diff options
Diffstat (limited to 'libpager')
| -rw-r--r-- | libpager/data-request.c | 3 | ||||
| -rw-r--r-- | libpager/data-return.c | 79 | ||||
| -rw-r--r-- | libpager/pager-create.c | 4 | ||||
| -rw-r--r-- | libpager/pager.h | 23 | ||||
| -rw-r--r-- | libpager/priv.h | 1 |
5 files changed, 88 insertions, 22 deletions
diff --git a/libpager/data-request.c b/libpager/data-request.c index 4454facb..34b8b438 100644 --- a/libpager/data-request.c +++ b/libpager/data-request.c @@ -119,7 +119,8 @@ _pager_seqnos_memory_object_data_request (mach_port_t object, goto error_read; memory_object_data_supply (p->memobjcntl, offset, page, length, 1, - write_lock ? VM_PROT_WRITE : VM_PROT_NONE, 0, + write_lock ? VM_PROT_WRITE : VM_PROT_NONE, + p->notify_on_evict ? 1 : 0, MACH_PORT_NULL); pthread_mutex_lock (&p->interlock); _pager_mark_object_error (p, offset, length, 0); diff --git a/libpager/data-return.c b/libpager/data-return.c index c70f0e8d..6a3b9037 100644 --- a/libpager/data-return.c +++ b/libpager/data-return.c @@ -39,6 +39,7 @@ _pager_do_write_request (mach_port_t object, struct pager *p; short *pm_entries; int npages, i; + char *notified; error_t *pagerrs; struct lock_request *lr; struct lock_list {struct lock_request *lr; @@ -71,9 +72,6 @@ _pager_do_write_request (mach_port_t object, goto release_out; } - if (! dirty) - goto release_out; - if (p->pager_state != NORMAL) { printf ("pager in wrong state for write\n"); @@ -83,6 +81,11 @@ _pager_do_write_request (mach_port_t object, npages = length / __vm_page_size; pagerrs = alloca (npages * sizeof (error_t)); + notified = alloca (npages * (sizeof *notified)); +#ifndef NDEBUG + memset (notified, -1, npages * (sizeof *notified)); +#endif + _pager_block_termination (p); /* until we are done with the pagemap when the write completes. */ @@ -90,6 +93,24 @@ _pager_do_write_request (mach_port_t object, pm_entries = &p->pagemap[offset / __vm_page_size]; + if (! dirty) + { + munmap ((void *) data, length); + if (!kcopy) { + /* Prepare notified array. */ + for (i = 0; i < npages; i++) + notified[i] = (p->notify_on_evict + && ! (pm_entries[i] & PM_PAGEINWAIT)); + + _pager_release_seqno (p, seqno); + goto notify; + } + else { + _pager_allow_termination (p); + goto release_out; + } + } + /* Make sure there are no other in-progress writes for any of these pages before we begin. This imposes a little more serialization than we really have to require (because *all* future writes on @@ -120,10 +141,6 @@ _pager_do_write_request (mach_port_t object, for (i = 0; i < npages; i++) pm_entries[i] |= PM_PAGINGOUT | PM_INIT; - if (!kcopy) - for (i = 0; i < npages; i++) - pm_entries[i] &= ~PM_INCORE; - /* If this write occurs while a lock is pending, record it. We have to keep this list because a lock request might come in while we do the I/O; in that case there @@ -163,7 +180,10 @@ _pager_do_write_request (mach_port_t object, for (i = 0; i < npages; i++) { if (omitdata & (1 << i)) - continue; + { + notified[i] = 0; + continue; + } if (pm_entries[i] & PM_WRITEWAIT) wakeup = 1; @@ -179,14 +199,22 @@ _pager_do_write_request (mach_port_t object, pm_entries[i] |= PM_INVALID; if (pm_entries[i] & PM_PAGEINWAIT) - memory_object_data_supply (p->memobjcntl, - offset + (vm_page_size * i), - data + (vm_page_size * i), - vm_page_size, 1, - VM_PROT_NONE, 0, MACH_PORT_NULL); + { + memory_object_data_supply (p->memobjcntl, + offset + (vm_page_size * i), + data + (vm_page_size * i), + vm_page_size, 1, + VM_PROT_NONE, 0, MACH_PORT_NULL); + notified[i] = 0; + } else - munmap ((caddr_t) (data + (vm_page_size * i)), - vm_page_size); + { + munmap ((void *) (data + (vm_page_size * i)), + vm_page_size); + notified[i] = (! kcopy && p->notify_on_evict); + if (! kcopy) + pm_entries[i] &= ~PM_INCORE; + } pm_entries[i] &= ~(PM_PAGINGOUT | PM_PAGEINWAIT | PM_WRITEWAIT); } @@ -198,10 +226,29 @@ _pager_do_write_request (mach_port_t object, if (wakeup) pthread_cond_broadcast (&p->wakeup); + notify: _pager_allow_termination (p); - pthread_mutex_unlock (&p->interlock); + for (i = 0; i < npages; i++) + { + assert (notified[i] == 0 || notified[i] == 1); + if (notified[i]) + { + short *pm_entry = &pm_entries[i]; + + /* Do notify user. */ + pager_notify_evict (p->upi, offset + (i * vm_page_size)); + + /* Clear any error that is left. Notification on eviction + is used only to change association of page, so any + error may no longer be valid. */ + pthread_mutex_lock (&p->interlock); + *pm_entry = SET_PM_ERROR (SET_PM_NEXTERROR (*pm_entry, 0), 0); + pthread_mutex_unlock (&p->interlock); + } + } + ports_port_deref (p); return 0; diff --git a/libpager/pager-create.c b/libpager/pager-create.c index 318c9f15..1aea6e96 100644 --- a/libpager/pager-create.c +++ b/libpager/pager-create.c @@ -22,7 +22,8 @@ struct pager * pager_create (struct user_pager_info *upi, struct port_bucket *bucket, boolean_t may_cache, - memory_object_copy_strategy_t copy_strategy) + memory_object_copy_strategy_t copy_strategy, + boolean_t notify_on_evict) { struct pager *p; @@ -38,6 +39,7 @@ pager_create (struct user_pager_info *upi, p->attribute_requests = 0; p->may_cache = may_cache; p->copy_strategy = copy_strategy; + p->notify_on_evict = notify_on_evict; p->memobjcntl = MACH_PORT_NULL; p->memobjname = MACH_PORT_NULL; p->seqno = -1; diff --git a/libpager/pager.h b/libpager/pager.h index 99fb3845..75ff108a 100644 --- a/libpager/pager.h +++ b/libpager/pager.h @@ -36,14 +36,17 @@ int pager_demuxer (mach_msg_header_t *inp, to receive requests. U_PAGER will be provided to later calls to pager_find_address. The pager will have one user reference created. MAY_CACHE and COPY_STRATEGY are the original values of - those attributes as for memory_object_ready. Users may create - references to pagers by use of the relevant ports library - functions. On errors, return null and set errno. */ + those attributes as for memory_object_ready. If NOTIFY_ON_EVICT is + non-zero, pager_notify_evict user callback will be called when page + is evicted. Users may create references to pagers by use of the + relevant ports library functions. On errors, return null and set + errno. */ struct pager * pager_create (struct user_pager_info *u_pager, struct port_bucket *bucket, boolean_t may_cache, - memory_object_copy_strategy_t copy_strategy); + memory_object_copy_strategy_t copy_strategy, + boolean_t notify_on_evict); /* Return the user_pager_info struct associated with a pager. */ struct user_pager_info * @@ -172,6 +175,18 @@ error_t pager_unlock_page (struct user_pager_info *pager, vm_offset_t address); +/* The user must define this function. It is used when you want be + able to change association of pages to backing store. To use it, + pass non-zero value in NOTIFY_ON_EVICT when pager is created with + pager_create. You can change association of page only when + pager_notify_evict has been called and you haven't touched page + content after that. Note there is a possibility that a page is + evicted, but user is not notified about that. The user should be + able to handle this case. */ +void +pager_notify_evict (struct user_pager_info *pager, + vm_offset_t page); + /* The user must define this function. It should report back (in *OFFSET and *SIZE the minimum valid address the pager will accept and the size of the object. */ diff --git a/libpager/priv.h b/libpager/priv.h index e6b2546b..7aa0fb44 100644 --- a/libpager/priv.h +++ b/libpager/priv.h @@ -49,6 +49,7 @@ struct pager boolean_t may_cache; memory_object_copy_strategy_t copy_strategy; + boolean_t notify_on_evict; /* Interface ports */ memory_object_control_t memobjcntl; |