system_cmds-880.100.5.tar.gz

[apple/system_cmds.git] / dynamic_pager.tproj / dynamic_pager.c

diff --git a/dynamic_pager.tproj/dynamic_pager.c b/dynamic_pager.tproj/dynamic_pager.c
index c168eab7e4551218fad2dab1fd63d235c72f4118..deb9379c191e80c31b9b4738e0d600b5664b7621 100644 (file)
--- a/dynamic_pager.tproj/dynamic_pager.c
+++ b/dynamic_pager.tproj/dynamic_pager.c
@@ -1,613 +1,114 @@
-/* File created by Chris Youngworth, Apple Computer 2/11/99 */
-
-

 #define mig_external
 
 #define mig_external
 

-#include <mach/port.h>
-#include <mach/mach_error.h>
-#include <mach/mach_traps.h>
-#include <mach/mach.h>
-#ifndef MACH_BSD
-#define MACH_BSD
-#endif
-#include <mach/bootstrap.h>
-#include <mach/mach_syscalls.h>
-#include <mach/mig_errors.h>
-#include <sys/param.h>

 #include <sys/mount.h>
 #include <sys/mount.h>

-#include <sys/file.h>
-#include <sys/mman.h>

 #include <sys/stat.h>
 #include <sys/sysctl.h>
 #include <sys/stat.h>
 #include <sys/sysctl.h>

-#include <sys/gmon.h>
-#include <errno.h>
-#include <kvm.h>
-#include <limits.h>

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

-#include <nlist.h>
-#include <ctype.h>

 #include <unistd.h> 
 #include <unistd.h> 

-#include <paths.h>
-
-#include <default_pager/default_pager_types.h>
-#include <default_pager_alerts_server.h>
-#include <backing_store_alerts.h>
-#include <backing_store_triggers_server.h>
-
+#include <dirent.h>

 
 /*
 
 /*

- * HI_WATER_DEFAULT set to this funny value to 
- * match the size that the low space application
- * is asking for... need to keep MINIMUM_SIZE
- * above this value.
+ * We don't exit with a non-zero status anywhere here for 2 reasons:
+ * - the kernel can continue to create swapfiles in "/private/var/vm/swapfile<index>"
+ * - we want this job to run only once at boot and exit regardless of whether:
+ *     -- it could clean up the swap directory
+ *     -- it could set the prefix for the swapfile name.

  */
  */

-#define HI_WATER_DEFAULT 40000000
-#define MINIMUM_SIZE (1024 * 1024 * 64)
-#define MAXIMUM_SIZE  (1024 * 1024 * 1024)
-
-#define MAX_LIMITS 8
-
-
-struct limit {
-        unsigned int size;
-        unsigned int low_water;
-} limits[MAX_LIMITS];
-
-
-int    debug = 0;
-int     max_valid  = 0;
-int    file_count = 0;
-unsigned int   hi_water;
-unsigned int   local_hi_water;
-int    priority = 0;
-int    options  = 0;
-char   fileroot[512];
-
-
-/* global parameters for application notification option */
-mach_port_t    trigger_port = MACH_PORT_NULL;
-mach_port_t    notify_port = MACH_PORT_NULL;
-unsigned int   notify_high = 0;
-unsigned int   bs_recovery;
-
-/*
-void   setprof __P((struct kvmvars *kvp, int state));
-void   dumpstate __P((struct kvmvars *kvp));
-void   reset __P((struct kvmvars *kvp));
-*/
-
-
-
-mach_msg_return_t
-server_alert_loop(
-    mach_msg_size_t max_size,
-    mach_port_t rcv_name,
-    mach_msg_options_t options)
-{
-    mig_reply_error_t *bufRequest = 0, *bufReply = 0;
-    register mach_msg_return_t mr;
-    register kern_return_t kr;
-
-    if ((kr = vm_allocate(mach_task_self(),
-                     (vm_address_t *)&bufRequest,
-                     max_size + MAX_TRAILER_SIZE,
-                     TRUE)) != KERN_SUCCESS)
-      return kr;
-    if ((kr = vm_protect(mach_task_self(),
-                     (vm_address_t)bufRequest,
-                     max_size + MAX_TRAILER_SIZE,
-                    FALSE, VM_PROT_ALL)) != KERN_SUCCESS)
-      return kr;
-    mlock(bufRequest, max_size + MAX_TRAILER_SIZE);
-    if ((kr = vm_allocate(mach_task_self(),
-                     (vm_address_t *)&bufReply,
-                     max_size + MAX_TRAILER_SIZE,
-                     TRUE)) != KERN_SUCCESS)
-      return kr;
-    if ((kr = vm_protect(mach_task_self(),
-                     (vm_address_t)bufReply,
-                     max_size + MAX_TRAILER_SIZE,
-                    FALSE, VM_PROT_ALL)) != KERN_SUCCESS)
-      return kr;
-    mlock(bufReply, max_size + MAX_TRAILER_SIZE);
-    while(TRUE) {
-       mr = mach_msg_overwrite_trap(&bufRequest->Head, MACH_RCV_MSG|options,
-                                 0, max_size, rcv_name,
-                                 MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL,
-                                 (mach_msg_header_t *) 0, 0);
-        if (mr == MACH_MSG_SUCCESS) {
-           /* we have a request message */
-
-           if(!(default_pager_alerts_server(
-                               &bufRequest->Head, &bufReply->Head)))
-               backing_store_triggers_server(
-                               &bufRequest->Head, &bufReply->Head);
-
-           if (!(bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX) &&
-               bufReply->RetCode != KERN_SUCCESS) {
-               if (bufReply->RetCode == MIG_NO_REPLY)
-                /*
-                 * This return code is a little tricky--
-                 * it appears that the demux routine found an
-                 * error of some sort, but since that error
-                 * would not normally get returned either to
-                 * the local user or the remote one, we pretend it's
-                 * ok.
-                 */
-
-               bufRequest->Head.msgh_remote_port = MACH_PORT_NULL;
-               mach_msg_destroy(&bufRequest->Head);
-              continue;
-           }
-
-           if (bufReply->Head.msgh_remote_port == MACH_PORT_NULL) {
-              /* no reply port, so destroy the reply */
-              if (bufReply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)
-                  mach_msg_destroy(&bufReply->Head);
-          } else {
-               break;
-          }
-       } else {
-          break;
-       }   
-    } 
-
-    (void)vm_deallocate(mach_task_self(),
-                    (vm_address_t) bufRequest,
-                    max_size + MAX_TRAILER_SIZE);
-    (void)vm_deallocate(mach_task_self(),
-                    (vm_address_t) bufReply,
-                    max_size + MAX_TRAILER_SIZE);
-    return KERN_FAILURE;
-
-}       
-

 
 

-kern_return_t
-backing_store_triggers(dynamic_pager, hi_wat, flags, port)
-               mach_port_t     dynamic_pager;
-               int             hi_wat;
-               int             flags;
-               mach_port_t     port;
+static void
+clean_swap_directory(const char *path)

 {
 {

-        int cur_limits;
-       
-       if (file_count > max_valid)
-               cur_limits = max_valid;
-       else
-               cur_limits = file_count;
-
-       if((hi_wat + limits[cur_limits].size) > limits[cur_limits].low_water) 
-               return KERN_FAILURE; /* let ipc system clean up port */
-
-       /* If there was a previous registration, throw it away */
-       if (notify_port != MACH_PORT_NULL) {
-               mach_port_deallocate(mach_task_self(), notify_port);
-               notify_port = MACH_PORT_NULL;
+       DIR *dir;
+       struct dirent *entry;
+       char buf[1024];
+
+       dir = opendir(path);
+       if (dir == NULL) {
+               fprintf(stderr,"dynamic_pager: cannot open swap directory %s\n", path);
+               exit(0);

        }
 
        }
 

-       notify_port = port;
-       notify_high = hi_wat;
-       if(hi_water < notify_high) {
-               local_hi_water = notify_high;
-       } else {
-               local_hi_water = hi_water;
-       }
-       if(notify_high > hi_water) {
-               default_pager_space_alert(trigger_port, HI_WAT_ALERT);
-       }
-       return KERN_SUCCESS;
-}
-
-
-kern_return_t
-default_pager_space_alert(alert_port, flags)
-       mach_port_t     alert_port;
-       int     flags;
-{
-       char subfile[512];
-       FILE *file_ptr;
-       off_t   filesize;
-       int     error;
-       kern_return_t   ret;
-        int cur_limits;
-       unsigned int cur_size;
-       unsigned int notifications;
-
-       
-       if(flags & HI_WAT_ALERT) {
-
-               file_count++;
-
-               if (file_count > max_valid)
-                       cur_limits = max_valid;
-               else
-                       cur_limits = file_count;
-
-               cur_size = limits[cur_limits].size;
-               filesize = cur_size;
-
-               /*
-                * because the LO_WAT threshold changes relative to
-                * the size of the swap file we're creating
-                * we need to reset the LO_WAT_ALERT threshold each
-                * time we create a new swap file
-                */
-               if (limits[cur_limits].low_water)
-                       notifications = HI_WAT_ALERT | LO_WAT_ALERT;
-               else
-                       notifications = HI_WAT_ALERT;
-
-               sprintf(subfile, "%s%d", fileroot, file_count);
-               file_ptr = fopen(subfile, "w+");
-               fchmod(fileno(file_ptr), (mode_t)01600);
-               error = fcntl(fileno(file_ptr), F_SETSIZE, &filesize);
-               if(error) {
-                       error = ftruncate(fileno(file_ptr), filesize);
+       while ((entry = readdir(dir)) != NULL) {
+               if (entry->d_namlen>= 4 && strncmp(entry->d_name, "swap", 4) == 0) {
+                       snprintf(buf, sizeof buf, "%s/%s", path, entry->d_name);
+                       unlink(buf);

                }
                }

-               fclose(file_ptr);
-
-               if(error == -1) {
-                       unlink(subfile);
-                       file_count--;
-
-                       if (file_count > max_valid)
-                               cur_limits = max_valid;
-                       else
-                               cur_limits = file_count;
-
-                       if (limits[cur_limits].low_water)
-                               notifications = HI_WAT_ALERT | LO_WAT_ALERT;
-                       else
-                               notifications = HI_WAT_ALERT;
-
-                       local_hi_water = local_hi_water>>2;
-                       if(notify_high >= (local_hi_water)) {
-                               if(notify_port != MACH_PORT_NULL) {
-                                       /* notify monitoring app of */
-                                       /* backing store shortage  */
-                                       backing_store_alert(notify_port,
-                                                               HI_WAT_ALERT);
-                                       mach_port_deallocate(mach_task_self(), 
-                                                               notify_port);
-                                       notify_port = MACH_PORT_NULL;
-                                       notify_high = 0;
-                               }
-                       }
-                       macx_triggers(local_hi_water, limits[cur_limits].low_water, notifications, alert_port);
-               } else {
-                       if(hi_water < notify_high) {
-                               if(local_hi_water < notify_high) {
-                                  bs_recovery = notify_high - local_hi_water;
-                               }
-                               local_hi_water = notify_high;
-                       } else {
-                               if(local_hi_water < hi_water) {
-                                  bs_recovery = hi_water - local_hi_water;
-                               }
-                               local_hi_water = hi_water;
-                       }
-                       ret = macx_swapon(subfile, flags, cur_size, priority);
-
-                       if(ret) {
-                               unlink(subfile);
-                               file_count--;
-
-                               if (file_count > max_valid)
-                                       cur_limits = max_valid;
-                               else
-                                       cur_limits = file_count;
-
-                               if (limits[cur_limits].low_water)
-                                       notifications = HI_WAT_ALERT | LO_WAT_ALERT;
-                               else
-                                       notifications = HI_WAT_ALERT;
-
-                               local_hi_water = local_hi_water>>2;
-                               if(notify_high >= (local_hi_water)) {
-                                       if(notify_port != MACH_PORT_NULL) {
-                                               /* notify monitoring app of */
-                                               /* backing store shortage  */
-                                               backing_store_alert(
-                                                       notify_port,
-                                                       HI_WAT_ALERT);
-                                               mach_port_deallocate(
-                                                       mach_task_self(), 
-                                                       notify_port);
-                                               notify_port = MACH_PORT_NULL;
-                                               notify_high = 0;
-                                       }
-                               }
-                               macx_triggers(local_hi_water, limits[cur_limits].low_water, notifications, alert_port);
-                       } else if(bs_recovery <= cur_size) {
-                               if((bs_recovery != 0) && (notify_port)) {
-                                       backing_store_alert(notify_port,
-                                                               LO_WAT_ALERT);
-                                       mach_port_deallocate(mach_task_self(), 
-                                                               notify_port);
-                                       notify_port = MACH_PORT_NULL;
-                                       notify_high = 0;
-                                       bs_recovery = 0;
-                               }
-                       } else 
-                               bs_recovery = bs_recovery-cur_size;
-               }
-               macx_triggers(local_hi_water, limits[cur_limits].low_water, notifications, alert_port);

        }
        }

-       if(flags & LO_WAT_ALERT) {
-               sprintf(subfile, "%s%d", fileroot, file_count);
-               if(hi_water < notify_high) {
-                       local_hi_water = notify_high;
-               } else {
-                       local_hi_water = hi_water;
-               }
-               if((bs_recovery != 0) && (notify_port != MACH_PORT_NULL)) {
-                       backing_store_alert(notify_port, LO_WAT_ALERT);
-                       mach_port_deallocate(mach_task_self(), notify_port);
-                       notify_port = MACH_PORT_NULL;
-                       notify_high = 0;
-                       bs_recovery = 0;
-               }
-               if((error = macx_swapoff(subfile, flags)) == 0) {
-
-                       unlink(subfile);
-                       file_count--;

 
 

-                       if (file_count > max_valid)
-                               cur_limits = max_valid;
-                       else
-                               cur_limits = file_count;
-               } else {
-                       if (file_count > max_valid)
-                               cur_limits = max_valid;
-                       else
-                               cur_limits = file_count;
-               }
-               /*
-                * only need to reset the LO_WAT_ALERT... the HI_WAT size is fixed,
-                * it doesn't change even if the swap file size shrinks or grows
-                */
-               macx_triggers(local_hi_water, limits[cur_limits].low_water, LO_WAT_ALERT, alert_port);
-       }
-       return KERN_SUCCESS;
-}
-
-void
-wait_on_paging_trigger(trigger_port)
-       mach_port_t     trigger_port;
-{
-       kern_return_t   result;
-       result = server_alert_loop(4096, trigger_port, MACH_MSG_OPTION_NONE);
-       if (result != KERN_SUCCESS) {
-            fprintf(stderr, "dynamic_pager: default pager alert failed\n");
-            exit(1);
-       }
-       exit(0);
+       closedir(dir);

 }
 
 }
 

-void
-paging_setup(flags, size, priority, low, high)
-       int     flags;
-       int     size;
-       int     priority;
-       int     low;
-       int     high;
-{
-       off_t           filesize = size;
-       char            subfile[512];
-       FILE            *file_ptr;
-       int             error;
-
-       file_count = 0;
-       sprintf(subfile, "%s%d", fileroot, file_count);
-       file_ptr = fopen(subfile, "w+");
-       fchmod(fileno(file_ptr), (mode_t)01600);
-       error = fcntl(fileno(file_ptr), F_SETSIZE, &filesize);
-       if(error) {
-       error = ftruncate(fileno(file_ptr), filesize);
-       }
-       fclose(file_ptr);
-        
-       macx_swapon(subfile, flags, size, priority);
-
-       if(hi_water) {
-               mach_msg_type_name_t    poly;
-
-               daemon(0,0);
-
-               if (mach_port_allocate(mach_task_self(), 
-                               MACH_PORT_RIGHT_RECEIVE, 
-                               &trigger_port) != KERN_SUCCESS)  {
-                       fprintf(stderr,"allocation of trigger port failed\n");
-                       exit(1);
-               }
-               /* create a send right on our local port */
-               mach_port_extract_right(mach_task_self(), trigger_port,
-                       MACH_MSG_TYPE_MAKE_SEND, &trigger_port, &poly);
-               macx_triggers(high, low, HI_WAT_ALERT, trigger_port);
-
-               if(low) {
-                       macx_triggers(high, low, LO_WAT_ALERT, trigger_port);
-               }
-               /* register control port for applications wishing to */
-               /* get backing store notifications or change dynamic */
-               /* pager settings. */
-               set_dp_control_port(mach_host_self(), trigger_port);
-               wait_on_paging_trigger(trigger_port); 
-       }
-       exit(0);
-}

 int
 main(int argc, char **argv)
 {
 int
 main(int argc, char **argv)
 {

-       extern char *optarg;
-       extern int optind;
-       char default_filename[] = "/private/var/vm/swapfile";

        int ch;
        int ch;

-       int variable_sized = 1;
+       static char tmp[1024];
+       struct statfs sfs;
+       char *q;
+       char fileroot[512];

 
        seteuid(getuid());
 
        seteuid(getuid());

-       strcpy(fileroot, default_filename);
-
-       limits[0].size = 20000000;
-       limits[0].low_water = 0;
-
-       hi_water = 0;
-       local_hi_water = 0;
+       fileroot[0] = '\0';

 
 

-
-       while ((ch = getopt(argc, argv, "F:L:H:S:P:O:")) != EOF) {
+       while ((ch = getopt(argc, argv, "F:")) != EOF) {

                switch((char)ch) {
 
                case 'F':
                        strncpy(fileroot, optarg, 500);
                        break;
 
                switch((char)ch) {
 
                case 'F':
                        strncpy(fileroot, optarg, 500);
                        break;
 

-               case 'L':
-                       variable_sized = 0;
-                       limits[0].low_water = atoi(optarg);
-                       break;
-               case 'H':
-                       variable_sized = 0;
-                       hi_water = atoi(optarg);
-                       break;
-               case 'S':
-                       variable_sized = 0;
-                       limits[0].size = atoi(optarg);
-                       break;
-               case 'P':
-                       priority = atoi(optarg);
-                       break;
-

                default:
                        (void)fprintf(stderr,
                default:
                        (void)fprintf(stderr,

-                           "usage: dynamic_pager [-F filename] [-L low water alert trigger] [-H high water alert trigger] [-S file size] [-P priority]\n");
-                       exit(1);
+                           "usage: dynamic_pager [-F filename]\n");
+                       exit(0);

                }
        }
 
                }
        }
 

-       if (variable_sized) {
-               static char tmp[1024];
-               struct statfs sfs;
-               char *q;
-               int  i;
-               int  mib[4];
-               size_t len;
-               unsigned int size;
-               u_int64_t  memsize;
-               u_int64_t  fs_limit;
-
-               /*
-                * if we get here, then none of the following options were specified... -L, H, or -S
-                * drop into a new mode that scales the size of the swap file based on how much free
-                * space is left on the volume being used for swap and the amount of physical ram 
-                * installed on the system...
-                * basically, we'll pick a maximum size that doesn't exceed the following limits...
-                *   1/4 the remaining free space of the swap volume 
-                *   the size of phsyical ram
-                *   MAXIMUM_SIZE - currently set to 1 Gbyte... 
-                * once we have the maximum, we'll create a list of sizes and low_water limits
-                * we'll start with 2 files of MINIMUM_SIZE - currently 64 Mbytes...
-                * subsequent entries will double in size up to the calculated maximum... the low_water
-                * limit will be the sum of the current file size and the previous file size for each entry...
-                * as we add or delete files, we'll use the current file_count as an index into this 
-                * table... if it's beyond the table size, we'll use the last entry
-                * the table entry will determine the size of the file to be created and the new low_water mark...
-                * the high_water mark is set to HI_WATER_DEFAULT which  must be smaller than MINIMUM_SIZE...
-                * currently it is set to 40,000,000 to match the size being requested by the application 
-                * monitoring low space conditions... having it set to the same size keeps us from creating
-                * an additional swap file when it really isn't necessary
-                */
-
-               /*
-                * get rid of the filename at the end of the swap file specification
-                * we only want the portion of the pathname that should already exist
-                */
-               strcpy(tmp, fileroot);
-               if (q = strrchr(tmp, '/'))
-                       *q = 0;
-
-               if (statfs(tmp, &sfs) != -1) {
-                       /*
-                        * limit the maximum size of a swap file to 1/4 the free
-                        * space available on the filesystem where the swap files
-                        * are to reside
-                        */
-                       fs_limit = ((u_int64_t)sfs.f_bfree * (u_int64_t)sfs.f_bsize) / 4;
-
-               } else {
-                       (void)fprintf(stderr, "usage: swap directory must exist\n"); 
-                       exit(1);
+       /*
+        * set vm.swapfileprefix if a fileroot was passed from the command
+        * line, otherwise get the value from the kernel
+        */
+       if (fileroot[0] != '\0') {
+               if (sysctlbyname("vm.swapfileprefix", NULL, 0, fileroot, sizeof(fileroot)) == -1) {
+                       perror("Failed to set swapfile name prefix");

                }
                }

-               mib[0] = CTL_HW;
-               mib[1] = HW_MEMSIZE;
-               len = sizeof(u_int64_t);
-
-               if (sysctl(mib, 2, &memsize, &len, NULL, 0) < 0) {
-                       /*
-                        * if the sysctl fails for some reason
-                        * use the starting size as the default
+       } else {
+               size_t fileroot_len = sizeof(fileroot);
+               if (sysctlbyname("vm.swapfileprefix", fileroot, &fileroot_len, NULL, 0) == -1) {
+                       perror("Failed to get swapfile name prefix");
+                       /*
+                        * can't continue without a fileroot

                         */
                         */

-                       memsize = MINIMUM_SIZE;
+                       return (0);

                }
                }

-               if (memsize > fs_limit)
-                       /*
-                        * clip based on filesystem space available
-                        */
-                       memsize = fs_limit;
+       }

 
 

-               /*
-                * further limit the maximum size of a swap file
-                */
-               if (memsize > MAXIMUM_SIZE)
-                       memsize = MAXIMUM_SIZE;
-               
-               size = MINIMUM_SIZE;
+       /*
+        * get rid of the filename at the end of the swap file specification
+        * we only want the portion of the pathname that should already exist
+        */
+       strcpy(tmp, fileroot);
+       if ((q = strrchr(tmp, '/')))
+               *q = 0;
+
+       /*
+        * Remove all files in the swap directory.
+        */
+       clean_swap_directory(tmp);

 
 

+       if (statfs(tmp, &sfs) == -1) {

                /*
                /*

-                * start small and work our way up to the maximum
-                * sized allowed... this way, we don't tie up too
-                * much disk space if we never do any real paging
+                * Setup the swap directory.

                 */
                 */

-               for (max_valid = 0, i = 0; i < MAX_LIMITS; i++) {
-                       limits[i].size = size;

 
 

-                       if (i == 0)
-                               limits[i].low_water = size * 2;
-                       else {
-                               if ((limits[i - 1].size / 2) > HI_WATER_DEFAULT)
-                                       limits[i].low_water = size + (limits[i - 1].size / 2);
-                               else
-                                       limits[i].low_water = size + limits[i - 1].size;
-                       }
-                       if (size >= memsize)
-                               break;
-                       
-                       if (i) {
-                               /*
-                                * make the first 2 files the same size
-                                */
-                               size = size * 2;
-                       }
-                       max_valid++;
+               if (mkdir(tmp, 0755) == -1) {
+                       (void)fprintf(stderr, "dynamic_pager: cannot create swap directory %s\n", tmp);

                }
                }

-               if (max_valid >= MAX_LIMITS)
-                       max_valid = MAX_LIMITS - 1;
-
-               hi_water = HI_WATER_DEFAULT;
-       }
-       local_hi_water = hi_water;
-
-       if((limits[0].low_water != 0) && (limits[0].low_water <= (limits[0].size + hi_water))) {
-               (void)fprintf(stderr,  "usage: low water trigger must be larger than size + hi_water\n"); 
-               exit(1);

        }
        }

-       argc -= optind;
-       argv += optind;

 
 

-       paging_setup(0, limits[0].size, priority, limits[0].low_water, hi_water);
+       chown(tmp, 0, 0);

 
        return (0);
 }
 
        return (0);
 }