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Diffstat (limited to 'mach-defpager/default_pager.c')
| -rw-r--r-- | mach-defpager/default_pager.c | 3921 |
1 files changed, 3921 insertions, 0 deletions
diff --git a/mach-defpager/default_pager.c b/mach-defpager/default_pager.c new file mode 100644 index 00000000..41c2768d --- /dev/null +++ b/mach-defpager/default_pager.c @@ -0,0 +1,3921 @@ +/* + * Mach Operating System + * Copyright (c) 1993-1989 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + * Default pager. Pages to paging partition. + * + * MUST BE ABLE TO ALLOCATE WIRED-DOWN MEMORY!!! + */ + +#include <mach.h> +#include <mach/message.h> +#include <mach/notify.h> +#include <mach/mig_errors.h> +#include <mach/thread_switch.h> +#include <mach/task_info.h> +#include <mach/default_pager_types.h> + +#include <cthreads.h> + +#include <device/device_types.h> +#include <device/device.h> + +#include <queue.h> +#include <wiring.h> + +#include <assert.h> +#include <stdio.h> + +#include <file_io.h> + +#include "default_pager_S.h" + +#define debug 0 + +extern void *kalloc(); + +static char my_name[] = "(default pager):"; + +static struct mutex printf_lock = MUTEX_INITIALIZER; + +#define dprintf(f, x...) \ + ({ mutex_lock (&printf_lock); printf (f , ##x); fflush (stdout); mutex_unlock (&printf_lock); }) +#define ddprintf(f, x...) ((void)0) + +/* + * parallel vs serial switch + */ +#define PARALLEL 1 + +#if 0 +#define CHECKSUM 1 +#endif + +#define USE_PRECIOUS 1 + +#define ptoa(p) ((p)*vm_page_size) +#define atop(a) ((a)/vm_page_size) + +/* + + */ +/* + * Bitmap allocation. + */ +typedef unsigned int bm_entry_t; +#define NB_BM 32 +#define BM_MASK 0xffffffff + +#define howmany(a,b) (((a) + (b) - 1)/(b)) + +/* + * Value to indicate no block assigned + */ +#define NO_BLOCK ((vm_offset_t)-1) + +/* + * 'Partition' structure for each paging area. + * Controls allocation of blocks within paging area. + */ +struct part { + struct mutex p_lock; /* for bitmap/free */ + vm_size_t total_size; /* total number of blocks */ + vm_size_t free; /* number of blocks free */ + unsigned int id; /* named lookup */ + bm_entry_t *bitmap; /* allocation map */ + boolean_t going_away; /* destroy attempt in progress */ + struct file_direct *file; /* file paged to */ +}; +typedef struct part *partition_t; + +struct { + struct mutex lock; + int n_partitions; + partition_t *partition_list;/* array, for quick mapping */ +} all_partitions; /* list of all such */ + +typedef unsigned char p_index_t; + +#define P_INDEX_INVALID ((p_index_t)-1) + +#define no_partition(x) ((x) == P_INDEX_INVALID) + +partition_t partition_of(x) + int x; +{ + if (x >= all_partitions.n_partitions || x < 0) + panic("partition_of x%x", x); + return all_partitions.partition_list[x]; +} + +void set_partition_of(x, p) + int x; + partition_t p; +{ + if (x >= all_partitions.n_partitions || x < 0) + panic("set_partition_of x%x", x); + all_partitions.partition_list[x] = p; +} + +/* + * Simple mapping from (file)NAME to id + * Saves space, filenames can be long. + */ +unsigned int +part_id(const unsigned char *name) +{ + register unsigned int len, id, xorid; + + len = strlen(name); + id = xorid = 0; + while (len--) { + xorid ^= *name; + id += *name++; + } + return (id << 8) | xorid; +} + +partition_init() +{ + mutex_init(&all_partitions.lock); + all_partitions.n_partitions = 0; +} + +static partition_t +new_partition (const char *name, struct file_direct *fdp, + int check_linux_signature) +{ + register partition_t part; + register vm_size_t size, bmsize; + vm_offset_t raddr; + mach_msg_type_number_t rsize; + int rc; + unsigned int id = part_id(name); + + mutex_lock(&all_partitions.lock); + { + unsigned int i; + for (i = 0; i < all_partitions.n_partitions; i++) + { + part = partition_of(i); + if (part && part->id == id) + { + printf ("(default pager): Already paging to partition %s!\n", + name); + mutex_unlock(&all_partitions.lock); + return 0; + } + } + } + mutex_unlock(&all_partitions.lock); + + size = atop(fdp->fd_size * fdp->fd_bsize); + bmsize = howmany(size, NB_BM) * sizeof(bm_entry_t); + + part = (partition_t) kalloc(sizeof(struct part)); + mutex_init(&part->p_lock); + part->total_size = size; + part->free = size; + part->id = id; + part->bitmap = (bm_entry_t *)kalloc(bmsize); + part->going_away= FALSE; + part->file = fdp; + + bzero((char *)part->bitmap, bmsize); + + if (check_linux_signature < 0) + { + if (check_linux_signature != -3) + printf("(default pager): " + "Paging to raw partition %s (%uk paging space)\n", + name, part->total_size * (vm_page_size / 1024)); + return part; + } + +#define LINUX_PAGE_SIZE 4096 /* size of pages in Linux swap partitions */ + rc = page_read_file_direct(part->file, + 0, LINUX_PAGE_SIZE, + &raddr, + &rsize); + if (rc) + panic("(default pager): cannot read first page of %s! rc=%#x\n", + name, rc); + while (rsize < LINUX_PAGE_SIZE) + { + /* Filesystem block size is smaller than page size, + so we must do several reads to get the whole page. */ + vm_address_t baddr, bsize; + rc = page_read_file_direct(part->file, + rsize, LINUX_PAGE_SIZE-rsize, + &baddr, + &bsize); + if (rc) + panic("(default pager): " + "cannot read first page of %s! rc=%#x at %#x\n", + name, rc, rsize); + + memcpy ((char *) raddr + rsize, (void *) baddr, bsize); + rsize += bsize; + vm_deallocate (mach_task_self (), baddr, bsize); + } + + if (!memcmp("SWAP-SPACE", (char *) raddr + LINUX_PAGE_SIZE-10, 10)) + { + /* The partition's first page has a Linux swap signature. + This means the beginning of the page contains a bitmap + of good pages, and all others are bad. */ + unsigned int i, j, bad, max; + int waste; + + printf("(default pager): Found Linux 2.0 swap signature in %s\n", + name); + + /* The first page, and the pages corresponding to the bits + occupied by the signature in the final 10 bytes of the page, + are always unavailable ("bad"). */ + *(u_int32_t *)raddr &= ~(u_int32_t) 1; + memset((char *) raddr + LINUX_PAGE_SIZE-10, 0, 10); + + max = LINUX_PAGE_SIZE / sizeof(u_int32_t); + if (max > (part->total_size + 31) / 32) + max = (part->total_size + 31) / 32; + + bad = 0; + for (i = 0; i < max; ++i) + { + u_int32_t bm = ((u_int32_t *) raddr)[i]; + if (bm == ~(u_int32_t) 0) + continue; + /* There are some zero bits in this word. */ + for (j = 0; j < 32; ++j) + if ((bm & (1 << j)) == 0) + { + unsigned int p = i*32 + j; + if (p >= part->total_size) + break; + ++bad; + part->bitmap[p / NB_BM] |= 1 << (p % NB_BM); + } + } + part->free -= bad; + + --bad; /* Don't complain about first page. */ + waste = part->total_size - (8 * (LINUX_PAGE_SIZE-10)); + if (waste > 0) + { + /* The wasted pages were already marked "bad". */ + bad -= waste; + if (bad > 0) + printf("\ +(default pager): Paging to %s, %dk swap-space (%dk bad, %dk wasted at end)\n", + name, + part->free * (LINUX_PAGE_SIZE / 1024), + bad * (LINUX_PAGE_SIZE / 1024), + waste * (LINUX_PAGE_SIZE / 1024)); + else + printf("\ +(default pager): Paging to %s, %dk swap-space (%dk wasted at end)\n", + name, + part->free * (LINUX_PAGE_SIZE / 1024), + waste * (LINUX_PAGE_SIZE / 1024)); + } + else if (bad > 0) + printf("\ +(default pager): Paging to %s, %dk swap-space (excludes %dk marked bad)\n", + name, + part->free * (LINUX_PAGE_SIZE / 1024), + bad * (LINUX_PAGE_SIZE / 1024)); + else + printf("\ +(default pager): Paging to %s, %dk swap-space\n", + name, + part->free * (LINUX_PAGE_SIZE / 1024)); + } + else if (!memcmp("SWAPSPACE2", + (char *) raddr + LINUX_PAGE_SIZE-10, 10)) + { + struct + { + u_int8_t bootbits[1024]; + u_int32_t version; + u_int32_t last_page; + u_int32_t nr_badpages; + u_int32_t padding[125]; + u_int32_t badpages[1]; + } *hdr = (void *) raddr; + + printf("\ +(default pager): Found Linux 2.2 swap signature (v%u) in %s...", + hdr->version, name); + + part->bitmap[0] |= 1; /* first page unusable */ + part->free--; + + switch (hdr->version) + { + default: + if (check_linux_signature) + { + printf ("version %u unknown! SKIPPING %s!\n", + hdr->version, + name); + vm_deallocate(mach_task_self(), raddr, rsize); + kfree(part->bitmap, bmsize); + kfree(part, sizeof *part); + return 0; + } + else + printf ("version %u unknown! IGNORING SIGNATURE PAGE!" + " %dk swap-space\n", + hdr->version, + part->free * (LINUX_PAGE_SIZE / 1024)); + break; + + case 1: + { + unsigned int waste, i; + if (hdr->last_page > part->total_size) + { + printf ("signature says %uk, partition has only %uk! ", + hdr->last_page * (LINUX_PAGE_SIZE / 1024), + part->total_size * (LINUX_PAGE_SIZE / 1024)); + waste = 0; + } + else + { + waste = part->total_size - hdr->last_page; + part->total_size = hdr->last_page; + part->free = part->total_size - 1; + } + for (i = 0; i < hdr->nr_badpages; ++i) + { + const u_int32_t bad = hdr->badpages[i]; + part->bitmap[bad / NB_BM] |= 1 << (bad % NB_BM); + part->free--; + } + printf ("%uk swap-space", + part->free * (LINUX_PAGE_SIZE / 1024)); + if (hdr->nr_badpages != 0) + printf (" (excludes %uk marked bad)", + hdr->nr_badpages * (LINUX_PAGE_SIZE / 1024)); + if (waste != 0) + printf (" (excludes %uk at end of partition)", + waste * (LINUX_PAGE_SIZE / 1024)); + printf ("\n"); + } + } + } + else if (check_linux_signature) + { + printf ("(default pager): " + "Cannot find Linux swap signature page! " + "SKIPPING %s (%uk partition)!", + name, part->total_size * (vm_page_size / 1024)); + kfree(part->bitmap, bmsize); + kfree(part, sizeof *part); + part = 0; + } + else + printf("(default pager): " + "Paging to raw partition %s (%uk paging space)\n", + name, part->total_size * (vm_page_size / 1024)); + + vm_deallocate(mach_task_self(), raddr, rsize); + + return part; +} + +/* + * Create a partition descriptor, + * add it to the list of all such. + * size is in BYTES. + */ +void +create_paging_partition(const char *name, + struct file_direct *fdp, int isa_file, + int linux_signature) +{ + register partition_t part; + + part = new_partition (name, fdp, linux_signature); + if (!part) + return; + + mutex_lock(&all_partitions.lock); + { + register int i; + + for (i = 0; i < all_partitions.n_partitions; i++) + if (partition_of(i) == 0) break; + + if (i == all_partitions.n_partitions) { + register partition_t *new_list, *old_list; + register int n; + + n = i ? (i<<1) : 2; + new_list = (partition_t *) + kalloc( n * sizeof(partition_t) ); + if (new_list == 0) no_paging_space(TRUE); + bzero(new_list, n*sizeof(partition_t)); + if (i) { + old_list = all_partitions.partition_list; + bcopy(old_list, new_list, i*sizeof(partition_t)); + } + all_partitions.partition_list = new_list; + all_partitions.n_partitions = n; + if (i) kfree(old_list, i*sizeof(partition_t)); + } + set_partition_of(i, part); + } + mutex_unlock(&all_partitions.lock); + +#if 0 + dprintf("%s Added paging %s %s\n", my_name, + (isa_file) ? "file" : "device", name); +#endif + overcommitted(TRUE, part->free); +} + +/* + * Choose the most appropriate default partition + * for an object of SIZE bytes. + * Return the partition locked, unless + * the object has no CUR_PARTition. + */ +p_index_t +choose_partition(size, cur_part) + unsigned int size; + register p_index_t cur_part; +{ + register partition_t part; + register boolean_t found = FALSE; + register int i; + + mutex_lock(&all_partitions.lock); + for (i = 0; i < all_partitions.n_partitions; i++) { + + /* the undesireable one ? */ + if (i == cur_part) + continue; + +ddprintf ("choose_partition(%x,%d,%d)\n",size,cur_part,i); + /* one that was removed ? */ + if ((part = partition_of(i)) == 0) + continue; + + /* one that is being removed ? */ + if (part->going_away) + continue; + + /* is it big enough ? */ + mutex_lock(&part->p_lock); + if (ptoa(part->free) >= size) { + if (cur_part != P_INDEX_INVALID) { + mutex_unlock(&all_partitions.lock); + return (p_index_t)i; + } else + found = TRUE; + } + mutex_unlock(&part->p_lock); + + if (found) break; + } + mutex_unlock(&all_partitions.lock); + return (found) ? (p_index_t)i : P_INDEX_INVALID; +} + +/* + * Allocate a page in a paging partition + * The partition is returned unlocked. + */ +vm_offset_t +pager_alloc_page(pindex, lock_it) + p_index_t pindex; +{ + register int bm_e; + register int bit; + register int limit; + register bm_entry_t *bm; + partition_t part; + static char here[] = "%spager_alloc_page"; + + if (no_partition(pindex)) + return (NO_BLOCK); +ddprintf ("pager_alloc_page(%d,%d)\n",pindex,lock_it); + part = partition_of(pindex); + + /* unlikely, but possible deadlock against destroy_partition */ + if (!part || part->going_away) + return (NO_BLOCK); + + if (lock_it) + mutex_lock(&part->p_lock); + + if (part->free == 0) { + /* out of paging space */ + mutex_unlock(&part->p_lock); + return (NO_BLOCK); + } + + limit = howmany(part->total_size, NB_BM); + bm = part->bitmap; + for (bm_e = 0; bm_e < limit; bm_e++, bm++) + if (*bm != BM_MASK) + break; + + if (bm_e == limit) + panic(here,my_name); + + /* + * Find and set the proper bit + */ + { + register bm_entry_t b = *bm; + + for (bit = 0; bit < NB_BM; bit++) + if ((b & (1<<bit)) == 0) + break; + if (bit == NB_BM) + panic(here,my_name); + + *bm = b | (1<<bit); + part->free--; + + } + + mutex_unlock(&part->p_lock); + + return (bm_e*NB_BM+bit); +} + +/* + * Deallocate a page in a paging partition + */ +void +pager_dealloc_page(pindex, page, lock_it) + p_index_t pindex; + register vm_offset_t page; +{ + register partition_t part; + register int bit, bm_e; + + /* be paranoid */ + if (no_partition(pindex)) + panic("%sdealloc_page",my_name); +ddprintf ("pager_dealloc_page(%d,%x,%d)\n",pindex,page,lock_it); + part = partition_of(pindex); + + if (page >= part->total_size) + panic("%sdealloc_page",my_name); + + bm_e = page / NB_BM; + bit = page % NB_BM; + + if (lock_it) + mutex_lock(&part->p_lock); + + part->bitmap[bm_e] &= ~(1<<bit); + part->free++; + + if (lock_it) + mutex_unlock(&part->p_lock); +} + +/* + + */ +/* + * Allocation info for each paging object. + * + * Most operations, even pager_write_offset and pager_put_checksum, + * just need a read lock. Higher-level considerations prevent + * conflicting operations on a single page. The lock really protects + * the underlying size and block map memory, so pager_extend needs a + * write lock. + * + * An object can now span multiple paging partitions. The allocation + * info we keep is a pair (offset,p_index) where the index is in the + * array of all partition ptrs, and the offset is partition-relative. + * Size wise we are doing ok fitting the pair into a single integer: + * the offset really is in pages so we have vm_page_size bits available + * for the partition index. + */ +#define DEBUG_READER_CONFLICTS 0 + +#if DEBUG_READER_CONFLICTS +int default_pager_read_conflicts = 0; +#endif + +union dp_map { + + struct { + unsigned int p_offset : 24, + p_index : 8; + } block; + + union dp_map *indirect; +}; +typedef union dp_map *dp_map_t; + +/* quick check for part==block==invalid */ +#define no_block(e) ((e).indirect == (dp_map_t)NO_BLOCK) +#define invalidate_block(e) ((e).indirect = (dp_map_t)NO_BLOCK) + +struct dpager { + struct mutex lock; /* lock for extending block map */ + /* XXX should be read-write lock */ +#if DEBUG_READER_CONFLICTS + int readers; + boolean_t writer; +#endif + dp_map_t map; /* block map */ + vm_size_t size; /* size of paging object, in pages */ + vm_size_t limit; /* limit (bytes) allowed to grow to */ + p_index_t cur_partition; +#ifdef CHECKSUM + vm_offset_t *checksum; /* checksum - parallel to block map */ +#define NO_CHECKSUM ((vm_offset_t)-1) +#endif /* CHECKSUM */ +}; +typedef struct dpager *dpager_t; + +/* + * A paging object uses either a one- or a two-level map of offsets + * into a paging partition. + */ +#define PAGEMAP_ENTRIES 64 + /* number of pages in a second-level map */ +#define PAGEMAP_SIZE(npgs) ((npgs)*sizeof(vm_offset_t)) + +#define INDIRECT_PAGEMAP_ENTRIES(npgs) \ + ((((npgs)-1)/PAGEMAP_ENTRIES) + 1) +#define INDIRECT_PAGEMAP_SIZE(npgs) \ + (INDIRECT_PAGEMAP_ENTRIES(npgs) * sizeof(vm_offset_t *)) +#define INDIRECT_PAGEMAP(size) \ + (size > PAGEMAP_ENTRIES) + +#define ROUNDUP_TO_PAGEMAP(npgs) \ + (((npgs) + PAGEMAP_ENTRIES - 1) & ~(PAGEMAP_ENTRIES - 1)) + +/* + * Object sizes are rounded up to the next power of 2, + * unless they are bigger than a given maximum size. + */ +vm_size_t max_doubled_size = 4 * 1024 * 1024; /* 4 meg */ + +/* + * Attach a new paging object to a paging partition + */ +void +pager_alloc(pager, part, size) + register dpager_t pager; + p_index_t part; + register vm_size_t size; /* in BYTES */ +{ + register int i; + register dp_map_t mapptr, emapptr; + + mutex_init(&pager->lock); +#if DEBUG_READER_CONFLICTS + pager->readers = 0; + pager->writer = FALSE; +#endif + pager->cur_partition = part; + + /* + * Convert byte size to number of pages, then increase to the nearest + * power of 2. + */ + size = atop(size); + if (size <= atop(max_doubled_size)) { + i = 1; + while (i < size) + i <<= 1; + size = i; + } else + size = ROUNDUP_TO_PAGEMAP(size); + + /* + * Allocate and initialize the block map + */ + { + register vm_size_t alloc_size; + dp_map_t init_value; + + if (INDIRECT_PAGEMAP(size)) { + alloc_size = INDIRECT_PAGEMAP_SIZE(size); + init_value = (dp_map_t)0; + } else { + alloc_size = PAGEMAP_SIZE(size); + init_value = (dp_map_t)NO_BLOCK; + } + + mapptr = (dp_map_t) kalloc(alloc_size); + for (emapptr = &mapptr[(alloc_size-1) / sizeof(vm_offset_t)]; + emapptr >= mapptr; + emapptr--) + emapptr->indirect = init_value; + + } + pager->map = mapptr; + pager->size = size; + pager->limit = (vm_size_t)-1; + +#ifdef CHECKSUM + if (INDIRECT_PAGEMAP(size)) { + mapptr = (vm_offset_t *) + kalloc(INDIRECT_PAGEMAP_SIZE(size)); + for (i = INDIRECT_PAGEMAP_ENTRIES(size); --i >= 0;) + mapptr[i] = 0; + } else { + mapptr = (vm_offset_t *) kalloc(PAGEMAP_SIZE(size)); + for (i = 0; i < size; i++) + mapptr[i] = NO_CHECKSUM; + } + pager->checksum = mapptr; +#endif /* CHECKSUM */ +} + +/* + * Return size (in bytes) of space actually allocated to this pager. + * The pager is read-locked. + */ + +vm_size_t +pager_allocated(pager) + register dpager_t pager; +{ + vm_size_t size; + register dp_map_t map, emap; + vm_size_t asize; + + size = pager->size; /* in pages */ + asize = 0; /* allocated, in pages */ + map = pager->map; + + if (INDIRECT_PAGEMAP(size)) { + for (emap = &map[INDIRECT_PAGEMAP_ENTRIES(size)]; + map < emap; map++) { + + register dp_map_t map2, emap2; + + if ((map2 = map->indirect) == 0) + continue; + + for (emap2 = &map2[PAGEMAP_ENTRIES]; + map2 < emap2; map2++) + if ( ! no_block(*map2) ) + asize++; + + } + } else { + for (emap = &map[size]; map < emap; map++) + if ( ! no_block(*map) ) + asize++; + } + + return ptoa(asize); +} + +/* + * Find offsets (in the object) of pages actually allocated to this pager. + * Returns the number of allocated pages, whether or not they all fit. + * The pager is read-locked. + */ + +unsigned int +pager_pages(pager, pages, numpages) + dpager_t pager; + register default_pager_page_t *pages; + unsigned int numpages; +{ + vm_size_t size; + dp_map_t map, emap; + unsigned int actual; + vm_offset_t offset; + + size = pager->size; /* in pages */ + map = pager->map; + actual = 0; + offset = 0; + + if (INDIRECT_PAGEMAP(size)) { + for (emap = &map[INDIRECT_PAGEMAP_ENTRIES(size)]; + map < emap; map++) { + + register dp_map_t map2, emap2; + + if ((map2 = map->indirect) == 0) { + offset += vm_page_size * PAGEMAP_ENTRIES; + continue; + } + for (emap2 = &map2[PAGEMAP_ENTRIES]; + map2 < emap2; map2++) + if ( ! no_block(*map2) ) { + if (actual++ < numpages) + pages++->dpp_offset = offset; + } + offset += vm_page_size; + } + } else { + for (emap = &map[size]; map < emap; map++) + if ( ! no_block(*map) ) { + if (actual++ < numpages) + pages++->dpp_offset = offset; + } + offset += vm_page_size; + } + return actual; +} + +/* + * Extend the map for a paging object. + * + * XXX This implementation can allocate an arbitrary large amount + * of wired memory when extending a big block map. Because vm-privileged + * threads call pager_extend, this can crash the system by exhausting + * system memory. + */ +void +pager_extend(pager, new_size) + register dpager_t pager; + register vm_size_t new_size; /* in pages */ +{ + register dp_map_t new_mapptr; + register dp_map_t old_mapptr; + register int i; + register vm_size_t old_size; + + mutex_lock(&pager->lock); /* XXX lock_write */ +#if DEBUG_READER_CONFLICTS + pager->writer = TRUE; +#endif + /* + * Double current size until we cover new size. + * If object is 'too big' just use new size. + */ + old_size = pager->size; + + if (new_size <= atop(max_doubled_size)) { + i = old_size; + while (i < new_size) + i <<= 1; + new_size = i; + } else + new_size = ROUNDUP_TO_PAGEMAP(new_size); + + if (INDIRECT_PAGEMAP(old_size)) { + /* + * Pager already uses two levels. Allocate + * a larger indirect block. + */ + new_mapptr = (dp_map_t) + kalloc(INDIRECT_PAGEMAP_SIZE(new_size)); + old_mapptr = pager->map; + for (i = 0; i < INDIRECT_PAGEMAP_ENTRIES(old_size); i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < INDIRECT_PAGEMAP_ENTRIES(new_size); i++) + new_mapptr[i].indirect = (dp_map_t)0; + kfree((char *)old_mapptr, INDIRECT_PAGEMAP_SIZE(old_size)); + pager->map = new_mapptr; + pager->size = new_size; +#ifdef CHECKSUM + new_mapptr = (vm_offset_t *) + kalloc(INDIRECT_PAGEMAP_SIZE(new_size)); + old_mapptr = pager->checksum; + for (i = 0; i < INDIRECT_PAGEMAP_ENTRIES(old_size); i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < INDIRECT_PAGEMAP_ENTRIES(new_size); i++) + new_mapptr[i] = 0; + kfree((char *)old_mapptr, INDIRECT_PAGEMAP_SIZE(old_size)); + pager->checksum = new_mapptr; +#endif /* CHECKSUM */ +#if DEBUG_READER_CONFLICTS + pager->writer = FALSE; +#endif + mutex_unlock(&pager->lock); +#if 0 + ddprintf ("pager_extend 1 mapptr %x [3b] = %x\n", new_mapptr, + new_mapptr[0x3b]); + if (new_mapptr[0x3b].indirect > 0x10000 + && new_mapptr[0x3b].indirect != NO_BLOCK) + panic ("debug panic"); +#endif + return; + } + + if (INDIRECT_PAGEMAP(new_size)) { + /* + * Changing from direct map to indirect map. + * Allocate both indirect and direct map blocks, + * since second-level (direct) block must be + * full size (PAGEMAP_SIZE(PAGEMAP_ENTRIES)). + */ + + /* + * Allocate new second-level map first. + */ + new_mapptr = (dp_map_t) kalloc(PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + old_mapptr = pager->map; + for (i = 0; i < old_size; i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < PAGEMAP_ENTRIES; i++) + invalidate_block(new_mapptr[i]); + kfree((char *)old_mapptr, PAGEMAP_SIZE(old_size)); + old_mapptr = new_mapptr; + +#if 0 + ddprintf ("pager_extend 2 mapptr %x [3b] = %x\n", new_mapptr, + new_mapptr[0x3b]); + if (new_mapptr[0x3b].indirect > 0x10000 + && new_mapptr[0x3b].indirect != NO_BLOCK) + panic ("debug panic"); +#endif + + /* + * Now allocate indirect map. + */ + new_mapptr = (dp_map_t) + kalloc(INDIRECT_PAGEMAP_SIZE(new_size)); + new_mapptr[0].indirect = old_mapptr; + for (i = 1; i < INDIRECT_PAGEMAP_ENTRIES(new_size); i++) + new_mapptr[i].indirect = 0; + pager->map = new_mapptr; + pager->size = new_size; +#ifdef CHECKSUM + /* + * Allocate new second-level map first. + */ + new_mapptr = (vm_offset_t *)kalloc(PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + old_mapptr = pager->checksum; + for (i = 0; i < old_size; i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < PAGEMAP_ENTRIES; i++) + new_mapptr[i] = NO_CHECKSUM; + kfree((char *)old_mapptr, PAGEMAP_SIZE(old_size)); + old_mapptr = new_mapptr; + + /* + * Now allocate indirect map. + */ + new_mapptr = (vm_offset_t *) + kalloc(INDIRECT_PAGEMAP_SIZE(new_size)); + new_mapptr[0] = (vm_offset_t) old_mapptr; + for (i = 1; i < INDIRECT_PAGEMAP_ENTRIES(new_size); i++) + new_mapptr[i] = 0; + pager->checksum = new_mapptr; +#endif /* CHECKSUM */ +#if DEBUG_READER_CONFLICTS + pager->writer = FALSE; +#endif + mutex_unlock(&pager->lock); + return; + } + /* + * Enlarging a direct block. + */ + new_mapptr = (dp_map_t) kalloc(PAGEMAP_SIZE(new_size)); + old_mapptr = pager->map; + for (i = 0; i < old_size; i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < new_size; i++) + invalidate_block(new_mapptr[i]); + kfree((char *)old_mapptr, PAGEMAP_SIZE(old_size)); + pager->map = new_mapptr; + pager->size = new_size; +#ifdef CHECKSUM + new_mapptr = (vm_offset_t *) + kalloc(PAGEMAP_SIZE(new_size)); + old_mapptr = pager->checksum; + for (i = 0; i < old_size; i++) + new_mapptr[i] = old_mapptr[i]; + for (; i < new_size; i++) + new_mapptr[i] = NO_CHECKSUM; + kfree((char *)old_mapptr, PAGEMAP_SIZE(old_size)); + pager->checksum = new_mapptr; +#endif /* CHECKSUM */ +#if DEBUG_READER_CONFLICTS + pager->writer = FALSE; +#endif + mutex_unlock(&pager->lock); +} + +/* Truncate a memory object. First, any pages between the new size + and the (larger) old size are deallocated. Then, the size of + the pagemap may be reduced, an indirect map may be turned into + a direct map. + + The pager must be locked by the caller. */ +static void +pager_truncate(dpager_t pager, vm_size_t new_size) /* in pages */ +{ + dp_map_t new_mapptr; + dp_map_t old_mapptr; + int i; + vm_size_t old_size; + + /* This deallocates the pages necessary to truncate a direct map + previously of size NEW_SIZE to the smaller size OLD_SIZE. */ + inline void dealloc_direct (dp_map_t mapptr, + vm_size_t old_size, vm_size_t new_size) + { + vm_size_t i; + for (i = new_size; i < old_size; ++i) + { + const union dp_map entry = mapptr[i]; + pager_dealloc_page(entry.block.p_index, entry.block.p_offset, + TRUE); + invalidate_block(mapptr[i]); + } + } + + old_size = pager->size; + + if (INDIRECT_PAGEMAP(old_size)) + { + /* First handle the entire second-levels blocks that are being freed. */ + for (i = INDIRECT_PAGEMAP_ENTRIES(new_size); + i < INDIRECT_PAGEMAP_ENTRIES(old_size); + ++i) + { + const dp_map_t mapptr = pager->map[i].indirect; + pager->map[i].indirect = (dp_map_t)0; + dealloc_direct (mapptr, PAGEMAP_ENTRIES, 0); + kfree ((char *)mapptr, PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + } + + /* Now truncate what's now the final nonempty direct block. */ + dealloc_direct (pager->map[(new_size - 1) / PAGEMAP_ENTRIES].indirect, + old_size & (PAGEMAP_ENTRIES - 1), + new_size & (PAGEMAP_ENTRIES - 1)); + + if (INDIRECT_PAGEMAP (new_size)) + { + if (INDIRECT_PAGEMAP_SIZE (new_size) >= vm_page_size) + /* XXX we know how kalloc.c works; avoid copying. */ + kfree ((char *) round_page ((vm_address_t) pager->map + + INDIRECT_PAGEMAP_SIZE (new_size)), + round_page (INDIRECT_PAGEMAP_SIZE (old_size)) + - round_page (INDIRECT_PAGEMAP_SIZE (new_size))); + else + { + const dp_map_t old_mapptr = pager->map; + pager->map = (dp_map_t) kalloc (INDIRECT_PAGEMAP_SIZE(new_size)); + memcpy (pager->map, old_mapptr, INDIRECT_PAGEMAP_SIZE(old_size)); + kfree ((char *) old_mapptr, INDIRECT_PAGEMAP_SIZE (old_size)); + } + } + else + { + /* We are truncating to a size small enough that it goes to using + a one-level map. We already have that map, as the first and only + nonempty element in our indirect map. */ + const dp_map_t mapptr = pager->map[0].indirect; + kfree((char *)pager->map, INDIRECT_PAGEMAP_SIZE(old_size)); + pager->map = mapptr; + old_size = PAGEMAP_ENTRIES; + } + } + + if (new_size == 0) + new_size = 1; + + if (! INDIRECT_PAGEMAP(old_size)) + { + /* First deallocate pages in the truncated region. */ + dealloc_direct (pager->map, old_size, new_size); + /* Now reduce the size of the direct map itself. We don't bother + with kalloc/kfree if it's not shrinking enough that kalloc.c + would actually use less. */ + if (PAGEMAP_SIZE (new_size) <= PAGEMAP_SIZE (old_size) / 2) + { + const dp_map_t old_mapptr = pager->map; + pager->map = (dp_map_t) kalloc (PAGEMAP_SIZE (new_size)); + memcpy (pager->map, old_mapptr, PAGEMAP_SIZE (old_size)); + kfree ((char *) old_mapptr, PAGEMAP_SIZE (old_size)); + } + } + + pager->size = new_size; + +#ifdef CHECKSUM +#error write me +#endif /* CHECKSUM */ +} + + +/* + * Given an offset within a paging object, find the + * corresponding block within the paging partition. + * Return NO_BLOCK if none allocated. + */ +union dp_map +pager_read_offset(pager, offset) + register dpager_t pager; + vm_offset_t offset; +{ + register vm_offset_t f_page; + union dp_map pager_offset; + + f_page = atop(offset); + +#if DEBUG_READER_CONFLICTS + if (pager->readers > 0) + default_pager_read_conflicts++; /* would have proceeded with + read/write lock */ +#endif + mutex_lock(&pager->lock); /* XXX lock_read */ +#if DEBUG_READER_CONFLICTS + pager->readers++; +#endif + if (f_page >= pager->size) + { + ddprintf ("%spager_read_offset pager %x: bad page %d >= size %d", + my_name, pager, f_page, pager->size); + mutex_unlock(&pager->lock); + return (union dp_map) (union dp_map *) NO_BLOCK; +#if 0 + panic("%spager_read_offset",my_name); +#endif + } + + if (INDIRECT_PAGEMAP(pager->size)) { + register dp_map_t mapptr; + + mapptr = pager->map[f_page/PAGEMAP_ENTRIES].indirect; + if (mapptr == 0) + invalidate_block(pager_offset); + else + pager_offset = mapptr[f_page%PAGEMAP_ENTRIES]; + } + else { + pager_offset = pager->map[f_page]; + } + +#if DEBUG_READER_CONFLICTS + pager->readers--; +#endif + mutex_unlock(&pager->lock); + return (pager_offset); +} + +#if USE_PRECIOUS +/* + * Release a single disk block. + */ +pager_release_offset(pager, offset) + register dpager_t pager; + vm_offset_t offset; +{ + register union dp_map entry; + + offset = atop(offset); + + mutex_lock(&pager->lock); /* XXX lock_read */ + + if (INDIRECT_PAGEMAP(pager->size)) { + register dp_map_t mapptr; + + mapptr = pager->map[offset / PAGEMAP_ENTRIES].indirect; + entry = mapptr[offset % PAGEMAP_ENTRIES]; + invalidate_block(mapptr[offset % PAGEMAP_ENTRIES]); + } else { + entry = pager->map[offset]; + invalidate_block(pager->map[offset]); + } + + mutex_unlock(&pager->lock); + + pager_dealloc_page(entry.block.p_index, entry.block.p_offset, TRUE); +} +#endif /*USE_PRECIOUS*/ + + +/* + * Move a page from one partition to another + * New partition is locked, old partition is + * locked unless LOCK_OLD sez otherwise. + */ +union dp_map +pager_move_page(block) + union dp_map block; +{ + partition_t old_part, new_part; + p_index_t old_pindex, new_pindex; + union dp_map ret; + vm_size_t size; + vm_offset_t raddr, offset, new_offset; + kern_return_t rc; + static char here[] = "%spager_move_page"; + + old_pindex = block.block.p_index; + invalidate_block(ret); + + /* See if we have room to put it anywhere else */ + new_pindex = choose_partition( ptoa(1), old_pindex); + if (no_partition(new_pindex)) + return ret; + + /* this unlocks the new partition */ + new_offset = pager_alloc_page(new_pindex, FALSE); + if (new_offset == NO_BLOCK) + panic(here,my_name); + + /* + * Got the resources, now move the data + */ +ddprintf ("pager_move_page(%x,%d,%d)\n",block.block.p_offset,old_pindex,new_pindex); + old_part = partition_of(old_pindex); + offset = ptoa(block.block.p_offset); + rc = page_read_file_direct (old_part->file, + offset, + vm_page_size, + &raddr, + &size); + if (rc != 0) + panic(here,my_name); + + /* release old */ + pager_dealloc_page(old_pindex, block.block.p_offset, FALSE); + + new_part = partition_of(new_pindex); + offset = ptoa(new_offset); + rc = page_write_file_direct (new_part->file, + offset, + raddr, + size, + &size); + if (rc != 0) + panic(here,my_name); + + (void) vm_deallocate( mach_task_self(), raddr, size); + + ret.block.p_offset = new_offset; + ret.block.p_index = new_pindex; + + return ret; +} + +#ifdef CHECKSUM +/* + * Return the checksum for a block. + */ +int +pager_get_checksum(pager, offset) + register dpager_t pager; + vm_offset_t offset; +{ + register vm_offset_t f_page; + int checksum; + + f_page = atop(offset); + + mutex_lock(&pager->lock); /* XXX lock_read */ + if (f_page >= pager->size) + panic("%spager_get_checksum",my_name); + + if (INDIRECT_PAGEMAP(pager->size)) { + register vm_offset_t *mapptr; + + mapptr = (vm_offset_t *)pager->checksum[f_page/PAGEMAP_ENTRIES]; + if (mapptr == 0) + checksum = NO_CHECKSUM; + else + checksum = mapptr[f_page%PAGEMAP_ENTRIES]; + } + else { + checksum = pager->checksum[f_page]; + } + + mutex_unlock(&pager->lock); + return (checksum); +} + +/* + * Remember the checksum for a block. + */ +int +pager_put_checksum(pager, offset, checksum) + register dpager_t pager; + vm_offset_t offset; + int checksum; +{ + register vm_offset_t f_page; + static char here[] = "%spager_put_checksum"; + + f_page = atop(offset); + + mutex_lock(&pager->lock); /* XXX lock_read */ + if (f_page >= pager->size) + panic(here,my_name); + + if (INDIRECT_PAGEMAP(pager->size)) { + register vm_offset_t *mapptr; + + mapptr = (vm_offset_t *)pager->checksum[f_page/PAGEMAP_ENTRIES]; + if (mapptr == 0) + panic(here,my_name); + + mapptr[f_page%PAGEMAP_ENTRIES] = checksum; + } + else { + pager->checksum[f_page] = checksum; + } + mutex_unlock(&pager->lock); +} + +/* + * Compute a checksum - XOR each 32-bit word. + */ +int +compute_checksum(addr, size) + vm_offset_t addr; + vm_size_t size; +{ + register int checksum = NO_CHECKSUM; + register int *ptr; + register int count; + + ptr = (int *)addr; + count = size / sizeof(int); + + while (--count >= 0) + checksum ^= *ptr++; + + return (checksum); +} +#endif /* CHECKSUM */ + +/* + * Given an offset within a paging object, find the + * corresponding block within the paging partition. + * Allocate a new block if necessary. + * + * WARNING: paging objects apparently may be extended + * without notice! + */ +union dp_map +pager_write_offset(pager, offset) + register dpager_t pager; + vm_offset_t offset; +{ + register vm_offset_t f_page; + register dp_map_t mapptr; + register union dp_map block; + + invalidate_block(block); + + f_page = atop(offset); + +#if DEBUG_READER_CONFLICTS + if (pager->readers > 0) + default_pager_read_conflicts++; /* would have proceeded with + read/write lock */ +#endif + mutex_lock(&pager->lock); /* XXX lock_read */ +#if DEBUG_READER_CONFLICTS + pager->readers++; +#endif + + /* Catch the case where we had no initial fit partition + for this object, but one was added later on */ + if (no_partition(pager->cur_partition)) { + p_index_t new_part; + vm_size_t size; + + size = (f_page > pager->size) ? f_page : pager->size; + new_part = choose_partition(ptoa(size), P_INDEX_INVALID); + if (no_partition(new_part)) + new_part = choose_partition(ptoa(1), P_INDEX_INVALID); + if (no_partition(new_part)) + /* give up right now to avoid confusion */ + goto out; + else + pager->cur_partition = new_part; + } + + while (f_page >= pager->size) { + ddprintf ("pager_write_offset: extending: %x %x\n", f_page, pager->size); + + /* + * Paging object must be extended. + * Remember that offset is 0-based, but size is 1-based. + */ +#if DEBUG_READER_CONFLICTS + pager->readers--; +#endif + mutex_unlock(&pager->lock); + pager_extend(pager, f_page + 1); +#if DEBUG_READER_CONFLICTS + if (pager->readers > 0) + default_pager_read_conflicts++; /* would have proceeded with + read/write lock */ +#endif + mutex_lock(&pager->lock); /* XXX lock_read */ +#if DEBUG_READER_CONFLICTS + pager->readers++; +#endif + ddprintf ("pager_write_offset: done extending: %x %x\n", f_page, pager->size); + } + + if (INDIRECT_PAGEMAP(pager->size)) { + ddprintf ("pager_write_offset: indirect\n"); + mapptr = pager->map[f_page/PAGEMAP_ENTRIES].indirect; + if (mapptr == 0) { + /* + * Allocate the indirect block + */ + register int i; + ddprintf ("pager_write_offset: allocating indirect\n"); + + mapptr = (dp_map_t) kalloc(PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + if (mapptr == 0) { + /* out of space! */ + no_paging_space(TRUE); + goto out; + } + pager->map[f_page/PAGEMAP_ENTRIES].indirect = mapptr; + for (i = 0; i < PAGEMAP_ENTRIES; i++) + invalidate_block(mapptr[i]); +#ifdef CHECKSUM + { + register vm_offset_t *cksumptr; + register int j; + + cksumptr = (vm_offset_t *) + kalloc(PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + if (cksumptr == 0) { + /* out of space! */ + no_paging_space(TRUE); + goto out; + } + pager->checksum[f_page/PAGEMAP_ENTRIES] + = (vm_offset_t)cksumptr; + for (j = 0; j < PAGEMAP_ENTRIES; j++) + cksumptr[j] = NO_CHECKSUM; + } +#endif /* CHECKSUM */ + } + f_page %= PAGEMAP_ENTRIES; + } + else { + mapptr = pager->map; + } + + block = mapptr[f_page]; + ddprintf ("pager_write_offset: block starts as %x[%x] %x\n", mapptr, f_page, block); + if (no_block(block)) { + vm_offset_t off; + + /* get room now */ + off = pager_alloc_page(pager->cur_partition, TRUE); + if (off == NO_BLOCK) { + /* + * Before giving up, try all other partitions. + */ + p_index_t new_part; + + ddprintf ("pager_write_offset: could not allocate block\n"); + /* returns it locked (if any one is non-full) */ + new_part = choose_partition( ptoa(1), pager->cur_partition); + if ( ! no_partition(new_part) ) { + +#if debug +dprintf("%s partition %x filled,", my_name, pager->cur_partition); +dprintf("extending object %x (size %x) to %x.\n", + pager, pager->size, new_part); +#endif + + /* this one tastes better */ + pager->cur_partition = new_part; + + /* this unlocks the partition too */ + off = pager_alloc_page(pager->cur_partition, FALSE); + + } + + if (off == NO_BLOCK) { + /* + * Oh well. + */ + overcommitted(FALSE, 1); + goto out; + } + ddprintf ("pager_write_offset: decided to allocate block\n"); + } + block.block.p_offset = off; + block.block.p_index = pager->cur_partition; + mapptr[f_page] = block; + ddprintf ("pager_write_offset: mapptr %x [3b] = %x\n", mapptr, + mapptr[0x3b]); + ddprintf ("pager_write_offset: block is finally %x\n", block); + } + +out: + +#if DEBUG_READER_CONFLICTS + pager->readers--; +#endif + mutex_unlock(&pager->lock); + return (block); +} + +/* + * Deallocate all of the blocks belonging to a paging object. + * No locking needed because no other operations can be in progress. + */ +void +pager_dealloc(pager) + register dpager_t pager; +{ + register int i, j; + register dp_map_t mapptr; + register union dp_map block; + + if (INDIRECT_PAGEMAP(pager->size)) { + for (i = INDIRECT_PAGEMAP_ENTRIES(pager->size); --i >= 0; ) { + mapptr = pager->map[i].indirect; + if (mapptr != 0) { + for (j = 0; j < PAGEMAP_ENTRIES; j++) { + block = mapptr[j]; + if ( ! no_block(block) ) + pager_dealloc_page(block.block.p_index, + block.block.p_offset, TRUE); + } + kfree((char *)mapptr, PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + } + } + kfree((char *)pager->map, INDIRECT_PAGEMAP_SIZE(pager->size)); +#ifdef CHECKSUM + for (i = INDIRECT_PAGEMAP_ENTRIES(pager->size); --i >= 0; ) { + mapptr = (vm_offset_t *)pager->checksum[i]; + if (mapptr) { + kfree((char *)mapptr, PAGEMAP_SIZE(PAGEMAP_ENTRIES)); + } + } + kfree((char *)pager->checksum, + INDIRECT_PAGEMAP_SIZE(pager->size)); +#endif /* CHECKSUM */ + } + else { + mapptr = pager->map; + for (i = 0; i < pager->size; i++ ) { + block = mapptr[i]; + if ( ! no_block(block) ) + pager_dealloc_page(block.block.p_index, + block.block.p_offset, TRUE); + } + kfree((char *)pager->map, PAGEMAP_SIZE(pager->size)); +#ifdef CHECKSUM + kfree((char *)pager->checksum, PAGEMAP_SIZE(pager->size)); +#endif /* CHECKSUM */ + } +} + +/* + * Move all the pages of a PAGER that live in a + * partition PINDEX somewhere else. + * Pager should be write-locked, partition too. + * Returns FALSE if it could not do it, but + * some pages might have been moved nonetheless. + */ +boolean_t +pager_realloc(pager, pindex) + register dpager_t pager; + p_index_t pindex; +{ + register dp_map_t map, emap; + vm_size_t size; + union dp_map block; + + size = pager->size; /* in pages */ + map = pager->map; + + if (INDIRECT_PAGEMAP(size)) { + for (emap = &map[INDIRECT_PAGEMAP_ENTRIES(size)]; + map < emap; map++) { + + register dp_map_t map2, emap2; + + if ((map2 = map->indirect) == 0) + continue; + + for (emap2 = &map2[PAGEMAP_ENTRIES]; + map2 < emap2; map2++) + if ( map2->block.p_index == pindex) { + + block = pager_move_page(*map2); + if (!no_block(block)) + *map2 = block; + else + return FALSE; + } + + } + goto ok; + } + + /* A small one */ + for (emap = &map[size]; map < emap; map++) + if (map->block.p_index == pindex) { + block = pager_move_page(*map); + if (!no_block(block)) + *map = block; + else + return FALSE; + } +ok: + pager->cur_partition = choose_partition(0, P_INDEX_INVALID); + return TRUE; +} + +/* + + */ + +/* + * Read/write routines. + */ +#define PAGER_SUCCESS 0 +#define PAGER_ABSENT 1 +#define PAGER_ERROR 2 + +/* + * Read data from a default pager. Addr is the address of a buffer + * to fill. Out_addr returns the buffer that contains the data; + * if it is different from <addr>, it must be deallocated after use. + */ +int +default_read(ds, addr, size, offset, out_addr, deallocate, external) + register dpager_t ds; + vm_offset_t addr; /* pointer to block to fill */ + register vm_size_t size; + register vm_offset_t offset; + vm_offset_t *out_addr; + /* returns pointer to data */ + boolean_t deallocate; + boolean_t external; +{ + register union dp_map block; + vm_offset_t raddr; + vm_size_t rsize; + register int rc; + boolean_t first_time; + register partition_t part; +#ifdef CHECKSUM + vm_size_t original_size = size; +#endif /* CHECKSUM */ + vm_offset_t original_offset = offset; + + /* + * Find the block in the paging partition + */ + block = pager_read_offset(ds, offset); + if ( no_block(block) ) { + if (external) { + /* + * An external object is requesting unswapped data, + * zero fill the page and return. + */ + bzero((char *) addr, vm_page_size); + *out_addr = addr; + return (PAGER_SUCCESS); + } + return (PAGER_ABSENT); + } + + /* + * Read it, trying for the entire page. + */ + offset = ptoa(block.block.p_offset); +ddprintf ("default_read(%x,%x,%x,%d)\n",addr,size,offset,block.block.p_index); + part = partition_of(block.block.p_index); + first_time = TRUE; + *out_addr = addr; + + do { + rc = page_read_file_direct(part->file, + offset, + size, + &raddr, + &rsize); + if (rc != 0) + return (PAGER_ERROR); + + /* + * If we got the entire page on the first read, return it. + */ + if (first_time && rsize == size) { + *out_addr = raddr; + break; + } + /* + * Otherwise, copy the data into the + * buffer we were passed, and try for + * the next piece. + */ + first_time = FALSE; + bcopy((char *)raddr, (char *)addr, rsize); + addr += rsize; + offset += rsize; + size -= rsize; + } while (size != 0); + +#if USE_PRECIOUS + if (deallocate) + pager_release_offset(ds, original_offset); +#endif /*USE_PRECIOUS*/ + +#ifdef CHECKSUM + { + int write_checksum, + read_checksum; + + write_checksum = pager_get_checksum(ds, original_offset); + read_checksum = compute_checksum(*out_addr, original_size); + if (write_checksum != read_checksum) { + panic( + "PAGER CHECKSUM ERROR: offset 0x%x, written 0x%x, read 0x%x", + original_offset, write_checksum, read_checksum); + } + } +#endif /* CHECKSUM */ + return (PAGER_SUCCESS); +} + +int +default_write(ds, addr, size, offset) + register dpager_t ds; + register vm_offset_t addr; + register vm_size_t size; + register vm_offset_t offset; +{ + register union dp_map block; + partition_t part; + vm_size_t wsize; + register int rc; + + ddprintf ("default_write: pager offset %x\n", offset); + + /* + * Find block in paging partition + */ + block = pager_write_offset(ds, offset); + if ( no_block(block) ) + return (PAGER_ERROR); + +#ifdef CHECKSUM + /* + * Save checksum + */ + { + int checksum; + + checksum = compute_checksum(addr, size); + pager_put_checksum(ds, offset, checksum); + } +#endif /* CHECKSUM */ + offset = ptoa(block.block.p_offset); +ddprintf ("default_write(%x,%x,%x,%d)\n",addr,size,offset,block.block.p_index); + part = partition_of(block.block.p_index); + + /* + * There are various assumptions made here,we + * will not get into the next disk 'block' by + * accident. It might well be non-contiguous. + */ + do { + rc = page_write_file_direct(part->file, + offset, + addr, + size, + &wsize); + if (rc != 0) { + dprintf("*** PAGER ERROR: default_write: "); + dprintf("ds=0x%x addr=0x%x size=0x%x offset=0x%x resid=0x%x\n", + ds, addr, size, offset, wsize); + return (PAGER_ERROR); + } + addr += wsize; + offset += wsize; + size -= wsize; + } while (size != 0); + return (PAGER_SUCCESS); +} + +boolean_t +default_has_page(ds, offset) + dpager_t ds; + vm_offset_t offset; +{ + return ( ! no_block(pager_read_offset(ds, offset)) ); +} +/* + + */ + +/* + * Mapping between pager port and paging object. + */ +struct dstruct { + queue_chain_t links; /* Link in pager-port list */ + + struct mutex lock; /* Lock for the structure */ + struct condition + waiting_seqno, /* someone waiting on seqno */ + waiting_read, /* someone waiting on readers */ + waiting_write, /* someone waiting on writers */ + waiting_refs; /* someone waiting on refs */ + + memory_object_t pager; /* Pager port */ + mach_port_seqno_t seqno; /* Pager port sequence number */ + mach_port_t pager_request; /* Request port */ + mach_port_urefs_t request_refs; /* Request port user-refs */ + mach_port_t pager_name; /* Name port */ + mach_port_urefs_t name_refs; /* Name port user-refs */ + boolean_t external; /* Is an external object? */ + + unsigned int readers; /* Reads in progress */ + unsigned int writers; /* Writes in progress */ + + /* This is the reply port of an outstanding + default_pager_object_set_size call. */ + mach_port_t lock_request; + + unsigned int errors; /* Pageout error count */ + struct dpager dpager; /* Actual pager */ +}; +typedef struct dstruct * default_pager_t; +#define DEFAULT_PAGER_NULL ((default_pager_t)0) + +#if PARALLEL +#define dstruct_lock_init(ds) mutex_init(&ds->lock) +#define dstruct_lock(ds) mutex_lock(&ds->lock) +#define dstruct_unlock(ds) mutex_unlock(&ds->lock) +#else /* PARALLEL */ +#define dstruct_lock_init(ds) +#define dstruct_lock(ds) +#define dstruct_unlock(ds) +#endif /* PARALLEL */ + +/* + * List of all pagers. A specific pager is + * found directly via its port, this list is + * only used for monitoring purposes by the + * default_pager_object* calls + */ +struct pager_port { + queue_head_t queue; + struct mutex lock; + int count; /* saves code */ + queue_head_t leak_queue; +} all_pagers; + +#define pager_port_list_init() \ +{ \ + mutex_init(&all_pagers.lock); \ + queue_init(&all_pagers.queue); \ + queue_init(&all_pagers.leak_queue); \ + all_pagers.count = 0; \ +} + +void pager_port_list_insert(port, ds) + mach_port_t port; + default_pager_t ds; +{ + mutex_lock(&all_pagers.lock); + queue_enter(&all_pagers.queue, ds, default_pager_t, links); + all_pagers.count++; + mutex_unlock(&all_pagers.lock); +} + +/* given a data structure return a good port-name to associate it to */ +#define pnameof(_x_) (((vm_offset_t)(_x_))+1) +/* reverse, assumes no-odd-pointers */ +#define dnameof(_x_) (((vm_offset_t)(_x_))&~1) + +/* The magic typecast */ +#define pager_port_lookup(_port_) \ + ((! MACH_PORT_VALID(_port_) || \ + ((default_pager_t)dnameof(_port_))->pager != (_port_)) ? \ + DEFAULT_PAGER_NULL : (default_pager_t)dnameof(_port_)) + +void pager_port_list_delete(ds) + default_pager_t ds; +{ + mutex_lock(&all_pagers.lock); + queue_remove(&all_pagers.queue, ds, default_pager_t, links); + all_pagers.count--; + mutex_unlock(&all_pagers.lock); +} + +/* + * Destroy a paging partition. + * XXX this is not re-entrant XXX + */ +kern_return_t +destroy_paging_partition(name, pp_private) + char *name; + void **pp_private; +{ + register unsigned int id = part_id(name); + register partition_t part; + boolean_t all_ok = TRUE; + default_pager_t entry; + int pindex; + + /* + * Find and take partition out of list + * This prevents choose_partition from + * getting in the way. + */ + mutex_lock(&all_partitions.lock); + for (pindex = 0; pindex < all_partitions.n_partitions; pindex++) { + part = partition_of(pindex); + if (part && (part->id == id)) break; + } + if (pindex == all_partitions.n_partitions) { + mutex_unlock(&all_partitions.lock); + return KERN_INVALID_ARGUMENT; + } + part->going_away = TRUE; + mutex_unlock(&all_partitions.lock); + + /* + * This might take a while.. + */ +all_over_again: +#if debug +dprintf("Partition x%x (id x%x) for %s, all_ok %d\n", part, id, name, all_ok); +#endif + all_ok = TRUE; + mutex_lock(&part->p_lock); + + mutex_lock(&all_pagers.lock); + queue_iterate(&all_pagers.queue, entry, default_pager_t, links) { + + dstruct_lock(entry); + + if (!mutex_try_lock(&entry->dpager.lock)) { + + dstruct_unlock(entry); + mutex_unlock(&all_pagers.lock); + mutex_unlock(&part->p_lock); + + /* yield the processor */ + (void) thread_switch(MACH_PORT_NULL, + SWITCH_OPTION_NONE, 0); + + goto all_over_again; + + } + + /* + * See if we can relocate all the pages of this object + * currently on this partition on some other partition + */ + all_ok = pager_realloc(&entry->dpager, pindex); + + mutex_unlock(&entry->dpager.lock); + dstruct_unlock(entry); + + if (!all_ok) break; + + } + mutex_unlock(&all_pagers.lock); + + if (all_ok) { + /* No need to unlock partition, there are no refs left */ + + set_partition_of(pindex, 0); + *pp_private = part->file; + kfree(part->bitmap, howmany(part->total_size, NB_BM) * sizeof(bm_entry_t)); + kfree(part, sizeof(struct part)); + dprintf("%s Removed paging partition %s\n", my_name, name); + return KERN_SUCCESS; + } + + /* + * Put partition back in. + */ + part->going_away = FALSE; + + return KERN_FAILURE; +} + + +/* + * We use the sequence numbers on requests to regulate + * our parallelism. In general, we allow multiple reads and writes + * to proceed in parallel, with the exception that reads must + * wait for previous writes to finish. (Because the kernel might + * generate a data-request for a page on the heels of a data-write + * for the same page, and we must avoid returning stale data.) + * terminate requests wait for proceeding reads and writes to finish. + */ + +unsigned int default_pager_total = 0; /* debugging */ +unsigned int default_pager_wait_seqno = 0; /* debugging */ +unsigned int default_pager_wait_read = 0; /* debugging */ +unsigned int default_pager_wait_write = 0; /* debugging */ +unsigned int default_pager_wait_refs = 0; /* debugging */ + +#if PARALLEL +/* + * Waits for correct sequence number. Leaves pager locked. + */ +void pager_port_lock(ds, seqno) + default_pager_t ds; + mach_port_seqno_t seqno; +{ + default_pager_total++; +ddprintf ("pager_port_lock <%p>: <%p>: %d: 1\n", &ds, ds, seqno); + dstruct_lock(ds); +ddprintf ("pager_port_lock <%p>: <%p>: %d: 2\n", &ds, ds, seqno); + while (ds->seqno != seqno) { +ddprintf ("pager_port_lock <%p>: <%p>: %d: 3\n", &ds, ds, seqno); + default_pager_wait_seqno++; + condition_wait(&ds->waiting_seqno, &ds->lock); +ddprintf ("pager_port_lock <%p>: <%p>: %d: 4\n", &ds, ds, seqno); + } +} + +/* + * Increments sequence number and unlocks pager. + */ +void pager_port_unlock(ds) + default_pager_t ds; +{ + ds->seqno++; +ddprintf ("pager_port_unlock <%p>: <%p>: seqno => %d\n", &ds, ds, ds->seqno); + dstruct_unlock(ds); +ddprintf ("pager_port_unlock <%p>: <%p>: 2\n", &ds, ds); + condition_broadcast(&ds->waiting_seqno); +ddprintf ("pager_port_unlock <%p>: <%p>: 3\n", &ds, ds); +} + +/* + * Start a read - one more reader. Pager must be locked. + */ +void pager_port_start_read(ds) + default_pager_t ds; +{ + ds->readers++; +} + +/* + * Wait for readers. Unlocks and relocks pager if wait needed. + */ +void pager_port_wait_for_readers(ds) + default_pager_t ds; +{ + while (ds->readers != 0) { + default_pager_wait_read++; + condition_wait(&ds->waiting_read, &ds->lock); + } +} + +/* + * Finish a read. Pager is unlocked and returns unlocked. + */ +void pager_port_finish_read(ds) + default_pager_t ds; +{ + dstruct_lock(ds); + if (--ds->readers == 0) { + dstruct_unlock(ds); + condition_broadcast(&ds->waiting_read); + } + else { + dstruct_unlock(ds); + } +} + +/* + * Start a write - one more writer. Pager must be locked. + */ +void pager_port_start_write(ds) + default_pager_t ds; +{ + ds->writers++; +} + +/* + * Wait for writers. Unlocks and relocks pager if wait needed. + */ +void pager_port_wait_for_writers(ds) + default_pager_t ds; +{ + while (ds->writers != 0) { + default_pager_wait_write++; + condition_wait(&ds->waiting_write, &ds->lock); + } +} + +/* + * Finish a write. Pager is unlocked and returns unlocked. + */ +void pager_port_finish_write(ds) + default_pager_t ds; +{ + dstruct_lock(ds); + if (--ds->writers == 0) { + dstruct_unlock(ds); + condition_broadcast(&ds->waiting_write); + } + else { + dstruct_unlock(ds); + } +} + +/* + * Wait for concurrent default_pager_objects. + * Unlocks and relocks pager if wait needed. + */ +void pager_port_wait_for_refs(ds) + default_pager_t ds; +{ + while (ds->name_refs == 0) { + default_pager_wait_refs++; + condition_wait(&ds->waiting_refs, &ds->lock); + } +} + +/* + * Finished creating name refs - wake up waiters. + */ +void pager_port_finish_refs(ds) + default_pager_t ds; +{ + condition_broadcast(&ds->waiting_refs); +} + +#else /* PARALLEL */ + +#define pager_port_lock(ds,seqno) +#define pager_port_unlock(ds) +#define pager_port_start_read(ds) +#define pager_port_wait_for_readers(ds) +#define pager_port_finish_read(ds) +#define pager_port_start_write(ds) +#define pager_port_wait_for_writers(ds) +#define pager_port_finish_write(ds) +#define pager_port_wait_for_refs(ds) +#define pager_port_finish_refs(ds) + +#endif /* PARALLEL */ + +/* + * Default pager. + */ +task_t default_pager_self; /* Our task port. */ + +mach_port_t default_pager_default_port; /* Port for memory_object_create. */ + +/* We catch exceptions on ourself & startup using this port. */ +mach_port_t default_pager_exception_port; + +mach_port_t default_pager_internal_set; /* Port set for internal objects. */ +mach_port_t default_pager_external_set; /* Port set for external objects. */ +mach_port_t default_pager_default_set; /* Port set for "default" thread. */ + +typedef struct default_pager_thread { + cthread_t dpt_thread; /* Server thread. */ + vm_offset_t dpt_buffer; /* Read buffer. */ + boolean_t dpt_internal; /* Do we handle internal objects? */ +} default_pager_thread_t; + +#if PARALLEL + /* determine number of threads at run time */ +#define DEFAULT_PAGER_INTERNAL_COUNT (0) + +#else /* PARALLEL */ +#define DEFAULT_PAGER_INTERNAL_COUNT (1) +#endif /* PARALLEL */ + +/* Memory created by default_pager_object_create should mostly be resident. */ +#define DEFAULT_PAGER_EXTERNAL_COUNT (1) + +unsigned int default_pager_internal_count = DEFAULT_PAGER_INTERNAL_COUNT; + /* Number of "internal" threads. */ +unsigned int default_pager_external_count = DEFAULT_PAGER_EXTERNAL_COUNT; + /* Number of "external" threads. */ + +default_pager_t pager_port_alloc(size) + vm_size_t size; +{ + default_pager_t ds; + p_index_t part; + + ds = (default_pager_t) kalloc(sizeof *ds); + if (ds == DEFAULT_PAGER_NULL) + panic("%spager_port_alloc",my_name); + bzero((char *) ds, sizeof *ds); + + dstruct_lock_init(ds); + + /* + * Get a suitable partition. If none big enough + * just pick one and overcommit. If no partitions + * at all.. well just fake one so that we will + * kill specific objects on pageouts rather than + * panicing the system now. + */ + part = choose_partition(size, P_INDEX_INVALID); + if (no_partition(part)) { + overcommitted(FALSE, atop(size)); + part = choose_partition(0,P_INDEX_INVALID); +#if debug + if (no_partition(part)) + dprintf("%s No paging space at all !!\n", my_name); +#endif + } + pager_alloc(&ds->dpager, part, size); + + return ds; +} + +mach_port_urefs_t default_pager_max_urefs = 10000; + +/* + * Check user reference count on pager_request port. + * Pager must be locked. + * Unlocks and re-locks pager if needs to call kernel. + */ +void pager_port_check_request(ds, pager_request) + default_pager_t ds; + mach_port_t pager_request; +{ + mach_port_delta_t delta; + kern_return_t kr; + + assert(ds->pager_request == pager_request); + + if (++ds->request_refs > default_pager_max_urefs) { + delta = 1 - ds->request_refs; + ds->request_refs = 1; + + dstruct_unlock(ds); + + /* + * Deallocate excess user references. + */ + + kr = mach_port_mod_refs(default_pager_self, pager_request, + MACH_PORT_RIGHT_SEND, delta); + if (kr != KERN_SUCCESS) + panic("%spager_port_check_request",my_name); + + dstruct_lock(ds); + } +} + +void default_pager_add(ds, internal) + default_pager_t ds; + boolean_t internal; +{ + mach_port_t pager = ds->pager; + mach_port_t pset; + mach_port_mscount_t sync; + mach_port_t previous; + kern_return_t kr; + static char here[] = "%sdefault_pager_add"; + + /* + * The port currently has a make-send count of zero, + * because either we just created the port or we just + * received the port in a memory_object_create request. + */ + + if (internal) { + /* possibly generate an immediate no-senders notification */ + sync = 0; + pset = default_pager_internal_set; + ds->external = FALSE; + } else { + /* delay notification till send right is created */ + sync = 1; + pset = default_pager_external_set; + ds->external = TRUE; + } + + kr = mach_port_request_notification(default_pager_self, pager, + MACH_NOTIFY_NO_SENDERS, sync, + pager, MACH_MSG_TYPE_MAKE_SEND_ONCE, + &previous); + if ((kr != KERN_SUCCESS) || (previous != MACH_PORT_NULL)) + panic(here,my_name); + + kr = mach_port_move_member(default_pager_self, pager, pset); + if (kr != KERN_SUCCESS) + panic(here,my_name); +} + +/* + * Routine: memory_object_create + * Purpose: + * Handle requests for memory objects from the + * kernel. + * Notes: + * Because we only give out the default memory + * manager port to the kernel, we don't have to + * be so paranoid about the contents. + */ +kern_return_t +seqnos_memory_object_create(old_pager, seqno, new_pager, new_size, + new_pager_request, new_pager_name, new_page_size) + mach_port_t old_pager; + mach_port_seqno_t seqno; + mach_port_t new_pager; + vm_size_t new_size; + mach_port_t new_pager_request; + mach_port_t new_pager_name; + vm_size_t new_page_size; +{ + register default_pager_t ds; + kern_return_t kr; + + assert(old_pager == default_pager_default_port); + assert(MACH_PORT_VALID(new_pager_request)); + assert(MACH_PORT_VALID(new_pager_name)); + assert(new_page_size == vm_page_size); + + ds = pager_port_alloc(new_size); +rename_it: + kr = mach_port_rename( default_pager_self, + new_pager, (mach_port_t)pnameof(ds)); + if (kr != KERN_SUCCESS) { + default_pager_t ds1; + + if (kr != KERN_NAME_EXISTS) + panic("%s m_o_create", my_name); + ds1 = (default_pager_t) kalloc(sizeof *ds1); + *ds1 = *ds; + mutex_lock(&all_pagers.lock); + queue_enter(&all_pagers.leak_queue, ds, default_pager_t, links); + mutex_unlock(&all_pagers.lock); + ds = ds1; + goto rename_it; + } + + new_pager = (mach_port_t) pnameof(ds); + + /* + * Set up associations between these ports + * and this default_pager structure + */ + + ds->pager = new_pager; + ds->pager_request = new_pager_request; + ds->request_refs = 1; + ds->pager_name = new_pager_name; + ds->name_refs = 1; + + /* + * After this, other threads might receive requests + * for this memory object or find it in the port list. + */ + + pager_port_list_insert(new_pager, ds); + default_pager_add(ds, TRUE); + + return(KERN_SUCCESS); +} + +memory_object_copy_strategy_t default_pager_copy_strategy = + MEMORY_OBJECT_COPY_DELAY; + +kern_return_t +seqnos_memory_object_init(pager, seqno, pager_request, pager_name, + pager_page_size) + mach_port_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + mach_port_t pager_name; + vm_size_t pager_page_size; +{ + register default_pager_t ds; + kern_return_t kr; + static char here[] = "%sinit"; + + assert(MACH_PORT_VALID(pager_request)); + assert(MACH_PORT_VALID(pager_name)); + assert(pager_page_size == vm_page_size); + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + panic(here, my_name); + pager_port_lock(ds, seqno); + + if (ds->pager_request != MACH_PORT_NULL) + panic(here, my_name); + + ds->pager_request = pager_request; + ds->request_refs = 1; + ds->pager_name = pager_name; + ds->name_refs = 1; + + /* + * Even if the kernel immediately terminates the object, + * the pager_request port won't be destroyed until + * we process the terminate request, which won't happen + * until we unlock the object. + */ + + kr = memory_object_set_attributes(pager_request, + TRUE, + FALSE, /* do not cache */ + default_pager_copy_strategy); + if (kr != KERN_SUCCESS) + panic(here, my_name); + + pager_port_unlock(ds); + + return(KERN_SUCCESS); +} + +kern_return_t +seqnos_memory_object_terminate(pager, seqno, pager_request, pager_name) + mach_port_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + mach_port_t pager_name; +{ + register default_pager_t ds; + mach_port_urefs_t request_refs, name_refs; + kern_return_t kr; + static char here[] = "%sterminate"; + + /* + * pager_request and pager_name are receive rights, + * not send rights. + */ + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + panic(here, my_name); +ddprintf ("seqnos_memory_object_terminate <%p>: pager_port_lock: <%p>[s:%d,r:%d,w:%d,l:%d], %d\n", + &kr, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held, seqno); + pager_port_lock(ds, seqno); + + /* + * Wait for read and write requests to terminate. + */ + + pager_port_wait_for_readers(ds); + pager_port_wait_for_writers(ds); + + /* + * After memory_object_terminate both memory_object_init + * and a no-senders notification are possible, so we need + * to clean up the request and name ports but leave + * the pager port. + * + * A concurrent default_pager_objects might be allocating + * more references for the name port. In this case, + * we must first wait for it to finish. + */ + + pager_port_wait_for_refs(ds); + + ds->pager_request = MACH_PORT_NULL; + request_refs = ds->request_refs; + ds->request_refs = 0; + assert(ds->pager_name == pager_name); + ds->pager_name = MACH_PORT_NULL; + name_refs = ds->name_refs; + ds->name_refs = 0; +ddprintf ("seqnos_memory_object_terminate <%p>: pager_port_unlock: <%p>[s:%d,r:%d,w:%d,l:%d]\n", + &kr, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held); + pager_port_unlock(ds); + + /* + * Now we deallocate our various port rights. + */ + + kr = mach_port_mod_refs(default_pager_self, pager_request, + MACH_PORT_RIGHT_SEND, -request_refs); + if (kr != KERN_SUCCESS) + panic(here,my_name); + + kr = mach_port_mod_refs(default_pager_self, pager_request, + MACH_PORT_RIGHT_RECEIVE, -1); + if (kr != KERN_SUCCESS) + panic(here,my_name); + + kr = mach_port_mod_refs(default_pager_self, pager_name, + MACH_PORT_RIGHT_SEND, -name_refs); + if (kr != KERN_SUCCESS) + panic(here,my_name); + + kr = mach_port_mod_refs(default_pager_self, pager_name, + MACH_PORT_RIGHT_RECEIVE, -1); + if (kr != KERN_SUCCESS) + panic(here,my_name); + + return (KERN_SUCCESS); +} + +void default_pager_no_senders(pager, seqno, mscount) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_mscount_t mscount; +{ + register default_pager_t ds; + kern_return_t kr; + static char here[] = "%sno_senders"; + + /* + * Because we don't give out multiple send rights + * for a memory object, there can't be a race + * between getting a no-senders notification + * and creating a new send right for the object. + * Hence we don't keep track of mscount. + */ + + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + panic(here,my_name); + pager_port_lock(ds, seqno); + + /* + * We shouldn't get a no-senders notification + * when the kernel has the object cached. + */ + + if (ds->pager_request != MACH_PORT_NULL) + panic(here,my_name); + + /* + * Unlock the pager (though there should be no one + * waiting for it). + */ + dstruct_unlock(ds); + + /* + * Remove the memory object port association, and then + * the destroy the port itself. We must remove the object + * from the port list before deallocating the pager, + * because of default_pager_objects. + */ + + pager_port_list_delete(ds); + pager_dealloc(&ds->dpager); + + kr = mach_port_mod_refs(default_pager_self, pager, + MACH_PORT_RIGHT_RECEIVE, -1); + if (kr != KERN_SUCCESS) + panic(here,my_name); + + /* + * Do this *after* deallocating the port name + */ + kfree((char *) ds, sizeof(*ds)); + + /* + * Recover memory that we might have wasted because + * of name conflicts + */ + mutex_lock(&all_pagers.lock); + + while (!queue_empty(&all_pagers.leak_queue)) { + + ds = (default_pager_t) queue_first(&all_pagers.leak_queue); + queue_remove_first(&all_pagers.leak_queue, ds, default_pager_t, links); + kfree((char *) ds, sizeof(*ds)); + } + + mutex_unlock(&all_pagers.lock); +} + +int default_pager_pagein_count = 0; +int default_pager_pageout_count = 0; + +kern_return_t +seqnos_memory_object_data_request(pager, seqno, reply_to, offset, + length, protection_required) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t reply_to; + vm_offset_t offset; + vm_size_t length; + vm_prot_t protection_required; +{ + default_pager_thread_t *dpt; + default_pager_t ds; + vm_offset_t addr; + unsigned int errors; + kern_return_t rc; + static char here[] = "%sdata_request"; + + dpt = (default_pager_thread_t *) cthread_data(cthread_self()); + + if (length != vm_page_size) + panic(here,my_name); + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + panic(here,my_name); +ddprintf ("seqnos_memory_object_data_request <%p>: pager_port_lock: <%p>[s:%d,r:%d,w:%d,l:%d], %d\n", + &ds, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held, seqno); + pager_port_lock(ds, seqno); + pager_port_check_request(ds, reply_to); + pager_port_wait_for_writers(ds); + pager_port_start_read(ds); + + /* + * Get error count while pager locked. + */ + errors = ds->errors; + +ddprintf ("seqnos_memory_object_data_request <%p>: pager_port_unlock: <%p>[s:%d,r:%d,w:%d,l:%d]\n", + &ds, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held); + pager_port_unlock(ds); + + if (errors) { + dprintf("%s %s\n", my_name, + "dropping data_request because of previous paging errors"); + (void) memory_object_data_error(reply_to, + offset, vm_page_size, + KERN_FAILURE); + goto done; + } + + if (offset >= ds->dpager.limit) + rc = PAGER_ERROR; + else + rc = default_read(&ds->dpager, dpt->dpt_buffer, + vm_page_size, offset, + &addr, protection_required & VM_PROT_WRITE, + ds->external); + + switch (rc) { + case PAGER_SUCCESS: + if (addr != dpt->dpt_buffer) { + /* + * Deallocates data buffer + */ + (void) memory_object_data_supply( + reply_to, offset, + addr, vm_page_size, TRUE, + VM_PROT_NONE, + FALSE, MACH_PORT_NULL); + } else { + (void) memory_object_data_provided( + reply_to, offset, + addr, vm_page_size, + VM_PROT_NONE); + } + break; + + case PAGER_ABSENT: + (void) memory_object_data_unavailable( + reply_to, + offset, + vm_page_size); + break; + + case PAGER_ERROR: + (void) memory_object_data_error( + reply_to, + offset, + vm_page_size, + KERN_FAILURE); + break; + } + + default_pager_pagein_count++; + + done: + pager_port_finish_read(ds); + return(KERN_SUCCESS); +} + +/* + * memory_object_data_initialize: check whether we already have each page, and + * write it if we do not. The implementation is far from optimized, and + * also assumes that the default_pager is single-threaded. + */ +kern_return_t +seqnos_memory_object_data_initialize(pager, seqno, pager_request, + offset, addr, data_cnt) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + register + vm_offset_t offset; + register + pointer_t addr; + vm_size_t data_cnt; +{ + vm_offset_t amount_sent; + default_pager_t ds; + static char here[] = "%sdata_initialize"; + +#ifdef lint + pager_request++; +#endif /* lint */ + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + panic(here,my_name); +ddprintf ("seqnos_memory_object_data_initialize <%p>: pager_port_lock: <%p>[s:%d,r:%d,w:%d,l:%d], %d\n", + &ds, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held, seqno); + pager_port_lock(ds, seqno); + pager_port_check_request(ds, pager_request); + pager_port_start_write(ds); +ddprintf ("seqnos_memory_object_data_initialize <%p>: pager_port_unlock: <%p>[s:%d,r:%d,w:%d,l:%d]\n", + &ds, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held); + pager_port_unlock(ds); + + for (amount_sent = 0; + amount_sent < data_cnt; + amount_sent += vm_page_size) { + + if (!default_has_page(&ds->dpager, offset + amount_sent)) { + if (default_write(&ds->dpager, + addr + amount_sent, + vm_page_size, + offset + amount_sent) + != PAGER_SUCCESS) { + dprintf("%s%s write error\n", my_name, here); + dstruct_lock(ds); + ds->errors++; + dstruct_unlock(ds); + } + } + } + + pager_port_finish_write(ds); + if (vm_deallocate(default_pager_self, addr, data_cnt) != KERN_SUCCESS) + panic(here,my_name); + + return(KERN_SUCCESS); +} + +/* + * memory_object_data_write: split up the stuff coming in from + * a memory_object_data_write call + * into individual pages and pass them off to default_write. + */ +kern_return_t +seqnos_memory_object_data_write(pager, seqno, pager_request, + offset, addr, data_cnt) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + register + vm_offset_t offset; + register + pointer_t addr; + vm_size_t data_cnt; +{ + register + vm_size_t amount_sent; + default_pager_t ds; + static char here[] = "%sdata_write"; + int err; + +#ifdef lint + pager_request++; +#endif /* lint */ + +ddprintf ("seqnos_memory_object_data_write <%p>: 1\n", &err); + if ((data_cnt % vm_page_size) != 0) + { + ddprintf ("fail 1: %d %d\n", data_cnt, vm_page_size); + panic(here,my_name); + } + + +ddprintf ("seqnos_memory_object_data_write <%p>: 2\n", &err); + ds = pager_port_lookup(pager); +ddprintf ("seqnos_memory_object_data_write <%p>: 3\n", &err); + if (ds == DEFAULT_PAGER_NULL) + { + ddprintf ("fail 2: %d %d\n", pager, ds); + panic(here,my_name); + } + +ddprintf ("seqnos_memory_object_data_write <%p>: 4\n", &err); +ddprintf ("seqnos_memory_object_data_write <%p>: pager_port_lock: <%p>[s:%d,r:%d,w:%d,l:%d], %d\n", + &err, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held, seqno); + pager_port_lock(ds, seqno); +ddprintf ("seqnos_memory_object_data_write <%p>: 5\n", &err); + pager_port_check_request(ds, pager_request); +ddprintf ("seqnos_memory_object_data_write <%p>: 6\n", &err); + pager_port_start_write(ds); +ddprintf ("seqnos_memory_object_data_write <%p>: 7\n", &err); +ddprintf ("seqnos_memory_object_data_write <%p>: pager_port_unlock: <%p>[s:%d,r:%d,w:%d,l:%d]\n", + &err, ds, ds->seqno, ds->readers, ds->writers, ds->lock.held); + pager_port_unlock(ds); + +ddprintf ("seqnos_memory_object_data_write <%p>: 8\n", &err); + for (amount_sent = 0; + amount_sent < data_cnt; + amount_sent += vm_page_size) { + + register int result; + +ddprintf ("seqnos_memory_object_data_write <%p>: 9\n", &err); + result = default_write(&ds->dpager, + addr + amount_sent, + vm_page_size, + offset + amount_sent); +ddprintf ("seqnos_memory_object_data_write <%p>: 10\n", &err); + if (result != KERN_SUCCESS) { +ddprintf ("seqnos_memory_object_data_write <%p>: 11\n", &err); +#if debug + dprintf("%s WRITE ERROR on default_pageout:", my_name); + dprintf(" pager=%x, offset=0x%x, length=0x%x, result=%d\n", + pager, offset+amount_sent, vm_page_size, result); +#endif + dstruct_lock(ds); + ds->errors++; + dstruct_unlock(ds); + } + default_pager_pageout_count++; + } + +ddprintf ("seqnos_memory_object_data_write <%p>: 12\n", &err); + pager_port_finish_write(ds); +ddprintf ("seqnos_memory_object_data_write <%p>: 13\n", &err); + err = vm_deallocate(default_pager_self, addr, data_cnt); +ddprintf ("seqnos_memory_object_data_write <%p>: 14\n", &err); + if (err != KERN_SUCCESS) + { + ddprintf ("fail 3: %s %s %s %s\n", default_pager_self, addr, data_cnt, &err); + + panic(here,my_name); + } + + +ddprintf ("seqnos_memory_object_data_write <%p>: 15\n", &err); + return(KERN_SUCCESS); +} + +/*ARGSUSED*/ +kern_return_t +seqnos_memory_object_copy(old_memory_object, seqno, old_memory_control, + offset, length, new_memory_object) + memory_object_t old_memory_object; + mach_port_seqno_t seqno; + memory_object_control_t + old_memory_control; + vm_offset_t offset; + vm_size_t length; + memory_object_t new_memory_object; +{ + panic("%scopy", my_name); + return KERN_FAILURE; +} + +/* We get this when our memory_object_lock_request has completed + after we truncated an object. */ +kern_return_t +seqnos_memory_object_lock_completed (memory_object_t pager, + mach_port_seqno_t seqno, + mach_port_t pager_request, + vm_offset_t offset, + vm_size_t length) +{ + default_pager_t ds; + + ds = pager_port_lookup(pager); + assert(ds != DEFAULT_PAGER_NULL); + + pager_port_lock(ds, seqno); + pager_port_wait_for_readers(ds); + pager_port_wait_for_writers(ds); + + /* Now that any in-core pages have been flushed, we can apply + the limit to prevent any new page-ins. */ + assert (page_aligned (offset)); + ds->dpager.limit = offset; + + default_pager_object_set_size_reply (ds->lock_request, KERN_SUCCESS); + ds->lock_request = MACH_PORT_NULL; + + if (ds->dpager.size > ds->dpager.limit / vm_page_size) + /* Deallocate the old backing store pages and shrink the page map. */ + pager_truncate (&ds->dpager, ds->dpager.limit / vm_page_size); + + pager_port_unlock(ds, seqno); + + return KERN_SUCCESS; +} + +kern_return_t +seqnos_memory_object_data_unlock(pager, seqno, pager_request, + offset, addr, data_cnt) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + vm_offset_t offset; + pointer_t addr; + vm_size_t data_cnt; +{ + panic("%sdata_unlock",my_name); + return(KERN_FAILURE); +} + +kern_return_t +seqnos_memory_object_supply_completed(pager, seqno, pager_request, + offset, length, + result, error_offset) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + vm_offset_t offset; + vm_size_t length; + kern_return_t result; + vm_offset_t error_offset; +{ + panic("%ssupply_completed",my_name); + return(KERN_FAILURE); +} + +kern_return_t +seqnos_memory_object_data_return(pager, seqno, pager_request, + offset, addr, data_cnt, + dirty, kernel_copy) + memory_object_t pager; + mach_port_seqno_t seqno; + mach_port_t pager_request; + vm_offset_t offset; + pointer_t addr; + vm_size_t data_cnt; + boolean_t dirty; + boolean_t kernel_copy; +{ + panic("%sdata_return",my_name); + return(KERN_FAILURE); +} + +kern_return_t +seqnos_memory_object_change_completed(pager, seqno, may_cache, copy_strategy) + memory_object_t pager; + mach_port_seqno_t seqno; + boolean_t may_cache; + memory_object_copy_strategy_t copy_strategy; +{ + panic("%schange_completed",my_name); + return(KERN_FAILURE); +} + + +boolean_t default_pager_notify_server(in, out) + mach_msg_header_t *in, *out; +{ + register mach_no_senders_notification_t *n = + (mach_no_senders_notification_t *) in; + + /* + * The only send-once rights we create are for + * receiving no-more-senders notifications. + * Hence, if we receive a message directed to + * a send-once right, we can assume it is + * a genuine no-senders notification from the kernel. + */ + + if ((n->not_header.msgh_bits != + MACH_MSGH_BITS(0, MACH_MSG_TYPE_PORT_SEND_ONCE)) || + (n->not_header.msgh_id != MACH_NOTIFY_NO_SENDERS)) + return FALSE; + + assert(n->not_header.msgh_size == sizeof *n); + assert(n->not_header.msgh_remote_port == MACH_PORT_NULL); + + assert(n->not_type.msgt_name == MACH_MSG_TYPE_INTEGER_32); + assert(n->not_type.msgt_size == 32); + assert(n->not_type.msgt_number == 1); + assert(n->not_type.msgt_inline); + assert(! n->not_type.msgt_longform); + + default_pager_no_senders(n->not_header.msgh_local_port, + n->not_header.msgh_seqno, n->not_count); + + out->msgh_remote_port = MACH_PORT_NULL; + return TRUE; +} + +extern boolean_t seqnos_memory_object_server(); +extern boolean_t seqnos_memory_object_default_server(); +extern boolean_t default_pager_server(); +extern boolean_t exc_server(); +extern boolean_t bootstrap_server(); +extern void bootstrap_compat(); + +mach_msg_size_t default_pager_msg_size_object = 128; + +boolean_t +default_pager_demux_object(in, out) + mach_msg_header_t *in; + mach_msg_header_t *out; +{ + /* + * We receive memory_object_data_initialize messages in + * the memory_object_default interface. + */ + +int rval; +ddprintf ("DPAGER DEMUX OBJECT <%p>: %d\n", in, in->msgh_id); +rval = + (seqnos_memory_object_server(in, out) || + seqnos_memory_object_default_server(in, out) || + default_pager_notify_server(in, out) || + default_pager_server(in, out)); +ddprintf ("DPAGER DEMUX OBJECT DONE <%p>: %d\n", in, in->msgh_id); +return rval; +} + +mach_msg_size_t default_pager_msg_size_default = 8 * 1024; + +boolean_t +default_pager_demux_default(in, out) + mach_msg_header_t *in; + mach_msg_header_t *out; +{ + if (in->msgh_local_port == default_pager_default_port) { + /* + * We receive memory_object_create messages in + * the memory_object_default interface. + */ + +int rval; +ddprintf ("DPAGER DEMUX DEFAULT <%p>: %d\n", in, in->msgh_id); +rval = + (seqnos_memory_object_default_server(in, out) || + default_pager_server(in, out)); +ddprintf ("DPAGER DEMUX DEFAULT DONE <%p>: %d\n", in, in->msgh_id); +return rval; + } else if (in->msgh_local_port == default_pager_exception_port) { + /* + * We receive exception messages for + * ourself and the startup task. + */ + + return exc_server(in, out); + } else { + panic(my_name); + return FALSE; + } +} + +/* + * We use multiple threads, for two reasons. + * + * First, memory objects created by default_pager_object_create + * are "external", instead of "internal". This means the kernel + * sends data (memory_object_data_write) to the object pageable. + * To prevent deadlocks, the external and internal objects must + * be managed by different threads. + * + * Second, the default pager uses synchronous IO operations. + * Spreading requests across multiple threads should + * recover some of the performance loss from synchronous IO. + * + * We have 3+ threads. + * One receives memory_object_create and + * default_pager_object_create requests. + * One or more manage internal objects. + * One or more manage external objects. + */ + +void +default_pager_thread_privileges() +{ + /* + * Set thread privileges. + */ + cthread_wire(); /* attach kernel thread to cthread */ + wire_thread(); /* grab a kernel stack and memory allocation + privileges */ +} + +any_t +default_pager_default_thread (arg) + any_t arg; +{ + kern_return_t kr; + default_pager_thread_privileges (); + for (;;) { + kr = mach_msg_server(default_pager_demux_default, + default_pager_msg_size_default, + default_pager_default_set); + panic(my_name, kr); + } +} + + + +any_t +default_pager_thread(arg) + any_t arg; +{ + default_pager_thread_t *dpt = (default_pager_thread_t *) arg; + mach_port_t pset; + kern_return_t kr; + + cthread_set_data(cthread_self(), (any_t) dpt); + + + /* + * Threads handling external objects cannot have + * privileges. Otherwise a burst of data-requests for an + * external object could empty the free-page queue, + * because the fault code only reserves real pages for + * requests sent to internal objects. + */ + + if (dpt->dpt_internal) { + default_pager_thread_privileges(); + pset = default_pager_internal_set; + } else { + pset = default_pager_external_set; + } + + for (;;) { + kr = mach_msg_server(default_pager_demux_object, + default_pager_msg_size_object, + pset); + panic(my_name, kr); + } +} + +void +start_default_pager_thread(internal) + boolean_t internal; +{ + default_pager_thread_t *dpt; + kern_return_t kr; + + dpt = (default_pager_thread_t *) kalloc(sizeof *dpt); + if (dpt == 0) + panic(my_name); + + dpt->dpt_internal = internal; + + kr = vm_allocate(default_pager_self, &dpt->dpt_buffer, + vm_page_size, TRUE); + if (kr != KERN_SUCCESS) + panic(my_name); + wire_memory(dpt->dpt_buffer, vm_page_size, + VM_PROT_READ|VM_PROT_WRITE); + + dpt->dpt_thread = cthread_fork(default_pager_thread, (any_t) dpt); +} + +void +default_pager_initialize(host_port) + mach_port_t host_port; +{ + memory_object_t DMM; + kern_return_t kr; + + /* + * This task will become the default pager. + */ + default_pager_self = mach_task_self(); + + /* + * Initialize the "default pager" port. + */ + kr = mach_port_allocate(default_pager_self, MACH_PORT_RIGHT_RECEIVE, + &default_pager_default_port); + if (kr != KERN_SUCCESS) + panic(my_name); + + DMM = default_pager_default_port; + kr = vm_set_default_memory_manager(host_port, &DMM); + if ((kr != KERN_SUCCESS) || MACH_PORT_VALID(DMM)) + panic(my_name); + + /* + * Initialize the exception port. + */ + kr = mach_port_allocate(default_pager_self, MACH_PORT_RIGHT_RECEIVE, + &default_pager_exception_port); + if (kr != KERN_SUCCESS) + panic(my_name); + + /* + * Arrange for wiring privileges. + */ + wire_setup(host_port); + + /* + * Find out how many CPUs we have, to determine the number + * of threads to create. + */ + if (default_pager_internal_count == 0) { + host_basic_info_data_t h_info; + natural_t h_info_count; + + h_info_count = HOST_BASIC_INFO_COUNT; + (void) host_info(host_port, HOST_BASIC_INFO, + (host_info_t)&h_info, &h_info_count); + + /* + * Random computation to get more parallelism on + * multiprocessors. + */ + default_pager_internal_count = + (h_info.avail_cpus > 32 ? 32 : h_info.avail_cpus) / 4 + 3; + } +} + +/* + * Initialize and Run the default pager + */ +void +default_pager() +{ + kern_return_t kr; + int i; + + default_pager_thread_privileges(); + + /* + * Wire down code, data, stack + */ + wire_all_memory(); + + + /* + * Initialize the list of all pagers. + */ + pager_port_list_init(); + + kr = mach_port_allocate(default_pager_self, MACH_PORT_RIGHT_PORT_SET, + &default_pager_internal_set); + if (kr != KERN_SUCCESS) + panic(my_name); + + kr = mach_port_allocate(default_pager_self, MACH_PORT_RIGHT_PORT_SET, + &default_pager_external_set); + if (kr != KERN_SUCCESS) + panic(my_name); + + kr = mach_port_allocate(default_pager_self, MACH_PORT_RIGHT_PORT_SET, + &default_pager_default_set); + if (kr != KERN_SUCCESS) + panic(my_name); + + kr = mach_port_move_member(default_pager_self, + default_pager_default_port, + default_pager_default_set); + if (kr != KERN_SUCCESS) + panic(my_name); + + kr = mach_port_move_member(default_pager_self, + default_pager_exception_port, + default_pager_default_set); + if (kr != KERN_SUCCESS) + panic(my_name); + + /* + * Now we create the threads that will actually + * manage objects. + */ + + for (i = 0; i < default_pager_internal_count; i++) + start_default_pager_thread(TRUE); + + for (i = 0; i < default_pager_external_count; i++) + start_default_pager_thread(FALSE); + + default_pager_default_thread(0); /* Become the default_pager server */ +#if 0 + cthread_fork (default_pager_default_thread, 0); + /* cthread_exit (cthread_self ()); */ + thread_suspend (mach_thread_self ()); +#endif +} + +/* + * Create an external object. + */ +kern_return_t +S_default_pager_object_create (mach_port_t pager, + mach_port_t *mem_obj, + vm_size_t size) +{ + default_pager_t ds; + mach_port_t port; + kern_return_t result; + + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; + + ds = pager_port_alloc(size); +rename_it: + port = (mach_port_t) pnameof(ds); + result = mach_port_allocate_name(default_pager_self, + MACH_PORT_RIGHT_RECEIVE, port); + if (result != KERN_SUCCESS) { + default_pager_t ds1; + + if (result != KERN_NAME_EXISTS) return (result); + + ds1 = (default_pager_t) kalloc(sizeof *ds1); + *ds1 = *ds; + mutex_lock(&all_pagers.lock); + queue_enter(&all_pagers.leak_queue, ds, default_pager_t, links); + mutex_unlock(&all_pagers.lock); + ds = ds1; + goto rename_it; + } + + /* + * Set up associations between these ports + * and this default_pager structure + */ + + ds->pager = port; + pager_port_list_insert(port, ds); + default_pager_add(ds, FALSE); + + *mem_obj = port; + return (KERN_SUCCESS); +} + +kern_return_t +S_default_pager_info (mach_port_t pager, + default_pager_info_t *infop) +{ + vm_size_t total, free; + + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; + + mutex_lock(&all_partitions.lock); + paging_space_info(&total, &free); + mutex_unlock(&all_partitions.lock); + + infop->dpi_total_space = ptoa(total); + infop->dpi_free_space = ptoa(free); + infop->dpi_page_size = vm_page_size; + return KERN_SUCCESS; +} + +kern_return_t +S_default_pager_objects (mach_port_t pager, + default_pager_object_array_t *objectsp, + natural_t *ocountp, + mach_port_array_t *portsp, + natural_t *pcountp) +{ + vm_offset_t oaddr; /* memory for objects */ + vm_size_t osize; /* current size */ + default_pager_object_t *objects; + natural_t opotential; + + vm_offset_t paddr; /* memory for ports */ + vm_size_t psize; /* current size */ + mach_port_t *ports; + natural_t ppotential; + + unsigned int actual; + unsigned int num_pagers; + kern_return_t kr; + default_pager_t entry; + + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; + + /* start with the inline memory */ + + num_pagers = 0; + + objects = *objectsp; + opotential = *ocountp; + + ports = *portsp; + ppotential = *pcountp; + + mutex_lock(&all_pagers.lock); + /* + * We will send no more than this many + */ + actual = all_pagers.count; + mutex_unlock(&all_pagers.lock); + + if (opotential < actual) { + vm_offset_t newaddr; + vm_size_t newsize; + + newsize = 2 * round_page(actual * sizeof *objects); + + kr = vm_allocate(default_pager_self, &newaddr, newsize, TRUE); + if (kr != KERN_SUCCESS) + goto nomemory; + + oaddr = newaddr; + osize = newsize; + opotential = osize/sizeof *objects; + objects = (default_pager_object_t *) oaddr; + } + + if (ppotential < actual) { + vm_offset_t newaddr; + vm_size_t newsize; + + newsize = 2 * round_page(actual * sizeof *ports); + + kr = vm_allocate(default_pager_self, &newaddr, newsize, TRUE); + if (kr != KERN_SUCCESS) + goto nomemory; + + paddr = newaddr; + psize = newsize; + ppotential = psize/sizeof *ports; + ports = (mach_port_t *) paddr; + } + + /* + * Now scan the list. + */ + + mutex_lock(&all_pagers.lock); + + num_pagers = 0; + queue_iterate(&all_pagers.queue, entry, default_pager_t, links) { + + mach_port_t port; + vm_size_t size; + + if ((num_pagers >= opotential) || + (num_pagers >= ppotential)) { + /* + * This should be rare. In any case, + * we will only miss recent objects, + * because they are added at the end. + */ + break; + } + + /* + * Avoid interfering with normal operations + */ + if (!mutex_try_lock(&entry->dpager.lock)) + goto not_this_one; + size = pager_allocated(&entry->dpager); + mutex_unlock(&entry->dpager.lock); + + dstruct_lock(entry); + + port = entry->pager_name; + if (port == MACH_PORT_NULL) { + /* + * The object is waiting for no-senders + * or memory_object_init. + */ + dstruct_unlock(entry); + goto not_this_one; + } + + /* + * We need a reference for the reply message. + * While we are unlocked, the bucket queue + * can change and the object might be terminated. + * memory_object_terminate will wait for us, + * preventing deallocation of the entry. + */ + + if (--entry->name_refs == 0) { + dstruct_unlock(entry); + + /* keep the list locked, wont take long */ + + kr = mach_port_mod_refs(default_pager_self, + port, MACH_PORT_RIGHT_SEND, + default_pager_max_urefs); + if (kr != KERN_SUCCESS) + panic("%sdefault_pager_objects",my_name); + + dstruct_lock(entry); + + entry->name_refs += default_pager_max_urefs; + pager_port_finish_refs(entry); + } + dstruct_unlock(entry); + + /* the arrays are wired, so no deadlock worries */ + + objects[num_pagers].dpo_object = (vm_offset_t) entry; + objects[num_pagers].dpo_size = size; + ports [num_pagers++] = port; + continue; +not_this_one: + /* + * Do not return garbage + */ + objects[num_pagers].dpo_object = (vm_offset_t) 0; + objects[num_pagers].dpo_size = 0; + ports [num_pagers++] = MACH_PORT_NULL; + + } + + mutex_unlock(&all_pagers.lock); + + /* + * Deallocate and clear unused memory. + * (Returned memory will automagically become pageable.) + */ + + if (objects == *objectsp) { + /* + * Our returned information fit inline. + * Nothing to deallocate. + */ + + *ocountp = num_pagers; + } else if (actual == 0) { + (void) vm_deallocate(default_pager_self, oaddr, osize); + + /* return zero items inline */ + *ocountp = 0; + } else { + vm_offset_t used; + + used = round_page(actual * sizeof *objects); + + if (used != osize) + (void) vm_deallocate(default_pager_self, + oaddr + used, osize - used); + + *objectsp = objects; + *ocountp = num_pagers; + } + + if (ports == *portsp) { + /* + * Our returned information fit inline. + * Nothing to deallocate. + */ + + *pcountp = num_pagers; + } else if (actual == 0) { + (void) vm_deallocate(default_pager_self, paddr, psize); + + /* return zero items inline */ + *pcountp = 0; + } else { + vm_offset_t used; + + used = round_page(actual * sizeof *ports); + + if (used != psize) + (void) vm_deallocate(default_pager_self, + paddr + used, psize - used); + + *portsp = ports; + *pcountp = num_pagers; + } + + return KERN_SUCCESS; + + nomemory: + + { + register int i; + for (i = 0; i < num_pagers; i++) + (void) mach_port_deallocate(default_pager_self, ports[i]); + } + + if (objects != *objectsp) + (void) vm_deallocate(default_pager_self, oaddr, osize); + + if (ports != *portsp) + (void) vm_deallocate(default_pager_self, paddr, psize); + + return KERN_RESOURCE_SHORTAGE; +} + + +kern_return_t +S_default_pager_object_pages (mach_port_t pager, + mach_port_t object, + default_pager_page_array_t *pagesp, + natural_t *countp) +{ + vm_offset_t addr; /* memory for page offsets */ + vm_size_t size; /* current memory size */ + default_pager_page_t *pages; + natural_t potential, actual; + kern_return_t kr; + + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; + + /* we start with the inline space */ + + pages = *pagesp; + potential = *countp; + + for (;;) { + default_pager_t entry; + + mutex_lock(&all_pagers.lock); + queue_iterate(&all_pagers.queue, entry, default_pager_t, links) { + dstruct_lock(entry); + if (entry->pager_name == object) { + mutex_unlock(&all_pagers.lock); + goto found_object; + } + dstruct_unlock(entry); + } + mutex_unlock(&all_pagers.lock); + + /* did not find the object */ + + if (pages != *pagesp) + (void) vm_deallocate(default_pager_self, addr, size); + return KERN_INVALID_ARGUMENT; + + found_object: + + if (!mutex_try_lock(&entry->dpager.lock)) { + /* oh well bad luck */ + + dstruct_unlock(entry); + + /* yield the processor */ + (void) thread_switch(MACH_PORT_NULL, + SWITCH_OPTION_NONE, 0); + continue; + } + + actual = pager_pages(&entry->dpager, pages, potential); + mutex_unlock(&entry->dpager.lock); + dstruct_unlock(entry); + + if (actual <= potential) + break; + + /* allocate more memory */ + + if (pages != *pagesp) + (void) vm_deallocate(default_pager_self, addr, size); + size = round_page(actual * sizeof *pages); + kr = vm_allocate(default_pager_self, &addr, size, TRUE); + if (kr != KERN_SUCCESS) + return kr; + pages = (default_pager_page_t *) addr; + potential = size/sizeof *pages; + } + + /* + * Deallocate and clear unused memory. + * (Returned memory will automagically become pageable.) + */ + + if (pages == *pagesp) { + /* + * Our returned information fit inline. + * Nothing to deallocate. + */ + + *countp = actual; + } else if (actual == 0) { + (void) vm_deallocate(default_pager_self, addr, size); + + /* return zero items inline */ + *countp = 0; + } else { + vm_offset_t used; + + used = round_page(actual * sizeof *pages); + + if (used != size) + (void) vm_deallocate(default_pager_self, + addr + used, size - used); + + *pagesp = pages; + *countp = actual; + } + return KERN_SUCCESS; +} + + +kern_return_t +S_default_pager_object_set_size (mach_port_t pager, + mach_port_t reply_to, + mach_port_seqno_t seqno, + vm_size_t limit) +{ + kern_return_t kr; + default_pager_t ds; + + ds = pager_port_lookup(pager); + if (ds == DEFAULT_PAGER_NULL) + return KERN_INVALID_ARGUMENT; + + pager_port_lock(ds, seqno); + pager_port_check_request(ds, reply_to); + pager_port_wait_for_readers(ds); + pager_port_wait_for_writers(ds); + + limit = round_page (limit); + if (ds->dpager.size <= limit / vm_page_size) + { + /* The limit has not been exceeded heretofore. Just change it. */ + ds->dpager.limit = limit; + kr = KERN_SUCCESS; + } + else if (ds->lock_request == MACH_PORT_NULL) + { + /* Tell the kernel to flush from core all the pages being removed. + We will get the memory_object_lock_completed callback when they + have been flushed. We handle that by completing the limit update + and posting the reply to the pending truncation. */ + kr = memory_object_lock_request (ds->pager_request, + limit, + ds->dpager.size * vm_page_size - limit, + MEMORY_OBJECT_RETURN_NONE, TRUE, + VM_PROT_ALL, ds->pager); + if (kr != KERN_SUCCESS) + panic ("memory_object_lock_request: %d", kr); + ds->lock_request = reply_to; + kr = MIG_NO_REPLY; + } + else + /* There is already another call in progress. Tough titties. */ + kr = KERN_FAILURE; + + pager_port_unlock(ds, seqno); + + return kr; +} + +/* + * Add/remove extra paging space + */ + +extern mach_port_t bootstrap_master_device_port; +extern mach_port_t bootstrap_master_host_port; + +kern_return_t +S_default_pager_paging_file (pager, mdport, file_name, add) + mach_port_t pager; + mach_port_t mdport; + default_pager_filename_t file_name; + boolean_t add; +{ + kern_return_t kr; + + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; + +#if 0 +dprintf("bmd %x md %x\n", bootstrap_master_device_port, mdport); +#endif + if (add) { + kr = add_paging_file(bootstrap_master_device_port, + file_name, 0); + } else { + kr = remove_paging_file(file_name); + } + + /* XXXX more code needed */ + if (mdport != bootstrap_master_device_port) + mach_port_deallocate( mach_task_self(), mdport); + + return kr; +} + +default_pager_register_fileserver(pager, fileserver) + mach_port_t pager; + mach_port_t fileserver; +{ + if (pager != default_pager_default_port) + return KERN_INVALID_ARGUMENT; +#if notyet + mach_port_deallocate(mach_task_self(), fileserver); + if (0) dp_helper_paging_space(0,0,0);/*just linkit*/ +#endif + return KERN_SUCCESS; +} + +/* + * When things do not quite workout... + */ +no_paging_space(out_of_memory) + boolean_t out_of_memory; +{ + static char here[] = "%s *** NOT ENOUGH PAGING SPACE ***"; + + if (out_of_memory) + dprintf("*** OUT OF MEMORY *** "); + panic(here, my_name); +} + +overcommitted(got_more_space, space) + boolean_t got_more_space; + vm_size_t space; /* in pages */ +{ + vm_size_t pages_free, pages_total; + + static boolean_t user_warned = FALSE; + static vm_size_t pages_shortage = 0; + + paging_space_info(&pages_total, &pages_free); + + /* + * If user added more space, see if it is enough + */ + if (got_more_space) { + pages_free -= pages_shortage; + if (pages_free > 0) { + pages_shortage = 0; + if (user_warned) + dprintf("%s paging space ok now.\n", my_name); + } else + pages_shortage = pages_free; + user_warned = FALSE; + return; + } + /* + * We ran out of gas, let user know. + */ + pages_free -= space; + pages_shortage = (pages_free > 0) ? 0 : -pages_free; + if (!user_warned && pages_shortage) { + user_warned = TRUE; + dprintf("%s paging space over-committed.\n", my_name); + } +#if debug + user_warned = FALSE; + dprintf("%s paging space over-committed [+%d (%d) pages].\n", + my_name, space, pages_shortage); +#endif +} + +paging_space_info(totp, freep) + vm_size_t *totp, *freep; +{ + register vm_size_t total, free; + register partition_t part; + register int i; + + total = free = 0; + for (i = 0; i < all_partitions.n_partitions; i++) { + + if ((part = partition_of(i)) == 0) continue; + + /* no need to lock: by the time this data + gets back to any remote requestor it + will be obsolete anyways */ + total += part->total_size; + free += part->free; +#if debug + dprintf("Partition %d: x%x total, x%x free\n", + i, part->total_size, part->free); +#endif + } + *totp = total; + *freep = free; +} + +/* + * Catch exceptions. + */ + +kern_return_t +catch_exception_raise(exception_port, thread, task, exception, code, subcode) + mach_port_t exception_port; + mach_port_t thread, task; + int exception, code, subcode; +{ + ddprintf ("(default_pager)catch_exception_raise(%d,%d,%d)\n", + exception, code, subcode); + panic(my_name); + + /* mach_msg_server will deallocate thread/task for us */ + + return KERN_FAILURE; +} |