionary *     matching = NULL;
-    OSString *         str;
-    char *             comp;
-    int                        len;
+               dict = OSDictionary::withCapacity(3);
+               if (dict == NULL) {
+                       break;
+               }
 
-    do {
+               zero = OSNumber::withNumber((UInt64) 0, 32);
+               if (zero == NULL) {
+                       break;
+               }
 
-       len = strlen( kIODeviceTreePlane ":" );
-       maxLen -= len;
-       if( maxLen <= 0)
-           continue;
+               pathBuf = (char *) IOMalloc( kMaxPathLen );
+               if (pathBuf == NULL) {
+                       break;
+               }
 
-       strlcpy( buf, kIODeviceTreePlane ":", len + 1 );
-       comp = buf + len;
+               len = kMaxPathLen;
+               if (netif->getPath( pathBuf, &len, gIOServicePlane )
+                   == false) {
+                       break;
+               }
 
-       len = strlen( path );
-       maxLen -= len;
-       if( maxLen <= 0)
-           continue;
-       strlcpy( comp, path, len + 1 );
+               path = OSString::withCStringNoCopy( pathBuf );
+               if (path == NULL) {
+                       break;
+               }
 
-       matching = OSDictionary::withCapacity( 1 );
-       if( !matching)
-           continue;
+               dict->setObject( "IOInterfaceUnit", zero );
+               dict->setObject( kIOPathMatchKey, path );
 
-       str = OSString::withCString( buf );
-       if( !str)
-           continue;
-        matching->setObject( kIOPathMatchKey, str );
-       str->release();
+               stack->setProperties( dict );
+       }while (false);
 
-       return( matching );
+       if (zero) {
+               zero->release();
+       }
+       if (path) {
+               path->release();
+       }
+       if (dict) {
+               dict->release();
+       }
+       if (pathBuf) {
+               IOFree(pathBuf, kMaxPathLen);
+       }
+
+       return netif->getProperty( kIOBSDNameKey ) != NULL;
+}
 
-    } while( false );
+OSDictionary *
+IOOFPathMatching( const char * path, char * buf, int maxLen )
+{
+       OSDictionary *      matching = NULL;
+       OSString *          str;
+       char *              comp;
+       int                 len;
+
+       do {
+               len = strlen( kIODeviceTreePlane ":" );
+               maxLen -= len;
+               if (maxLen <= 0) {
+                       continue;
+               }
 
-    if( matching)
-        matching->release();
+               strlcpy( buf, kIODeviceTreePlane ":", len + 1 );
+               comp = buf + len;
 
-    return( 0 );
+               len = strlen( path );
+               maxLen -= len;
+               if (maxLen <= 0) {
+                       continue;
+               }
+               strlcpy( comp, path, len + 1 );
+
+               matching = OSDictionary::withCapacity( 1 );
+               if (!matching) {
+                       continue;
+               }
+
+               str = OSString::withCString( buf );
+               if (!str) {
+                       continue;
+               }
+               matching->setObject( kIOPathMatchKey, str );
+               str->release();
+
+               return matching;
+       } while (false);
+
+       if (matching) {
+               matching->release();
+       }
+
+       return NULL;
 }
 
 static int didRam = 0;
 enum { kMaxPathBuf = 512, kMaxBootVar = 128 };
 
-kern_return_t IOFindBSDRoot( char * rootName, unsigned int rootNameSize,
-                               dev_t * root, u_int32_t * oflags )
+kern_return_t
+IOFindBSDRoot( char * rootName, unsigned int rootNameSize,
+    dev_t * root, u_int32_t * oflags )
 {
-    mach_timespec_t    t;
-    IOService *                service;
-    IORegistryEntry *  regEntry;
-    OSDictionary *     matching = 0;
-    OSString *         iostr;
-    OSNumber *         off;
-    OSData *           data = 0;
-
-    UInt32             flags = 0;
-    int                        mnr, mjr;
-    const char *        mediaProperty = 0;
-    char *             rdBootVar;
-    char *             str;
-    const char *       look = 0;
-    int                        len;
-    bool               debugInfoPrintedOnce = false;
-    const char *       uuidStr = NULL;
-
-    static int         mountAttempts = 0;
-                               
-    int xchar, dchar;
-
-    // stall here for anyone matching on the IOBSD resource to finish (filesystems)
-    matching = IOService::serviceMatching(gIOResourcesKey);
-    assert(matching);
-    matching->setObject(gIOResourceMatchedKey, gIOBSDKey);
+       mach_timespec_t     t;
+       IOService *         service;
+       IORegistryEntry *   regEntry;
+       OSDictionary *      matching = NULL;
+       OSString *          iostr;
+       OSNumber *          off;
+       OSData *            data = NULL;
+
+       UInt32              flags = 0;
+       int                 mnr, mjr;
+       const char *        mediaProperty = NULL;
+       char *              rdBootVar;
+       char *              str;
+       const char *        look = NULL;
+       int                 len;
+       bool                debugInfoPrintedOnce = false;
+       bool                needNetworkKexts = false;
+       const char *        uuidStr = NULL;
+
+       static int          mountAttempts = 0;
+
+       int xchar, dchar;
+
+       // stall here for anyone matching on the IOBSD resource to finish (filesystems)
+       matching = IOService::serviceMatching(gIOResourcesKey);
+       assert(matching);
+       matching->setObject(gIOResourceMatchedKey, gIOBSDKey);
 
        if ((service = IOService::waitForMatchingService(matching, 30ULL * kSecondScale))) {
                service->release();
        } else {
                IOLog("!BSD\n");
        }
-    matching->release();
+       matching->release();
        matching = NULL;
 
-    if( mountAttempts++)
-    {
-        IOLog("mount(%d) failed\n", mountAttempts);
-       IOSleep( 5 * 1000 );
-    }
-
-    str = (char *) IOMalloc( kMaxPathBuf + kMaxBootVar );
-    if( !str)
-       return( kIOReturnNoMemory );
-    rdBootVar = str + kMaxPathBuf;
-
-    if (!PE_parse_boot_argn("rd", rdBootVar, kMaxBootVar )
-     && !PE_parse_boot_argn("rootdev", rdBootVar, kMaxBootVar ))
-       rdBootVar[0] = 0;
-
-    do {
-       if( (regEntry = IORegistryEntry::fromPath( "/chosen", gIODTPlane ))) {
-           di_root_ramfile(regEntry);
-            data = OSDynamicCast(OSData, regEntry->getProperty( "root-matching" ));
-            if (data) {
-               matching = OSDynamicCast(OSDictionary, OSUnserializeXML((char *)data->getBytesNoCopy()));
-                if (matching) {
-                    continue;
-                }
-            }
-
-           data = (OSData *) regEntry->getProperty( "boot-uuid" );
-           if( data) {
-               uuidStr = (const char*)data->getBytesNoCopy();
-               OSString *uuidString = OSString::withCString( uuidStr );
-
-               // match the boot-args boot-uuid processing below
-               if( uuidString) {
-                   IOLog("rooting via boot-uuid from /chosen: %s\n", uuidStr);
-                   IOService::publishResource( "boot-uuid", uuidString );
-                   uuidString->release();
-                   matching = IOUUIDMatching();
-                   mediaProperty = "boot-uuid-media";
-                   regEntry->release();
-                   continue;
-               } else {
-                   uuidStr = NULL;
-               }
-           }
-           regEntry->release();
+       if (mountAttempts++) {
+               IOLog("mount(%d) failed\n", mountAttempts);
+               IOSleep( 5 * 1000 );
        }
-    } while( false );
+
+       str = (char *) IOMalloc( kMaxPathBuf + kMaxBootVar );
+       if (!str) {
+               return kIOReturnNoMemory;
+       }
+       rdBootVar = str + kMaxPathBuf;
+
+       if (!PE_parse_boot_argn("rd", rdBootVar, kMaxBootVar )
+           && !PE_parse_boot_argn("rootdev", rdBootVar, kMaxBootVar )) {
+               rdBootVar[0] = 0;
+       }
+
+       do {
+               if ((regEntry = IORegistryEntry::fromPath( "/chosen", gIODTPlane ))) {
+                       di_root_ramfile(regEntry);
+                       data = OSDynamicCast(OSData, regEntry->getProperty( "root-matching" ));
+                       if (data) {
+                               matching = OSDynamicCast(OSDictionary, OSUnserializeXML((char *)data->getBytesNoCopy()));
+                               if (matching) {
+                                       continue;
+                               }
+                       }
+
+                       data = (OSData *) regEntry->getProperty( "boot-uuid" );
+                       if (data) {
+                               uuidStr = (const char*)data->getBytesNoCopy();
+                               OSString *uuidString = OSString::withCString( uuidStr );
+
+                               // match the boot-args boot-uuid processing below
+                               if (uuidString) {
+                                       IOLog("rooting via boot-uuid from /chosen: %s\n", uuidStr);
+                                       IOService::publishResource( "boot-uuid", uuidString );
+                                       uuidString->release();
+                                       matching = IOUUIDMatching();
+                                       mediaProperty = "boot-uuid-media";
+                                       regEntry->release();
+                                       continue;
+                               } else {
+                                       uuidStr = NULL;
+                               }
+                       }
+                       regEntry->release();
+               }
+       } while (false);
 
 //
 //     See if we have a RAMDisk property in /chosen/memory-map.  If so, make it into a device.
-//     It will become /dev/mdx, where x is 0-f. 
+//     It will become /dev/mdx, where x is 0-f.
 //
 
-       if(!didRam) {                                                                                           /* Have we already build this ram disk? */
-               didRam = 1;                                                                                             /* Remember we did this */
-               if((regEntry = IORegistryEntry::fromPath( "/chosen/memory-map", gIODTPlane ))) {        /* Find the map node */
-                       data = (OSData *)regEntry->getProperty("RAMDisk");      /* Find the ram disk, if there */
-                       if(data) {                                                                                      /* We found one */
+       if (!didRam) {                                                                                           /* Have we already build this ram disk? */
+               didRam = 1;                                                                                             /* Remember we did this */
+               if ((regEntry = IORegistryEntry::fromPath( "/chosen/memory-map", gIODTPlane ))) {        /* Find the map node */
+                       data = (OSData *)regEntry->getProperty("RAMDisk");      /* Find the ram disk, if there */
+                       if (data) {                                                                                      /* We found one */
                                uintptr_t *ramdParms;
-                               ramdParms = (uintptr_t *)data->getBytesNoCopy();        /* Point to the ram disk base and size */
-                               (void)mdevadd(-1, ml_static_ptovirt(ramdParms[0]) >> 12, ramdParms[1] >> 12, 0);        /* Initialize it and pass back the device number */
+                               ramdParms = (uintptr_t *)data->getBytesNoCopy();        /* Point to the ram disk base and size */
+                               (void)mdevadd(-1, ml_static_ptovirt(ramdParms[0]) >> 12, ramdParms[1] >> 12, 0);        /* Initialize it and pass back the device number */
                        }
-                       regEntry->release();                                                            /* Toss the entry */
+                       regEntry->release();                                                            /* Toss the entry */
                }
        }
-       
+
 //
 //     Now check if we are trying to root on a memory device
 //
 
-       if((rdBootVar[0] == 'm') && (rdBootVar[1] == 'd') && (rdBootVar[3] == 0)) {
-               dchar = xchar = rdBootVar[2];                                                   /* Get the actual device */
-               if((xchar >= '0') && (xchar <= '9')) xchar = xchar - '0';       /* If digit, convert */
-               else {
-                       xchar = xchar & ~' ';                                                           /* Fold to upper case */
-                       if((xchar >= 'A') && (xchar <= 'F')) {                          /* Is this a valid digit? */
-                               xchar = (xchar & 0xF) + 9;                                              /* Convert the hex digit */
-                               dchar = dchar | ' ';                                                    /* Fold to lower case */
+       if ((rdBootVar[0] == 'm') && (rdBootVar[1] == 'd') && (rdBootVar[3] == 0)) {
+               dchar = xchar = rdBootVar[2];                                                   /* Get the actual device */
+               if ((xchar >= '0') && (xchar <= '9')) {
+                       xchar = xchar - '0';                                    /* If digit, convert */
+               } else {
+                       xchar = xchar & ~' ';                                                           /* Fold to upper case */
+                       if ((xchar >= 'A') && (xchar <= 'F')) {                          /* Is this a valid digit? */
+                               xchar = (xchar & 0xF) + 9;                                              /* Convert the hex digit */
+                               dchar = dchar | ' ';                                                    /* Fold to lower case */
+                       } else {
+                               xchar = -1;                                                                     /* Show bogus */
                        }
-                       else xchar = -1;                                                                        /* Show bogus */
-               }
-               if(xchar >= 0) {                                                                                /* Do we have a valid memory device name? */
-                       *root = mdevlookup(xchar);                                                      /* Find the device number */
-                       if(*root >= 0) {                                                                        /* Did we find one? */
-                               rootName[0] = 'm';                                                              /* Build root name */
-                               rootName[1] = 'd';                                                              /* Build root name */
-                               rootName[2] = dchar;                                                    /* Build root name */
-                               rootName[3] = 0;                                                                /* Build root name */
+               }
+               if (xchar >= 0) {                                                                                /* Do we have a valid memory device name? */
+                       *root = mdevlookup(xchar);                                                      /* Find the device number */
+                       if (*root >= 0) {                                                                        /* Did we find one? */
+                               rootName[0] = 'm';                                                              /* Build root name */
+                               rootName[1] = 'd';                                                              /* Build root name */
+                               rootName[2] = dchar;                                                    /* Build root name */
+                               rootName[3] = 0;                                                                /* Build root name */
                                IOLog("BSD root: %s, major %d, minor %d\n", rootName, major(*root), minor(*root));
-                               *oflags = 0;                                                                    /* Show that this is not network */
+                               *oflags = 0;                                                                    /* Show that this is not network */
 
 #if CONFIG_KDP_INTERACTIVE_DEBUGGING
-                /* retrieve final ramdisk range and initialize KDP variables */
-                if (mdevgetrange(xchar, &kdp_core_ramdisk_addr, &kdp_core_ramdisk_size) != 0) {
-                    IOLog("Unable to retrieve range for root memory device %d\n", xchar);
-                    kdp_core_ramdisk_addr = 0;
-                    kdp_core_ramdisk_size = 0;
-                }
+                               /* retrieve final ramdisk range and initialize KDP variables */
+                               if (mdevgetrange(xchar, &kdp_core_ramdisk_addr, &kdp_core_ramdisk_size) != 0) {
+                                       IOLog("Unable to retrieve range for root memory device %d\n", xchar);
+                                       kdp_core_ramdisk_addr = 0;
+                                       kdp_core_ramdisk_size = 0;
+                               }
 #endif
 
-                               goto iofrootx;                                                                  /* Join common exit... */
+                               goto iofrootx;                                                                  /* Join common exit... */
                        }
-                       panic("IOFindBSDRoot: specified root memory device, %s, has not been configured\n", rdBootVar); /* Not there */
-               }
-       }
-
-      if( (!matching) && rdBootVar[0] ) {
-       // by BSD name
-       look = rdBootVar;
-       if( look[0] == '*')
-           look++;
-    
-       if ( strncmp( look, "en", strlen( "en" )) == 0 ) {
-           matching = IONetworkNamePrefixMatching( "en" );
-       } else if ( strncmp( look, "uuid", strlen( "uuid" )) == 0 ) {
-            char *uuid;
-            OSString *uuidString;
-
-            uuid = (char *)IOMalloc( kMaxBootVar );
-                  
-            if ( uuid ) {
-                if (!PE_parse_boot_argn( "boot-uuid", uuid, kMaxBootVar )) {
-                    panic( "rd=uuid but no boot-uuid=<value> specified" ); 
-                } 
-                uuidString = OSString::withCString( uuid );
-                if ( uuidString ) {
-                    IOService::publishResource( "boot-uuid", uuidString );
-                    uuidString->release();
-                    IOLog( "\nWaiting for boot volume with UUID %s\n", uuid );
-                    matching = IOUUIDMatching();
-                    mediaProperty = "boot-uuid-media";
-                }
-                IOFree( uuid, kMaxBootVar );
-            }
+                       panic("IOFindBSDRoot: specified root memory device, %s, has not been configured\n", rdBootVar); /* Not there */
+               }
+       }
+
+       if ((!matching) && rdBootVar[0]) {
+               // by BSD name
+               look = rdBootVar;
+               if (look[0] == '*') {
+                       look++;
+               }
+
+               if (strncmp( look, "en", strlen( "en" )) == 0) {
+                       matching = IONetworkNamePrefixMatching( "en" );
+                       needNetworkKexts = true;
+               } else if (strncmp( look, "uuid", strlen( "uuid" )) == 0) {
+                       char *uuid;
+                       OSString *uuidString;
+
+                       uuid = (char *)IOMalloc( kMaxBootVar );
+
+                       if (uuid) {
+                               if (!PE_parse_boot_argn( "boot-uuid", uuid, kMaxBootVar )) {
+                                       panic( "rd=uuid but no boot-uuid=<value> specified" );
+                               }
+                               uuidString = OSString::withCString( uuid );
+                               if (uuidString) {
+                                       IOService::publishResource( "boot-uuid", uuidString );
+                                       uuidString->release();
+                                       IOLog( "\nWaiting for boot volume with UUID %s\n", uuid );
+                                       matching = IOUUIDMatching();
+                                       mediaProperty = "boot-uuid-media";
+                               }
+                               IOFree( uuid, kMaxBootVar );
+                       }
+               } else {
+                       matching = IOBSDNameMatching( look );
+               }
+       }
+
+       if (!matching) {
+               OSString * astring;
+               // Match any HFS media
+
+               matching = IOService::serviceMatching( "IOMedia" );
+               astring = OSString::withCStringNoCopy("Apple_HFS");
+               if (astring) {
+                       matching->setObject("Content", astring);
+                       astring->release();
+               }
+       }
+
+       if (gIOKitDebug & kIOWaitQuietBeforeRoot) {
+               IOLog( "Waiting for matching to complete\n" );
+               IOService::getPlatform()->waitQuiet();
+       }
+
+       if (true && matching) {
+               OSSerialize * s = OSSerialize::withCapacity( 5 );
+
+               if (matching->serialize( s )) {
+                       IOLog( "Waiting on %s\n", s->text());
+                       s->release();
+               }
+       }
+
+       char namep[8];
+       if (needNetworkKexts
+           || PE_parse_boot_argn("-s", namep, sizeof(namep))) {
+               IOService::startDeferredMatches();
+       }
+
+       do {
+               t.tv_sec = ROOTDEVICETIMEOUT;
+               t.tv_nsec = 0;
+               matching->retain();
+               service = IOService::waitForService( matching, &t );
+               if ((!service) || (mountAttempts == 10)) {
+                       PE_display_icon( 0, "noroot");
+                       IOLog( "Still waiting for root device\n" );
+
+                       if (!debugInfoPrintedOnce) {
+                               debugInfoPrintedOnce = true;
+                               if (gIOKitDebug & kIOLogDTree) {
+                                       IOLog("\nDT plane:\n");
+                                       IOPrintPlane( gIODTPlane );
+                               }
+                               if (gIOKitDebug & kIOLogServiceTree) {
+                                       IOLog("\nService plane:\n");
+                                       IOPrintPlane( gIOServicePlane );
+                               }
+                               if (gIOKitDebug & kIOLogMemory) {
+                                       IOPrintMemory();
+                               }
+                       }
+               }
+       } while (!service);
+       matching->release();
+
+       if (service && mediaProperty) {
+               service = (IOService *)service->getProperty(mediaProperty);
+       }
+
+       mjr = 0;
+       mnr = 0;
+
+       // If the IOService we matched to is a subclass of IONetworkInterface,
+       // then make sure it has been registered with BSD and has a BSD name
+       // assigned.
+
+       if (service
+           && service->metaCast( "IONetworkInterface" )
+           && !IORegisterNetworkInterface( service )) {
+               service = NULL;
+       }
+
+       if (service) {
+               len = kMaxPathBuf;
+               service->getPath( str, &len, gIOServicePlane );
+               IOLog( "Got boot device = %s\n", str );
+
+               iostr = (OSString *) service->getProperty( kIOBSDNameKey );
+               if (iostr) {
+                       strlcpy( rootName, iostr->getCStringNoCopy(), rootNameSize );
+               }
+               off = (OSNumber *) service->getProperty( kIOBSDMajorKey );
+               if (off) {
+                       mjr = off->unsigned32BitValue();
+               }
+               off = (OSNumber *) service->getProperty( kIOBSDMinorKey );
+               if (off) {
+                       mnr = off->unsigned32BitValue();
+               }
+
+               if (service->metaCast( "IONetworkInterface" )) {
+                       flags |= 1;
+               }
+       } else {
+               IOLog( "Wait for root failed\n" );
+               strlcpy( rootName, "en0", rootNameSize );
+               flags |= 1;
+       }
+
+       IOLog( "BSD root: %s", rootName );
+       if (mjr) {
+               IOLog(", major %d, minor %d\n", mjr, mnr );
        } else {
-           matching = IOBSDNameMatching( look );
-       }
-    }
-
-    if( !matching) {
-       OSString * astring;
-       // Match any HFS media
-       
-        matching = IOService::serviceMatching( "IOMedia" );
-        astring = OSString::withCStringNoCopy("Apple_HFS");
-        if ( astring ) {
-            matching->setObject("Content", astring);
-            astring->release();
-        }
-    }
-
-    if( gIOKitDebug & kIOWaitQuietBeforeRoot ) {
-       IOLog( "Waiting for matching to complete\n" );
-       IOService::getPlatform()->waitQuiet();
-    }
-
-    if( true && matching) {
-        OSSerialize * s = OSSerialize::withCapacity( 5 );
-
-        if( matching->serialize( s )) {
-            IOLog( "Waiting on %s\n", s->text() );
-            s->release();
-        }
-    }
-
-    do {
-        t.tv_sec = ROOTDEVICETIMEOUT;
-        t.tv_nsec = 0;
-       matching->retain();
-        service = IOService::waitForService( matching, &t );
-       if( (!service) || (mountAttempts == 10)) {
-            PE_display_icon( 0, "noroot");
-            IOLog( "Still waiting for root device\n" );
-
-            if( !debugInfoPrintedOnce) {
-                debugInfoPrintedOnce = true;
-                if( gIOKitDebug & kIOLogDTree) {
-                    IOLog("\nDT plane:\n");
-                    IOPrintPlane( gIODTPlane );
-                }
-                if( gIOKitDebug & kIOLogServiceTree) {
-                    IOLog("\nService plane:\n");
-                    IOPrintPlane( gIOServicePlane );
-                }
-                if( gIOKitDebug & kIOLogMemory)
-                    IOPrintMemory();
-            }
-       }
-    } while( !service);
-    matching->release();
-
-    if ( service && mediaProperty ) {
-        service = (IOService *)service->getProperty(mediaProperty);
-    }
-
-    mjr = 0;
-    mnr = 0;
-
-    // If the IOService we matched to is a subclass of IONetworkInterface,
-    // then make sure it has been registered with BSD and has a BSD name
-    // assigned.
-
-    if ( service
-    &&   service->metaCast( "IONetworkInterface" )
-    &&   !IORegisterNetworkInterface( service ) )
-    {
-        service = 0;
-    }
-
-    if( service) {
-
-       len = kMaxPathBuf;
-       service->getPath( str, &len, gIOServicePlane );
-       IOLog( "Got boot device = %s\n", str );
-
-       iostr = (OSString *) service->getProperty( kIOBSDNameKey );
-       if( iostr)
-           strlcpy( rootName, iostr->getCStringNoCopy(), rootNameSize );
-       off = (OSNumber *) service->getProperty( kIOBSDMajorKey );
-       if( off)
-           mjr = off->unsigned32BitValue();
-       off = (OSNumber *) service->getProperty( kIOBSDMinorKey );
-       if( off)
-           mnr = off->unsigned32BitValue();
-
-       if( service->metaCast( "IONetworkInterface" ))
-           flags |= 1;
-
-    } else {
-
-       IOLog( "Wait for root failed\n" );
-        strlcpy( rootName, "en0", rootNameSize );
-        flags |= 1;
-    }
-
-    IOLog( "BSD root: %s", rootName );
-    if( mjr)
-       IOLog(", major %d, minor %d\n", mjr, mnr );
-    else
-       IOLog("\n");
-
-    *root = makedev( mjr, mnr );
-    *oflags = flags;
-
-    IOFree( str,  kMaxPathBuf + kMaxBootVar );
+               IOLog("\n");
+       }
+
+       *root = makedev( mjr, mnr );
+       *oflags = flags;
+
+       IOFree( str, kMaxPathBuf + kMaxBootVar );
 
 iofrootx:
-    if( (gIOKitDebug & (kIOLogDTree | kIOLogServiceTree | kIOLogMemory)) && !debugInfoPrintedOnce) {
-
-       IOService::getPlatform()->waitQuiet();
-        if( gIOKitDebug & kIOLogDTree) {
-            IOLog("\nDT plane:\n");
-            IOPrintPlane( gIODTPlane );
-        }
-        if( gIOKitDebug & kIOLogServiceTree) {
-            IOLog("\nService plane:\n");
-            IOPrintPlane( gIOServicePlane );
-        }
-        if( gIOKitDebug & kIOLogMemory)
-            IOPrintMemory();
-    }
-
-    return( kIOReturnSuccess );
+       if ((gIOKitDebug & (kIOLogDTree | kIOLogServiceTree | kIOLogMemory)) && !debugInfoPrintedOnce) {
+               IOService::getPlatform()->waitQuiet();
+               if (gIOKitDebug & kIOLogDTree) {
+                       IOLog("\nDT plane:\n");
+                       IOPrintPlane( gIODTPlane );
+               }
+               if (gIOKitDebug & kIOLogServiceTree) {
+                       IOLog("\nService plane:\n");
+                       IOPrintPlane( gIOServicePlane );
+               }
+               if (gIOKitDebug & kIOLogMemory) {
+                       IOPrintMemory();
+               }
+       }
+
+       return kIOReturnSuccess;
 }
 
-bool IORamDiskBSDRoot(void)
+bool
+IORamDiskBSDRoot(void)
 {
-    char rdBootVar[kMaxBootVar];
-    if (PE_parse_boot_argn("rd", rdBootVar, kMaxBootVar )
-     || PE_parse_boot_argn("rootdev", rdBootVar, kMaxBootVar )) {
-        if((rdBootVar[0] == 'm') && (rdBootVar[1] == 'd') && (rdBootVar[3] == 0)) {
-            return true;
-        }
-    }
-    return false;
+       char rdBootVar[kMaxBootVar];
+       if (PE_parse_boot_argn("rd", rdBootVar, kMaxBootVar )
+           || PE_parse_boot_argn("rootdev", rdBootVar, kMaxBootVar )) {
+               if ((rdBootVar[0] == 'm') && (rdBootVar[1] == 'd') && (rdBootVar[3] == 0)) {
+                       return true;
+               }
+       }
+       return false;
 }
 
-void IOSecureBSDRoot(const char * rootName)
+void
+IOSecureBSDRoot(const char * rootName)
 {
 #if CONFIG_EMBEDDED
-    int              tmpInt;
-    IOReturn         result;
-    IOPlatformExpert *pe;
-    OSDictionary     *matching;
-    const OSSymbol   *functionName = OSSymbol::withCStringNoCopy("SecureRootName");
-    
-    matching = IOService::serviceMatching("IOPlatformExpert");
-    assert(matching);
-    pe = (IOPlatformExpert *) IOService::waitForMatchingService(matching, 30ULL * kSecondScale);
-    matching->release();
-    assert(pe);
-    // Returns kIOReturnNotPrivileged is the root device is not secure.
-    // Returns kIOReturnUnsupported if "SecureRootName" is not implemented.
-    result = pe->callPlatformFunction(functionName, false, (void *)rootName, (void *)0, (void *)0, (void *)0);
-    functionName->release();
-    OSSafeReleaseNULL(pe);
-    
-    if (result == kIOReturnNotPrivileged) {
-        mdevremoveall();
-    } else if (result == kIOReturnSuccess) {
-        // If we are booting with a secure root, and we have the right
-       // boot-arg, we will want to panic on exception triage.  This
-       // behavior is intended as a debug aid (we can look at why an
-       // exception occured in the kernel debugger).
-        if (PE_parse_boot_argn("-panic_on_exception_triage", &tmpInt, sizeof(tmpInt))) {
-            panic_on_exception_triage = 1;
-        }
-    }
+       IOReturn         result;
+       IOPlatformExpert *pe;
+       OSDictionary     *matching;
+       const OSSymbol   *functionName = OSSymbol::withCStringNoCopy("SecureRootName");
+
+       matching = IOService::serviceMatching("IOPlatformExpert");
+       assert(matching);
+       pe = (IOPlatformExpert *) IOService::waitForMatchingService(matching, 30ULL * kSecondScale);
+       matching->release();
+       assert(pe);
+       // Returns kIOReturnNotPrivileged is the root device is not secure.
+       // Returns kIOReturnUnsupported if "SecureRootName" is not implemented.
+       result = pe->callPlatformFunction(functionName, false, (void *)rootName, (void *)NULL, (void *)NULL, (void *)NULL);
+       functionName->release();
+       OSSafeReleaseNULL(pe);
+
+       if (result == kIOReturnNotPrivileged) {
+               mdevremoveall();
+       }
 
 #endif  // CONFIG_EMBEDDED
 }
@@ -699,50 +742,55 @@ void IOSecureBSDRoot(const char * rootName)
 void *
 IOBSDRegistryEntryForDeviceTree(char * path)
 {
-    return (IORegistryEntry::fromPath(path, gIODTPlane));
+       return IORegistryEntry::fromPath(path, gIODTPlane);
 }
 
 void
 IOBSDRegistryEntryRelease(void * entry)
 {
-    IORegistryEntry * regEntry = (IORegistryEntry *)entry;
+       IORegistryEntry * regEntry = (IORegistryEntry *)entry;
 
-    if (regEntry)
-       regEntry->release();
-    return;
+       if (regEntry) {
+               regEntry->release();
+       }
+       return;
 }
 
 const void *
-IOBSDRegistryEntryGetData(void * entry, char * property_name, 
-                         int * packet_length)
+IOBSDRegistryEntryGetData(void * entry, char * property_name,
+    int * packet_length)
 {
-    OSData *           data;
-    IORegistryEntry *  regEntry = (IORegistryEntry *)entry;
-
-    data = (OSData *) regEntry->getProperty(property_name);
-    if (data) {
-       *packet_length = data->getLength();
-        return (data->getBytesNoCopy());
-    }
-    return (NULL);
+       OSData *            data;
+       IORegistryEntry *   regEntry = (IORegistryEntry *)entry;
+
+       data = (OSData *) regEntry->getProperty(property_name);
+       if (data) {
+               *packet_length = data->getLength();
+               return data->getBytesNoCopy();
+       }
+       return NULL;
 }
 
-kern_return_t IOBSDGetPlatformUUID( uuid_t uuid, mach_timespec_t timeout )
+kern_return_t
+IOBSDGetPlatformUUID( uuid_t uuid, mach_timespec_t timeout )
 {
-    IOService * resources;
-    OSString *  string;
+       IOService * resources;
+       OSString *  string;
 
-    resources = IOService::waitForService( IOService::resourceMatching( kIOPlatformUUIDKey ), ( timeout.tv_sec || timeout.tv_nsec ) ? &timeout : 0 );
-    if ( resources == 0 ) return KERN_OPERATION_TIMED_OUT;
+       resources = IOService::waitForService( IOService::resourceMatching( kIOPlatformUUIDKey ), (timeout.tv_sec || timeout.tv_nsec) ? &timeout : NULL );
+       if (resources == NULL) {
+               return KERN_OPERATION_TIMED_OUT;
+       }
 
-    string = ( OSString * ) IOService::getPlatform( )->getProvider( )->getProperty( kIOPlatformUUIDKey );
-    if ( string == 0 ) return KERN_NOT_SUPPORTED;
+       string = (OSString *) IOService::getPlatform()->getProvider()->getProperty( kIOPlatformUUIDKey );
+       if (string == NULL) {
+               return KERN_NOT_SUPPORTED;
+       }
 
-    uuid_parse( string->getCStringNoCopy( ), uuid );
+       uuid_parse( string->getCStringNoCopy(), uuid );
 
-    return KERN_SUCCESS;
+       return KERN_SUCCESS;
 }
-
 } /* extern "C" */
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
@@ -755,185 +803,246 @@ kern_return_t IOBSDGetPlatformUUID( uuid_t uuid, mach_timespec_t timeout )
 #include <IOKit/IOBufferMemoryDescriptor.h>
 
 IOPolledFileIOVars * gIOPolledCoreFileVars;
+kern_return_t gIOPolledCoreFileOpenRet = kIOReturnNotReady;
+IOPolledCoreFileMode_t gIOPolledCoreFileMode = kIOPolledCoreFileModeNotInitialized;
 
 #if IOPOLLED_COREFILE
 
-static IOReturn 
-IOOpenPolledCoreFile(const char * filename)
-{
-    IOReturn err;
-    unsigned int debug;
+#if defined(XNU_TARGET_OS_BRIDGE)
+// On bridgeOS allocate a 150MB corefile and leave 150MB free
+#define kIOCoreDumpSize         150ULL*1024ULL*1024ULL
+#define kIOCoreDumpFreeSize     150ULL*1024ULL*1024ULL
 
-    if (gIOPolledCoreFileVars)                             return (kIOReturnBusy);
-    if (!IOPolledInterface::gMetaClass.getInstanceCount()) return (kIOReturnUnsupported);
+#elif CONFIG_EMBEDDED /* defined(XNU_TARGET_OS_BRIDGE) */
+// On embedded devices with >3GB DRAM we allocate a 500MB corefile
+// otherwise allocate a 350MB corefile. Leave 350 MB free
 
-    debug = 0;
-    PE_parse_boot_argn("debug", &debug, sizeof (debug));
-    if (DB_DISABLE_LOCAL_CORE & debug)                     return (kIOReturnUnsupported);
+#define kIOCoreDumpMinSize      350ULL*1024ULL*1024ULL
+#define kIOCoreDumpLargeSize    500ULL*1024ULL*1024ULL
 
-    err = IOPolledFileOpen(filename, kIOCoreDumpSize, kIOCoreDumpFreeSize,
-                           NULL, 0,
-                           &gIOPolledCoreFileVars, NULL, NULL, 0);
-    if (kIOReturnSuccess != err)                           return (err);
+#define kIOCoreDumpFreeSize     350ULL*1024ULL*1024ULL
 
-    err = IOPolledFilePollersSetup(gIOPolledCoreFileVars, kIOPolledPreflightCoreDumpState);
-    if (kIOReturnSuccess != err)
-    {
-       IOPolledFileClose(&gIOPolledCoreFileVars, NULL, NULL, 0, 0, 0);
-    }
+#else /* defined(XNU_TARGET_OS_BRIDGE) */
+// on macOS devices allocate a corefile sized at 1GB / 32GB of DRAM,
+// fallback to a 1GB corefile and leave at least 1GB free
+#define kIOCoreDumpMinSize              1024ULL*1024ULL*1024ULL
+#define kIOCoreDumpIncrementalSize      1024ULL*1024ULL*1024ULL
 
-    return (err);
-}
+#define kIOCoreDumpFreeSize     1024ULL*1024ULL*1024ULL
 
-static void 
-IOClosePolledCoreFile(void)
+// on older macOS devices we allocate a 1MB file at boot
+// to store a panic time stackshot
+#define kIOStackshotFileSize    1024ULL*1024ULL
+
+#endif /* defined(XNU_TARGET_OS_BRIDGE) */
+
+static IOPolledCoreFileMode_t
+GetCoreFileMode()
 {
-    IOPolledFilePollersClose(gIOPolledCoreFileVars, kIOPolledPostflightCoreDumpState);
-    IOPolledFileClose(&gIOPolledCoreFileVars, NULL, NULL, 0, 0, 0);
+       if (on_device_corefile_enabled()) {
+               return kIOPolledCoreFileModeCoredump;
+       } else if (panic_stackshot_to_disk_enabled()) {
+               return kIOPolledCoreFileModeStackshot;
+       } else {
+               return kIOPolledCoreFileModeDisabled;
+       }
 }
 
-static thread_call_t gIOOpenPolledCoreFileTC;
-static IONotifier  * gIOPolledCoreFileNotifier;
-static IONotifier  * gIOPolledCoreFileInterestNotifier;
-
-static IOReturn 
-KernelCoreMediaInterest(void * target, void * refCon,
-                       UInt32 messageType, IOService * provider,
-                       void * messageArgument, vm_size_t argSize )
+static void
+IOCoreFileGetSize(uint64_t *ideal_size, uint64_t *fallback_size, uint64_t *free_space_to_leave, IOPolledCoreFileMode_t mode)
 {
-    if (kIOMessageServiceIsTerminated == messageType)
-    {
-       gIOPolledCoreFileInterestNotifier->remove();
-       gIOPolledCoreFileInterestNotifier = 0;
-       IOClosePolledCoreFile();
-    }
-
-    return (kIOReturnSuccess);
+       unsigned int requested_corefile_size = 0;
+
+       *ideal_size = *fallback_size = *free_space_to_leave = 0;
+
+#if defined(XNU_TARGET_OS_BRIDGE)
+#pragma unused(mode)
+       *ideal_size = *fallback_size = kIOCoreDumpSize;
+       *free_space_to_leave = kIOCoreDumpFreeSize;
+#elif CONFIG_EMBEDDED /* defined(XNU_TARGET_OS_BRIDGE) */
+#pragma unused(mode)
+       *ideal_size = *fallback_size = kIOCoreDumpMinSize;
+
+       if (max_mem > (3 * 1024ULL * 1024ULL * 1024ULL)) {
+               *ideal_size = kIOCoreDumpLargeSize;
+       }
+
+       *free_space_to_leave = kIOCoreDumpFreeSize;
+#else /* defined(XNU_TARGET_OS_BRIDGE) */
+       if (mode == kIOPolledCoreFileModeCoredump) {
+               *ideal_size = *fallback_size = kIOCoreDumpMinSize;
+               if (kIOCoreDumpIncrementalSize != 0 && max_mem > (32 * 1024ULL * 1024ULL * 1024ULL)) {
+                       *ideal_size = ((ROUNDUP(max_mem, (32 * 1024ULL * 1024ULL * 1024ULL)) / (32 * 1024ULL * 1024ULL * 1024ULL)) * kIOCoreDumpIncrementalSize);
+               }
+               *free_space_to_leave = kIOCoreDumpFreeSize;
+       } else if (mode == kIOPolledCoreFileModeStackshot) {
+               *ideal_size = *fallback_size = *free_space_to_leave = kIOStackshotFileSize;
+       }
+#endif /* defined(XNU_TARGET_OS_BRIDGE) */
+       // If a custom size was requested, override the ideal and requested sizes
+       if (PE_parse_boot_argn("corefile_size_mb", &requested_corefile_size, sizeof(requested_corefile_size))) {
+               IOLog("Boot-args specify %d MB kernel corefile\n", requested_corefile_size);
+
+               *ideal_size = *fallback_size = (requested_corefile_size * 1024ULL * 1024ULL);
+       }
+
+       return;
 }
 
 static void
-OpenKernelCoreMedia(thread_call_param_t p0, thread_call_param_t p1)
+IOOpenPolledCoreFile(thread_call_param_t __unused, thread_call_param_t corefilename)
 {
-    IOService * newService;
-    OSString  * string;
-    char        filename[16];
-
-    newService = (IOService *) p1;
-    do
-    {
-       if (gIOPolledCoreFileVars) break;
-       string = OSDynamicCast(OSString, newService->getProperty(kIOBSDNameKey));
-       if (!string) break;
-       snprintf(filename, sizeof(filename), "/dev/%s", string->getCStringNoCopy());
-       if (kIOReturnSuccess != IOOpenPolledCoreFile(filename)) break;
-       gIOPolledCoreFileInterestNotifier = newService->registerInterest(
-                               gIOGeneralInterest, &KernelCoreMediaInterest, NULL, 0);
-    }
-    while (false);
-
-    newService->release();
+       assert(corefilename != NULL);
+
+       IOReturn err;
+       char *filename = (char *) corefilename;
+       uint64_t corefile_size_bytes = 0, corefile_fallback_size_bytes = 0, free_space_to_leave_bytes = 0;
+       IOPolledCoreFileMode_t mode_to_init = GetCoreFileMode();
+
+       if (gIOPolledCoreFileVars) {
+               return;
+       }
+       if (!IOPolledInterface::gMetaClass.getInstanceCount()) {
+               return;
+       }
+
+       if (mode_to_init == kIOPolledCoreFileModeDisabled) {
+               gIOPolledCoreFileMode = kIOPolledCoreFileModeDisabled;
+               return;
+       }
+
+       // We'll overwrite this once we open the file, we update this to mark that we have made
+       // it past initialization
+       gIOPolledCoreFileMode = kIOPolledCoreFileModeClosed;
+
+       IOCoreFileGetSize(&corefile_size_bytes, &corefile_fallback_size_bytes, &free_space_to_leave_bytes, mode_to_init);
+
+       do {
+               err = IOPolledFileOpen(filename, kIOPolledFileCreate, corefile_size_bytes, free_space_to_leave_bytes,
+                   NULL, 0, &gIOPolledCoreFileVars, NULL, NULL, NULL);
+               if (kIOReturnSuccess == err) {
+                       break;
+               } else if (kIOReturnNoSpace == err) {
+                       IOLog("Failed to open corefile of size %llu MB (low disk space)",
+                           (corefile_size_bytes / (1024ULL * 1024ULL)));
+                       if (corefile_size_bytes == corefile_fallback_size_bytes) {
+                               gIOPolledCoreFileOpenRet = err;
+                               return;
+                       }
+               } else {
+                       IOLog("Failed to open corefile of size %llu MB (returned error 0x%x)\n",
+                           (corefile_size_bytes / (1024ULL * 1024ULL)), err);
+                       gIOPolledCoreFileOpenRet = err;
+                       return;
+               }
+
+               err = IOPolledFileOpen(filename, kIOPolledFileCreate, corefile_fallback_size_bytes, free_space_to_leave_bytes,
+                   NULL, 0, &gIOPolledCoreFileVars, NULL, NULL, NULL);
+               if (kIOReturnSuccess != err) {
+                       IOLog("Failed to open corefile of size %llu MB (returned error 0x%x)\n",
+                           (corefile_fallback_size_bytes / (1024ULL * 1024ULL)), err);
+                       gIOPolledCoreFileOpenRet = err;
+                       return;
+               }
+       } while (false);
+
+       gIOPolledCoreFileOpenRet = IOPolledFilePollersSetup(gIOPolledCoreFileVars, kIOPolledPreflightCoreDumpState);
+       if (kIOReturnSuccess != gIOPolledCoreFileOpenRet) {
+               IOPolledFileClose(&gIOPolledCoreFileVars, 0, NULL, 0, 0, 0);
+               IOLog("IOPolledFilePollersSetup for corefile failed with error: 0x%x\n", err);
+       } else {
+               IOLog("Opened corefile of size %llu MB\n", (corefile_size_bytes / (1024ULL * 1024ULL)));
+               gIOPolledCoreFileMode = mode_to_init;
+       }
+
+       return;
 }
 
-static bool 
-NewKernelCoreMedia(void * target, void * refCon,
-                  IOService * newService,
-                  IONotifier * notifier)
+static void
+IOClosePolledCoreFile(void)
 {
-    static volatile UInt32 onlyOneCorePartition = 0;
-    do
-    {
-       if (!OSCompareAndSwap(0, 1, &onlyOneCorePartition)) break;
-       if (gIOPolledCoreFileVars)    break;
-        if (!gIOOpenPolledCoreFileTC) break;
-        newService = newService->getProvider();
-        if (!newService)              break;
-        newService->retain();
-       thread_call_enter1(gIOOpenPolledCoreFileTC, newService);
-    }
-    while (false);
-
-    return (false);
+       gIOPolledCoreFileOpenRet = kIOReturnNotOpen;
+       gIOPolledCoreFileMode = kIOPolledCoreFileModeClosed;
+       IOPolledFilePollersClose(gIOPolledCoreFileVars, kIOPolledPostflightCoreDumpState);
+       IOPolledFileClose(&gIOPolledCoreFileVars, 0, NULL, 0, 0, 0);
 }
 
 #endif /* IOPOLLED_COREFILE */
 
-extern "C" void 
+extern "C" void
 IOBSDMountChange(struct mount * mp, uint32_t op)
 {
 #if IOPOLLED_COREFILE
+       uint64_t flags;
+       char path[128];
+       int pathLen;
+       vnode_t vn;
+       int result;
 
-    OSDictionary * bsdMatching;
-    OSDictionary * mediaMatching;
-    OSString     * string;
-
-    if (!gIOPolledCoreFileNotifier) do
-    {
-       if (!gIOOpenPolledCoreFileTC) gIOOpenPolledCoreFileTC = thread_call_allocate(&OpenKernelCoreMedia, NULL);
-       bsdMatching = IOService::serviceMatching("IOMediaBSDClient");
-       if (!bsdMatching) break;
-       mediaMatching = IOService::serviceMatching("IOMedia");
-       string = OSString::withCStringNoCopy("5361644D-6163-11AA-AA11-00306543ECAC");
-       if (!string || !mediaMatching) break;
-       mediaMatching->setObject("Content", string);
-       string->release();
-       bsdMatching->setObject(gIOParentMatchKey, mediaMatching);
-       mediaMatching->release();
-
-       gIOPolledCoreFileNotifier = IOService::addMatchingNotification(
-                                                 gIOFirstMatchNotification, bsdMatching, 
-                                                 &NewKernelCoreMedia, NULL, NULL, -1000);
-    }
-    while (false);
-
-#if CONFIG_EMBEDDED
-    uint64_t flags;
-    char path[128];
-    int pathLen;
-    vnode_t vn;
-    int result;
-
-    switch (op)
-    {
+       switch (op) {
        case kIOMountChangeMount:
        case kIOMountChangeDidResize:
 
-           if (gIOPolledCoreFileVars) break;
-           flags = vfs_flags(mp);
-           if (MNT_RDONLY & flags) break;
-           if (!(MNT_LOCAL & flags)) break;
-
-           vn = vfs_vnodecovered(mp);
-           if (!vn) break;
-           pathLen = sizeof(path);
-           result = vn_getpath(vn, &path[0], &pathLen);
-           vnode_put(vn);
-           if (0 != result) break;
-           if (!pathLen) break;
-           if (0 != bcmp(path, kIOCoreDumpPath, pathLen - 1)) break;
-           IOOpenPolledCoreFile(kIOCoreDumpPath);
-           break;
+               if (gIOPolledCoreFileVars) {
+                       break;
+               }
+               flags = vfs_flags(mp);
+               if (MNT_RDONLY & flags) {
+                       break;
+               }
+               if (!(MNT_LOCAL & flags)) {
+                       break;
+               }
+
+               vn = vfs_vnodecovered(mp);
+               if (!vn) {
+                       break;
+               }
+               pathLen = sizeof(path);
+               result = vn_getpath(vn, &path[0], &pathLen);
+               vnode_put(vn);
+               if (0 != result) {
+                       break;
+               }
+               if (!pathLen) {
+                       break;
+               }
+#if defined(XNU_TARGET_OS_BRIDGE)
+               // on bridgeOS systems we put the core in /private/var/internal. We don't
+               // want to match with /private/var because /private/var/internal is often mounted
+               // over /private/var
+               if ((pathLen - 1) < (int) strlen("/private/var/internal")) {
+                       break;
+               }
+#endif
+               if (0 != strncmp(path, kIOCoreDumpPath, pathLen - 1)) {
+                       break;
+               }
+
+               thread_call_enter1(corefile_open_call, (void *) kIOCoreDumpPath);
+               break;
 
        case kIOMountChangeUnmount:
        case kIOMountChangeWillResize:
-           if (gIOPolledCoreFileVars && (mp == kern_file_mount(gIOPolledCoreFileVars->fileRef)))
-           {
-               IOClosePolledCoreFile();
-           }
-           break;
-    }
-#endif /* CONFIG_EMBEDDED */
+               if (gIOPolledCoreFileVars && (mp == kern_file_mount(gIOPolledCoreFileVars->fileRef))) {
+                       thread_call_cancel_wait(corefile_open_call);
+                       IOClosePolledCoreFile();
+               }
+               break;
+       }
 #endif /* IOPOLLED_COREFILE */
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-extern "C" boolean_t 
+extern "C" boolean_t
 IOTaskHasEntitlement(task_t task, const char * entitlement)
 {
-    OSObject * obj;
-    obj = IOUserClient::copyClientEntitlement(task, entitlement);
-    if (!obj) return (false);
-    obj->release();
-    return (obj != kOSBooleanFalse);
+       OSObject * obj;
+       obj = IOUserClient::copyClientEntitlement(task, entitlement);
+       if (!obj) {
+               return false;
+       }
+       obj->release();
+       return obj != kOSBooleanFalse;
 }
-