xnu-4903.270.47.tar.gz

[apple/xnu.git] / bsd / dev / dtrace / dtrace_ptss.c

diff --git a/bsd/dev/dtrace/dtrace_ptss.c b/bsd/dev/dtrace/dtrace_ptss.c
index 6741f5563410f1d3cc7203e94d5aea1fc23343fe..b2cc59819e815869c59ab73a79d8d07255c6a697 100644 (file)
--- a/bsd/dev/dtrace/dtrace_ptss.c
+++ b/bsd/dev/dtrace/dtrace_ptss.c
@@ -2,7 +2,7 @@
  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

- * 
+ *

  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in


@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.

- * 
+ *

  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.

- * 
+ *

  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,


@@ -22,7 +22,7 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.

- * 
+ *

  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 


@@ -48,7 +48,8 @@
  * page of memory, the underlying kernel _MALLOC may block.
  */
 struct dtrace_ptss_page_entry*
  * page of memory, the underlying kernel _MALLOC may block.
  */
 struct dtrace_ptss_page_entry*

-dtrace_ptss_claim_entry_locked(struct proc* p) {
+dtrace_ptss_claim_entry_locked(struct proc* p)
+{

        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
 
        struct dtrace_ptss_page_entry* entry = NULL;
        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
 
        struct dtrace_ptss_page_entry* entry = NULL;


@@ -61,8 +62,9 @@ dtrace_ptss_claim_entry_locked(struct proc* p) {
                        struct dtrace_ptss_page* page = dtrace_ptss_allocate_page(p);
 
                        // Make sure we actually got a page
                        struct dtrace_ptss_page* page = dtrace_ptss_allocate_page(p);
 
                        // Make sure we actually got a page

-                       if (page == NULL)
+                       if (page == NULL) {

                                return NULL;
                                return NULL;

+                       }

 
                        // Add the page to the page list
                        page->next = p->p_dtrace_ptss_pages;
 
                        // Add the page to the page list
                        page->next = p->p_dtrace_ptss_pages;


@@ -70,18 +72,19 @@ dtrace_ptss_claim_entry_locked(struct proc* p) {
 
                        // CAS the entries onto the free list.
                        do {
 
                        // CAS the entries onto the free list.
                        do {

-                               page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next = p->p_dtrace_ptss_free_list;
-                       } while (!OSCompareAndSwapPtr((void *)page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next,
-                                                  (void *)&page->entries[0],
-                                                  (void * volatile *)&p->p_dtrace_ptss_free_list));
-                                
+                               page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next = p->p_dtrace_ptss_free_list;
+                       } while (!OSCompareAndSwapPtr((void *)page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next,
+                           (void *)&page->entries[0],
+                           (void * volatile *)&p->p_dtrace_ptss_free_list));
+

                        // Now that we've added to the free list, try again.
                        continue;
                }
 
                // Claim temp
                        // Now that we've added to the free list, try again.
                        continue;
                }
 
                // Claim temp

-               if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list))
+               if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list)) {

                        continue;
                        continue;

+               }

 
                // At this point, we own temp.
                entry = temp;
 
                // At this point, we own temp.
                entry = temp;


@@ -96,7 +99,8 @@ dtrace_ptss_claim_entry_locked(struct proc* p) {
  * This function does not require any locks to be held on entry.
  */
 struct dtrace_ptss_page_entry*
  * This function does not require any locks to be held on entry.
  */
 struct dtrace_ptss_page_entry*

-dtrace_ptss_claim_entry(struct proc* p) {
+dtrace_ptss_claim_entry(struct proc* p)
+{

        // Verify no locks held on entry
        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED);
        LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
        // Verify no locks held on entry
        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED);
        LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);


@@ -114,8 +118,9 @@ dtrace_ptss_claim_entry(struct proc* p) {
                }
 
                // Claim temp
                }
 
                // Claim temp

-               if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list))
+               if (!OSCompareAndSwapPtr((void *)temp, (void *)temp->next, (void * volatile *)&p->p_dtrace_ptss_free_list)) {

                        continue;
                        continue;

+               }

 
                // At this point, we own temp.
                entry = temp;
 
                // At this point, we own temp.
                entry = temp;


@@ -134,7 +139,8 @@ dtrace_ptss_claim_entry(struct proc* p) {
  * of releasing an entry to the free list is ignored.
  */
 void
  * of releasing an entry to the free list is ignored.
  */
 void

-dtrace_ptss_release_entry(struct proc* p, struct dtrace_ptss_page_entry* e) {
+dtrace_ptss_release_entry(struct proc* p, struct dtrace_ptss_page_entry* e)
+{

        if (p && p->p_dtrace_ptss_pages && e) {
                do {
                        e->next = p->p_dtrace_ptss_free_list;
        if (p && p->p_dtrace_ptss_pages && e) {
                do {
                        e->next = p->p_dtrace_ptss_free_list;


@@ -144,7 +150,7 @@ dtrace_ptss_release_entry(struct proc* p, struct dtrace_ptss_page_entry* e) {
 
 /*
  * This function allocates a new page in the target process's address space.
 
 /*
  * This function allocates a new page in the target process's address space.

- * 
+ *

  * It returns a dtrace_ptss_page that has its entries chained, with the last
  * entries next field set to NULL. It does not add the page or the entries to
  * the process's page/entry lists.
  * It returns a dtrace_ptss_page that has its entries chained, with the last
  * entries next field set to NULL. It does not add the page or the entries to
  * the process's page/entry lists.


@@ -156,24 +162,26 @@ dtrace_ptss_allocate_page(struct proc* p)
 {
        // Allocate the kernel side data
        struct dtrace_ptss_page* ptss_page = _MALLOC(sizeof(struct dtrace_ptss_page), M_TEMP, M_ZERO | M_WAITOK);
 {
        // Allocate the kernel side data
        struct dtrace_ptss_page* ptss_page = _MALLOC(sizeof(struct dtrace_ptss_page), M_TEMP, M_ZERO | M_WAITOK);

-       if (ptss_page == NULL)
+       if (ptss_page == NULL) {

                return NULL;
                return NULL;

+       }

 
        // Now allocate a page in user space and set its protections to allow execute.
        task_t task = p->task;
        vm_map_t map = get_task_map_reference(task);
 
        // Now allocate a page in user space and set its protections to allow execute.
        task_t task = p->task;
        vm_map_t map = get_task_map_reference(task);

-       if (map == NULL)
-         goto err;
+       if (map == NULL) {
+               goto err;
+       }

 
        mach_vm_size_t size = PAGE_MAX_SIZE;
        mach_vm_offset_t addr = 0;
        mach_vm_offset_t write_addr = 0;
 
        mach_vm_size_t size = PAGE_MAX_SIZE;
        mach_vm_offset_t addr = 0;
        mach_vm_offset_t write_addr = 0;

-       /* 
+       /*

         * The embedded OS has extra permissions for writable and executable pages.
         * To ensure correct permissions, we must set the page protections separately.
         */
         * The embedded OS has extra permissions for writable and executable pages.
         * To ensure correct permissions, we must set the page protections separately.
         */

-       vm_prot_t cur_protection = VM_PROT_READ|VM_PROT_EXECUTE;
-       vm_prot_t max_protection = VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE;
+       vm_prot_t cur_protection = VM_PROT_READ | VM_PROT_EXECUTE;
+       vm_prot_t max_protection = VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE;

 
        kern_return_t kr = mach_vm_map_kernel(map, &addr, size, 0, VM_FLAGS_ANYWHERE, VM_MAP_KERNEL_FLAGS_NONE, VM_KERN_MEMORY_NONE, IPC_PORT_NULL, 0, FALSE, cur_protection, max_protection, VM_INHERIT_DEFAULT);
        if (kr != KERN_SUCCESS) {
 
        kern_return_t kr = mach_vm_map_kernel(map, &addr, size, 0, VM_FLAGS_ANYWHERE, VM_MAP_KERNEL_FLAGS_NONE, VM_KERN_MEMORY_NONE, IPC_PORT_NULL, 0, FALSE, cur_protection, max_protection, VM_INHERIT_DEFAULT);
        if (kr != KERN_SUCCESS) {


@@ -183,24 +191,26 @@ dtrace_ptss_allocate_page(struct proc* p)
         * If on embedded, remap the scratch space as writable at another
         * virtual address
         */
         * If on embedded, remap the scratch space as writable at another
         * virtual address
         */

-        kr = mach_vm_remap_kernel(map, &write_addr, size, 0, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE, map, addr, FALSE, &cur_protection, &max_protection, VM_INHERIT_DEFAULT);
-       if (kr != KERN_SUCCESS || !(max_protection & VM_PROT_WRITE))
+       kr = mach_vm_remap_kernel(map, &write_addr, size, 0, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE, map, addr, FALSE, &cur_protection, &max_protection, VM_INHERIT_DEFAULT);
+       if (kr != KERN_SUCCESS || !(max_protection & VM_PROT_WRITE)) {

                goto err;
                goto err;

+       }

 
 

-       kr = mach_vm_protect (map, (mach_vm_offset_t)write_addr, (mach_vm_size_t)size, 0, VM_PROT_READ | VM_PROT_WRITE);
-       if (kr != KERN_SUCCESS)
+       kr = mach_vm_protect(map, (mach_vm_offset_t)write_addr, (mach_vm_size_t)size, 0, VM_PROT_READ | VM_PROT_WRITE);
+       if (kr != KERN_SUCCESS) {

                goto err;
                goto err;

+       }

 
        // Chain the page entries.
        int i;
 
        // Chain the page entries.
        int i;

-       for (i=0; i<DTRACE_PTSS_ENTRIES_PER_PAGE; i++) {
+       for (i = 0; i < DTRACE_PTSS_ENTRIES_PER_PAGE; i++) {

                ptss_page->entries[i].addr = addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);
                ptss_page->entries[i].write_addr = write_addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);
                ptss_page->entries[i].addr = addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);
                ptss_page->entries[i].write_addr = write_addr + (i * DTRACE_PTSS_SCRATCH_SPACE_PER_THREAD);

-               ptss_page->entries[i].next = &ptss_page->entries[i+1];
+               ptss_page->entries[i].next = &ptss_page->entries[i + 1];

        }
 
        // The last entry should point to NULL
        }
 
        // The last entry should point to NULL

-       ptss_page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE-1].next = NULL;
+       ptss_page->entries[DTRACE_PTSS_ENTRIES_PER_PAGE - 1].next = NULL;

 
        vm_map_deallocate(map);
 
 
        vm_map_deallocate(map);
 


@@ -209,15 +219,16 @@ dtrace_ptss_allocate_page(struct proc* p)
 err:
        _FREE(ptss_page, M_TEMP);
 
 err:
        _FREE(ptss_page, M_TEMP);
 

-       if (map)
-         vm_map_deallocate(map);
+       if (map) {
+               vm_map_deallocate(map);
+       }

 
        return NULL;
 }
 
 /*
  * This function frees an existing page in the target process's address space.
 
        return NULL;
 }
 
 /*
  * This function frees an existing page in the target process's address space.

- * 
+ *

  * It does not alter any of the process's page/entry lists.
  *
  * TODO: Inline in dtrace_ptrace_exec_exit?
  * It does not alter any of the process's page/entry lists.
  *
  * TODO: Inline in dtrace_ptrace_exec_exit?


@@ -243,10 +254,11 @@ dtrace_ptss_free_page(struct proc* p, struct dtrace_ptss_page* ptss_page)
 
 /*
  * This function assumes that the target process has been
 
 /*
  * This function assumes that the target process has been

- * suspended, and the proc_lock & sprlock is held 
+ * suspended, and the proc_lock & sprlock is held

  */
 void
  */
 void

-dtrace_ptss_enable(struct proc* p) {
+dtrace_ptss_enable(struct proc* p)
+{

        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
        LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_OWNED);
 
        LCK_MTX_ASSERT(&p->p_dtrace_sprlock, LCK_MTX_ASSERT_OWNED);
        LCK_MTX_ASSERT(&p->p_mlock, LCK_MTX_ASSERT_OWNED);
 


@@ -267,7 +279,8 @@ dtrace_ptss_enable(struct proc* p) {
  * It assumes the sprlock is held, and the proc_lock is not.
  */
 void
  * It assumes the sprlock is held, and the proc_lock is not.
  */
 void

-dtrace_ptss_exec_exit(struct proc* p) {
+dtrace_ptss_exec_exit(struct proc* p)
+{

        /*
         * Should hold sprlock to touch the pages list. Must not
         * hold the proc lock to avoid deadlock.
        /*
         * Should hold sprlock to touch the pages list. Must not
         * hold the proc lock to avoid deadlock.


@@ -282,11 +295,11 @@ dtrace_ptss_exec_exit(struct proc* p) {
 
        while (temp != NULL) {
                struct dtrace_ptss_page* next = temp->next;
 
        while (temp != NULL) {
                struct dtrace_ptss_page* next = temp->next;

-               
+

                // Do we need to specifically mach_vm_deallocate the user pages?
                // This can be called when the process is exiting, I believe the proc's
                // vm_map_t may already be toast.
                // Do we need to specifically mach_vm_deallocate the user pages?
                // This can be called when the process is exiting, I believe the proc's
                // vm_map_t may already be toast.

-               
+

                // Must be certain to free the kernel memory!
                _FREE(temp, M_TEMP);
                temp = next;
                // Must be certain to free the kernel memory!
                _FREE(temp, M_TEMP);
                temp = next;


@@ -303,7 +316,8 @@ dtrace_ptss_exec_exit(struct proc* p) {
  * Parent and child sprlock should be held, and proc_lock must NOT be held.
  */
 void
  * Parent and child sprlock should be held, and proc_lock must NOT be held.
  */
 void

-dtrace_ptss_fork(struct proc* parent, struct proc* child) {
+dtrace_ptss_fork(struct proc* parent, struct proc* child)
+{

        // The child should not have any pages/entries allocated at this point.
        // ASSERT(child->p_dtrace_ptss_pages == NULL);
        // ASSERT(child->p_dtrace_ptss_free_list == NULL);
        // The child should not have any pages/entries allocated at this point.
        // ASSERT(child->p_dtrace_ptss_pages == NULL);
        // ASSERT(child->p_dtrace_ptss_free_list == NULL);


@@ -323,7 +337,7 @@ dtrace_ptss_fork(struct proc* parent, struct proc* child) {
        // Get page list from *PARENT*
        struct dtrace_ptss_page* temp = parent->p_dtrace_ptss_pages;
 
        // Get page list from *PARENT*
        struct dtrace_ptss_page* temp = parent->p_dtrace_ptss_pages;
 

-       while (temp != NULL) {          
+       while (temp != NULL) {

                // Freeing the page in the *CHILD*
                dtrace_ptss_free_page(child, temp);
 
                // Freeing the page in the *CHILD*
                dtrace_ptss_free_page(child, temp);