Kernel+Userland: Remove shared buffers (shbufs)

All users of this mechanism have been switched to anonymous files and
passing file descriptors with sendfd()/recvfd().

Shbufs got us where we are today, but it's time we say good-bye to them
and welcome a much more idiomatic replacement. :^)
This commit is contained in:
Andreas Kling 2021-01-17 08:51:41 +01:00
parent 2cd16778b5
commit bf0719092f
28 changed files with 2 additions and 1022 deletions

View file

@ -46,12 +46,6 @@ constexpr bool debug_scheduler_runnable = true;
constexpr bool debug_scheduler_runnable = false;
#endif
#ifdef SHARED_BUFFER_DEBUG
constexpr bool debug_shared_buffer = true;
#else
constexpr bool debug_shared_buffer = false;
#endif
#ifdef THREAD_DEBUG
constexpr bool debug_thread = true;
#else

View file

@ -38,7 +38,6 @@ class JsonArray;
class JsonObject;
class JsonValue;
class LogStream;
class SharedBuffer;
class StackInfo;
class String;
class StringBuilder;
@ -169,7 +168,6 @@ using AK::OutputStream;
using AK::OwnPtr;
using AK::ReadonlyBytes;
using AK::RefPtr;
using AK::SharedBuffer;
using AK::SinglyLinkedList;
using AK::Span;
using AK::StackInfo;

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@ -1,168 +0,0 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/SharedBuffer.h>
#include <stdio.h>
#if defined(__serenity__)
# include <Kernel/API/Syscall.h>
# include <serenity.h>
#else
# include <AK/String.h>
# include <fcntl.h>
# include <sys/mman.h>
static String shbuf_shm_name(int shbuf_id)
{
return String::formatted("/serenity-shm:{}", shbuf_id);
}
#endif
namespace AK {
RefPtr<SharedBuffer> SharedBuffer::create_with_size(int size)
{
#if defined(__serenity__)
void* data;
int shbuf_id = shbuf_create(size, &data);
if (shbuf_id < 0) {
perror("shbuf_create");
return nullptr;
}
#else
// Not atomic, so don't create shared buffers from many threads too hard under lagom.
static unsigned g_shm_id = 0;
int shbuf_id = (getpid() << 8) | (g_shm_id++);
int fd = shm_open(shbuf_shm_name(shbuf_id).characters(), O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
if (fd < 0) {
perror("shm_open");
return nullptr;
}
if (ftruncate(fd, size) < 0) {
perror("ftruncate");
return nullptr;
}
void* data = mmap(nullptr, size + sizeof(size_t), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
if (data == MAP_FAILED) {
perror("mmap");
return nullptr;
}
size_t* size_data = reinterpret_cast<size_t*>(data);
*size_data = size;
data = reinterpret_cast<u8*>(data) + sizeof(size_t);
if (close(fd) < 0) {
perror("close");
return nullptr;
}
#endif
return adopt(*new SharedBuffer(shbuf_id, size, data));
}
bool SharedBuffer::share_with([[maybe_unused]] pid_t peer)
{
#if defined(__serenity__)
int ret = shbuf_allow_pid(shbuf_id(), peer);
if (ret < 0) {
perror("shbuf_allow_pid");
return false;
}
#endif
return true;
}
RefPtr<SharedBuffer> SharedBuffer::create_from_shbuf_id(int shbuf_id)
{
#if defined(__serenity__)
size_t size = 0;
void* data = shbuf_get(shbuf_id, &size);
if (data == (void*)-1)
return nullptr;
#else
int fd = shm_open(shbuf_shm_name(shbuf_id).characters(), O_RDWR, S_IRUSR | S_IWUSR);
if (fd < 0) {
perror("shm_open");
return nullptr;
}
void* data = mmap(nullptr, sizeof(size_t), PROT_READ, MAP_SHARED, fd, 0);
if (data == MAP_FAILED) {
perror("mmap");
return nullptr;
}
size_t* size_data = reinterpret_cast<size_t*>(data);
size_t size = *size_data;
if (munmap(data, sizeof(size_t)) < 0) {
perror("munmap");
return nullptr;
}
data = mmap(nullptr, size + sizeof(size_t), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
if (data == MAP_FAILED) {
perror("mmap");
return nullptr;
}
data = reinterpret_cast<u8*>(data) + sizeof(size_t);
if (close(fd) < 0) {
perror("close");
return nullptr;
}
#endif
return adopt(*new SharedBuffer(shbuf_id, size, data));
}
SharedBuffer::SharedBuffer(int shbuf_id, int size, void* data)
: m_shbuf_id(shbuf_id)
, m_size(size)
, m_data(data)
{
}
SharedBuffer::~SharedBuffer()
{
if (m_shbuf_id >= 0) {
#if defined(__serenity__)
int rc = shbuf_release(m_shbuf_id);
if (rc < 0) {
perror("shbuf_release");
}
#else
if (munmap(reinterpret_cast<u8*>(m_data) - sizeof(size_t), m_size + sizeof(size_t)) < 0)
perror("munmap");
if (shm_unlink(shbuf_shm_name(m_shbuf_id).characters()) < 0)
perror("unlink");
#endif
}
}
}

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@ -1,68 +0,0 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
namespace AK {
class SharedBuffer : public RefCounted<SharedBuffer> {
public:
static RefPtr<SharedBuffer> create_with_size(int);
static RefPtr<SharedBuffer> create_from_shbuf_id(int);
~SharedBuffer();
bool share_with(pid_t);
int shbuf_id() const { return m_shbuf_id; }
int size() const { return m_size; }
template<typename T>
T* data()
{
static_assert(IsVoid<T>::value || is_trivial<T>());
return (T*)m_data;
}
template<typename T>
const T* data() const
{
static_assert(IsVoid<T>::value || is_trivial<T>());
return (const T*)m_data;
}
private:
SharedBuffer(int shbuf_id, int size, void*);
int m_shbuf_id { -1 };
int m_size { 0 };
void* m_data { nullptr };
};
}
using AK::SharedBuffer;

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@ -45,7 +45,6 @@ If the process later attempts to use any system functionality it has previously
* `dpath`: Creating new device files
* `chown`: Changing file owner/group
* `fattr`: Changing file attributes/permissions
* `shared_buffer`: Shared memory buffers (\*)
* `chroot`: The [`chroot(2)`](chroot.md) syscall (\*)
* `video`: May use [`ioctl(2)`](ioctl.md) and [`mmap(2)`](mmap.md) on framebuffer video devices
* `settime`: Changing the system time and date

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@ -1,28 +0,0 @@
## Name
shbuf\_allow\_pid - allow another process to map a shareable buffer
## Synopsis
```**c++
#include <SharedBuffer.h>
int shbuf_allow_pid(int shbuf_id, pid_t peer_pid);
```
## Description
Gives the process with PID `peer_pid` permission to map the shareable buffer with ID `shbuf_id`.
## Return value
On success, returns 0. Otherwise, returns -1 and `errno` is set.
## Errors
* `EINVAL`: `peer_pid` is invalid, or `shbuf_id` is not a valid ID.
* `EPERM`: The calling process does not have access to the buffer with `shbuf_id`.
* `ESRCH`: No process with PID `peer_pid` is found.
## See also
* [`shbuf_create`(2)](shbuf_create.md)

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@ -1,27 +0,0 @@
## Name
shbuf\_create - create a shareable memory buffer
## Synopsis
```**c++
#include <SharedBuffer.h>
int shbuf_create(int size, void** buffer);
```
## Description
Creates a new memory region that can be shared with other processes. The region is only accessible to the calling process by default.
## Return value
If a region is successfully created, `shbuf_create()` stores a pointer to the memory in `buffer` and returns a buffer ID. Otherwise, it returns -1 and sets `errno` to describe the error.
## Errors
* `EINVAL`: `size` is zero or negative.
* `EFAULT`: `buffer` is not a valid address.
## See also
* [`shbuf_allow_pid`(2)](shbuf_allow_pid.md)

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@ -121,10 +121,6 @@ namespace Kernel {
S(accept) \
S(listen) \
S(connect) \
S(shbuf_create) \
S(shbuf_allow_pid) \
S(shbuf_get) \
S(shbuf_release) \
S(link) \
S(chown) \
S(fchmod) \

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@ -101,7 +101,6 @@ set(KERNEL_SOURCES
RTC.cpp
Random.cpp
Scheduler.cpp
SharedBuffer.cpp
StdLib.cpp
Syscall.cpp
Syscalls/anon_create.cpp
@ -157,7 +156,6 @@ set(KERNEL_SOURCES
Syscalls/setkeymap.cpp
Syscalls/setpgid.cpp
Syscalls/setuid.cpp
Syscalls/shbuf.cpp
Syscalls/shutdown.cpp
Syscalls/sigaction.cpp
Syscalls/socket.cpp

View file

@ -60,7 +60,6 @@ class RangeAllocator;
class Region;
class Scheduler;
class SchedulerPerProcessorData;
class SharedBuffer;
class Socket;
template<typename BaseType>
class SpinLock;

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@ -45,10 +45,10 @@
#include <Kernel/PerformanceEventBuffer.h>
#include <Kernel/Process.h>
#include <Kernel/RTC.h>
#include <Kernel/SharedBuffer.h>
#include <Kernel/StdLib.h>
#include <Kernel/TTY/TTY.h>
#include <Kernel/Thread.h>
#include <Kernel/VM/AnonymousVMObject.h>
#include <Kernel/VM/PageDirectory.h>
#include <Kernel/VM/PrivateInodeVMObject.h>
#include <Kernel/VM/ProcessPagingScope.h>
@ -644,7 +644,6 @@ void Process::finalize()
m_dead = true;
disown_all_shared_buffers();
{
// FIXME: PID/TID BUG
if (auto parent_thread = Thread::from_tid(m_ppid.value())) {

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@ -80,8 +80,7 @@ extern VirtualAddress g_return_to_ring3_from_signal_trampoline;
__ENUMERATE_PLEDGE_PROMISE(accept) \
__ENUMERATE_PLEDGE_PROMISE(settime) \
__ENUMERATE_PLEDGE_PROMISE(sigaction) \
__ENUMERATE_PLEDGE_PROMISE(setkeymap) \
__ENUMERATE_PLEDGE_PROMISE(shared_buffer)
__ENUMERATE_PLEDGE_PROMISE(setkeymap)
enum class Pledge : u32 {
#define __ENUMERATE_PLEDGE_PROMISE(x) x,
@ -334,10 +333,6 @@ public:
int sys$get_thread_name(pid_t tid, Userspace<char*> buffer, size_t buffer_size);
int sys$rename(Userspace<const Syscall::SC_rename_params*>);
int sys$mknod(Userspace<const Syscall::SC_mknod_params*>);
int sys$shbuf_create(int, void** buffer);
int sys$shbuf_allow_pid(int, pid_t peer_pid);
void* sys$shbuf_get(int shbuf_id, Userspace<size_t*> size);
int sys$shbuf_release(int shbuf_id);
int sys$halt();
int sys$reboot();
int sys$realpath(Userspace<const Syscall::SC_realpath_params*>);
@ -530,7 +525,6 @@ private:
KResultOr<RefPtr<FileDescription>> find_elf_interpreter_for_executable(const String& path, const Elf32_Ehdr& elf_header, int nread, size_t file_size);
int alloc_fd(int first_candidate_fd = 0);
void disown_all_shared_buffers();
KResult do_kill(Process&, int signal);
KResult do_killpg(ProcessGroupID pgrp, int signal);

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@ -1,188 +0,0 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Debug.h>
#include <AK/Singleton.h>
#include <Kernel/Process.h>
#include <Kernel/SharedBuffer.h>
//#define SHARED_BUFFER_DEBUG
namespace Kernel {
static AK::Singleton<Lockable<HashMap<int, NonnullOwnPtr<SharedBuffer>>>> s_map;
Lockable<HashMap<int, NonnullOwnPtr<SharedBuffer>>>& shared_buffers()
{
return *s_map;
}
void SharedBuffer::sanity_check(const char* what)
{
LOCKER(shared_buffers().lock(), Lock::Mode::Shared);
unsigned found_refs = 0;
for (const auto& ref : m_refs)
found_refs += ref.count;
if (found_refs != m_total_refs) {
dbgln("{} sanity -- SharedBuffer({}) id: {} has total refs {} but we found {}",
what,
this,
m_shbuf_id,
m_total_refs,
found_refs);
for (const auto& ref : m_refs)
dbgln(" ref from pid {}: reference count {}", ref.pid.value(), ref.count);
ASSERT_NOT_REACHED();
}
}
bool SharedBuffer::is_shared_with(ProcessID peer_pid) const
{
LOCKER(shared_buffers().lock(), Lock::Mode::Shared);
for (auto& ref : m_refs) {
if (ref.pid == peer_pid) {
return true;
}
}
return false;
}
void* SharedBuffer::ref_for_process_and_get_address(Process& process)
{
LOCKER(shared_buffers().lock());
ASSERT(is_shared_with(process.pid()));
for (auto& ref : m_refs) {
if (ref.pid == process.pid()) {
if (!ref.region) {
auto region_or_error = process.allocate_region_with_vmobject(VirtualAddress(), size(), m_vmobject, 0, "SharedBuffer", PROT_READ | (m_writable ? PROT_WRITE : 0), true);
if (region_or_error.is_error())
return (void*)region_or_error.error().error();
ref.region = region_or_error.value();
}
ref.count++;
m_total_refs++;
sanity_check("ref_for_process_and_get_address");
return ref.region.unsafe_ptr()->vaddr().as_ptr(); // TODO: Region needs to be RefCounted!
}
}
ASSERT_NOT_REACHED();
}
void SharedBuffer::share_with(ProcessID peer_pid)
{
LOCKER(shared_buffers().lock());
for (auto& ref : m_refs) {
if (ref.pid == peer_pid) {
// don't increment the reference count yet; let them shbuf_get it first.
sanity_check("share_with (old ref)");
return;
}
}
m_refs.append(Reference(peer_pid));
sanity_check("share_with (new ref)");
}
void SharedBuffer::share_all_shared_buffers(Process& from_process, Process& with_process)
{
LOCKER(shared_buffers().lock());
for (auto& shbuf : shared_buffers().resource()) {
auto& shared_buffer = *shbuf.value;
// We need to clone all references (including for global shared buffers),
// and the reference counts as well.
for (auto& ref : shared_buffer.m_refs) {
if (ref.pid == from_process.pid()) {
auto ref_count = ref.count;
shared_buffer.m_refs.append(Reference(with_process.pid(), ref_count));
// NOTE: ref may become invalid after we appended!
shared_buffer.m_total_refs += ref_count;
break;
}
}
}
}
void SharedBuffer::deref_for_process(Process& process)
{
LOCKER(shared_buffers().lock());
for (size_t i = 0; i < m_refs.size(); ++i) {
auto& ref = m_refs[i];
if (ref.pid == process.pid()) {
ASSERT(ref.count > 0);
ref.count--;
ASSERT(m_total_refs > 0);
m_total_refs--;
if (ref.count == 0) {
dbgln<debug_shared_buffer>("Releasing shared buffer reference on {} of size {} by PID {}", m_shbuf_id, size(), process.pid().value());
process.deallocate_region(*ref.region.unsafe_ptr()); // TODO: Region needs to be RefCounted!
dbgln<debug_shared_buffer>("Released shared buffer reference on {} of size {} by PID {}", m_shbuf_id, size(), process.pid().value());
sanity_check("deref_for_process");
destroy_if_unused();
return;
}
return;
}
}
ASSERT_NOT_REACHED();
}
bool SharedBuffer::disown(ProcessID pid)
{
LOCKER(shared_buffers().lock());
for (size_t i = 0; i < m_refs.size(); ++i) {
auto& ref = m_refs[i];
if (ref.pid == pid) {
dbgln<debug_shared_buffer>("Disowning shared buffer {} of size {} by PID {}", m_shbuf_id, size(), pid.value());
ASSERT(m_total_refs >= ref.count);
m_total_refs -= ref.count;
m_refs.unstable_take(i);
dbgln<debug_shared_buffer>("Disowned shared buffer {} of size {} by PID {}", m_shbuf_id, size(), pid.value());
destroy_if_unused();
break;
}
}
return m_total_refs == 0;
}
void SharedBuffer::destroy_if_unused()
{
LOCKER(shared_buffers().lock());
sanity_check("destroy_if_unused");
if (m_total_refs == 0) {
dbgln<debug_shared_buffer>("Destroying unused SharedBuffer({}) id={}", this, m_shbuf_id);
auto count_before = shared_buffers().resource().size();
shared_buffers().resource().remove(m_shbuf_id);
ASSERT(count_before != shared_buffers().resource().size());
}
}
}

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@ -1,87 +0,0 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Debug.h>
#include <AK/OwnPtr.h>
#include <AK/WeakPtr.h>
#include <Kernel/VM/AnonymousVMObject.h>
#include <Kernel/VM/MemoryManager.h>
namespace Kernel {
class SharedBuffer {
private:
struct Reference {
Reference(ProcessID pid, unsigned count = 0)
: pid(pid)
, count(count)
{
}
ProcessID pid;
unsigned count { 0 };
WeakPtr<Region> region;
};
public:
SharedBuffer(int id, NonnullRefPtr<AnonymousVMObject>&& vmobject)
: m_shbuf_id(id)
, m_vmobject(move(vmobject))
{
dbgln<debug_shared_buffer>("Created shared buffer {} of size {}", m_shbuf_id, size());
}
~SharedBuffer()
{
dbgln<debug_shared_buffer>("Destroyed shared buffer {} of size {}", m_shbuf_id, size());
}
void sanity_check(const char* what);
bool is_shared_with(ProcessID peer_pid) const;
void* ref_for_process_and_get_address(Process& process);
void share_with(ProcessID peer_pid);
void deref_for_process(Process& process);
bool disown(ProcessID pid);
static void share_all_shared_buffers(Process& from_process, Process& with_process);
size_t size() const { return m_vmobject->size(); }
void destroy_if_unused();
AnonymousVMObject& vmobject() { return m_vmobject; }
const AnonymousVMObject& vmobject() const { return m_vmobject; }
int id() const { return m_shbuf_id; }
private:
int m_shbuf_id { -1 };
bool m_writable { true };
NonnullRefPtr<AnonymousVMObject> m_vmobject;
Vector<Reference, 2> m_refs;
unsigned m_total_refs { 0 };
};
Lockable<HashMap<int, NonnullOwnPtr<SharedBuffer>>>& shared_buffers();
}

View file

@ -522,8 +522,6 @@ int Process::do_exec(NonnullRefPtr<FileDescription> main_program_description, Ve
m_region_lookup_cache = {};
disown_all_shared_buffers();
set_dumpable(!executable_is_setid);
for (size_t i = 0; i < m_fds.size(); ++i) {

View file

@ -27,7 +27,6 @@
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/Process.h>
#include <Kernel/SharedBuffer.h>
#include <Kernel/VM/Region.h>
//#define FORK_DEBUG
@ -80,8 +79,6 @@ pid_t Process::sys$fork(RegisterState& regs)
dbgln("fork: child will begin executing at {:04x}:{:08x} with stack {:04x}:{:08x}, kstack {:04x}:{:08x}", child_tss.cs, child_tss.eip, child_tss.ss, child_tss.esp, child_tss.ss0, child_tss.esp0);
#endif
SharedBuffer::share_all_shared_buffers(*this, *child);
{
ScopedSpinLock lock(m_lock);
for (auto& region : m_regions) {

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@ -26,7 +26,6 @@
#include <AK/Types.h>
#include <Kernel/Process.h>
#include <Kernel/SharedBuffer.h>
namespace Kernel {

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@ -1,137 +0,0 @@
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <Kernel/Process.h>
#include <Kernel/SharedBuffer.h>
//#define SHARED_BUFFER_DEBUG
namespace Kernel {
void Process::disown_all_shared_buffers()
{
LOCKER(shared_buffers().lock());
Vector<SharedBuffer*, 32> buffers_to_disown;
for (auto& it : shared_buffers().resource())
buffers_to_disown.append(it.value.ptr());
for (auto* shared_buffer : buffers_to_disown) {
if (shared_buffer->disown(m_pid)) {
shared_buffers().resource().remove(shared_buffer->id());
delete shared_buffer;
}
}
}
int Process::sys$shbuf_create(int size, void** buffer)
{
REQUIRE_PROMISE(shared_buffer);
if (!size || size < 0)
return -EINVAL;
size = PAGE_ROUND_UP(size);
auto vmobject = AnonymousVMObject::create_with_size(size, AllocationStrategy::Reserve);
if (!vmobject)
return -ENOMEM;
LOCKER(shared_buffers().lock());
static int s_next_shbuf_id;
int shbuf_id = ++s_next_shbuf_id;
auto shared_buffer = make<SharedBuffer>(shbuf_id, vmobject.release_nonnull());
shared_buffer->share_with(m_pid);
void* address = shared_buffer->ref_for_process_and_get_address(*this);
if (!copy_to_user(buffer, &address))
return -EFAULT;
ASSERT((int)shared_buffer->size() >= size);
#ifdef SHARED_BUFFER_DEBUG
klog() << "Created shared buffer " << shbuf_id << " @ " << buffer << " (" << size << " bytes, vmobject is " << shared_buffer->size() << ")";
#endif
shared_buffers().resource().set(shbuf_id, move(shared_buffer));
return shbuf_id;
}
int Process::sys$shbuf_allow_pid(int shbuf_id, pid_t peer_pid)
{
REQUIRE_PROMISE(shared_buffer);
if (!peer_pid || peer_pid < 0 || ProcessID(peer_pid) == m_pid)
return -EINVAL;
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
{
ScopedSpinLock lock(g_processes_lock);
auto peer = Process::from_pid(peer_pid);
if (!peer)
return -ESRCH;
}
shared_buffer.share_with(peer_pid);
return 0;
}
int Process::sys$shbuf_release(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Releasing shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
shared_buffer.deref_for_process(*this);
return 0;
}
void* Process::sys$shbuf_get(int shbuf_id, Userspace<size_t*> user_size)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return (void*)-EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return (void*)-EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Retaining shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
if (user_size) {
size_t size = shared_buffer.size();
if (!copy_to_user(user_size, &size))
return (void*)-EFAULT;
}
return shared_buffer.ref_for_process_and_get_address(*this);
}
}

View file

@ -135,7 +135,6 @@ add_compile_definitions("SCHEDULER_DEBUG")
add_compile_definitions("SCHEDULER_RUNNABLE_DEBUG")
add_compile_definitions("SELECTION_DEBUG")
add_compile_definitions("SERVICE_DEBUG")
add_compile_definitions("SHARED_BUFFER_DEBUG")
add_compile_definitions("SH_DEBUG")
add_compile_definitions("SIGNAL_DEBUG")
add_compile_definitions("SLAVEPTY_DEBUG")

View file

@ -3,7 +3,6 @@ set(SOURCES
MallocTracer.cpp
MmapRegion.cpp
Region.cpp
SharedBufferRegion.cpp
SimpleRegion.cpp
SoftCPU.cpp
SoftMMU.cpp

View file

@ -26,7 +26,6 @@
#include "Emulator.h"
#include "MmapRegion.h"
#include "SharedBufferRegion.h"
#include "SimpleRegion.h"
#include "SoftCPU.h"
#include <AK/Format.h>
@ -385,14 +384,6 @@ u32 Emulator::virt_syscall(u32 function, u32 arg1, u32 arg2, u32 arg3)
return virt$ioctl(arg1, arg2, arg3);
case SC_get_dir_entries:
return virt$get_dir_entries(arg1, arg2, arg3);
case SC_shbuf_create:
return virt$shbuf_create(arg1, arg2);
case SC_shbuf_allow_pid:
return virt$shbuf_allow_pid(arg1, arg2);
case SC_shbuf_get:
return virt$shbuf_get(arg1, arg2);
case SC_shbuf_release:
return virt$shbuf_release(arg1);
case SC_profiling_enable:
return virt$profiling_enable(arg1);
case SC_profiling_disable:
@ -560,48 +551,6 @@ int Emulator::virt$recvfd(int socket)
return syscall(SC_recvfd, socket);
}
int Emulator::virt$shbuf_create(int size, FlatPtr buffer)
{
u8* host_data = nullptr;
int shbuf_id = syscall(SC_shbuf_create, size, &host_data);
if (shbuf_id < 0)
return shbuf_id;
FlatPtr address = allocate_vm(size, PAGE_SIZE);
auto region = SharedBufferRegion::create_with_shbuf_id(address, size, shbuf_id, host_data);
m_mmu.add_region(move(region));
m_mmu.copy_to_vm(buffer, &address, sizeof(address));
return shbuf_id;
}
FlatPtr Emulator::virt$shbuf_get(int shbuf_id, FlatPtr size_ptr)
{
size_t host_size = 0;
void* host_data = (void*)syscall(SC_shbuf_get, shbuf_id, &host_size);
if (host_data == (void*)-1)
return (FlatPtr)host_data;
FlatPtr address = allocate_vm(host_size, PAGE_SIZE);
auto region = SharedBufferRegion::create_with_shbuf_id(address, host_size, shbuf_id, (u8*)host_data);
m_mmu.add_region(move(region));
m_mmu.copy_to_vm(size_ptr, &host_size, sizeof(host_size));
return address;
}
int Emulator::virt$shbuf_allow_pid(int shbuf_id, pid_t peer_pid)
{
auto* region = m_mmu.shbuf_region(shbuf_id);
ASSERT(region);
return region->allow_pid(peer_pid);
}
int Emulator::virt$shbuf_release(int shbuf_id)
{
auto* region = m_mmu.shbuf_region(shbuf_id);
ASSERT(region);
auto rc = region->release();
m_mmu.remove_region(*region);
return rc;
}
int Emulator::virt$profiling_enable(pid_t pid)
{
return syscall(SC_profiling_enable, pid);

View file

@ -91,10 +91,6 @@ private:
int virt$stat(FlatPtr);
int virt$realpath(FlatPtr);
int virt$gethostname(FlatPtr, ssize_t);
int virt$shbuf_create(int size, FlatPtr buffer);
int virt$shbuf_allow_pid(int, pid_t peer_pid);
FlatPtr virt$shbuf_get(int shbuf_id, FlatPtr size);
int virt$shbuf_release(int shbuf_id);
int virt$profiling_enable(pid_t);
int virt$profiling_disable(pid_t);
int virt$disown(pid_t);

View file

@ -1,117 +0,0 @@
/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "SharedBufferRegion.h"
#include "Emulator.h"
#include <Kernel/API/Syscall.h>
#include <serenity.h>
#include <string.h>
#include <sys/mman.h>
namespace UserspaceEmulator {
NonnullOwnPtr<SharedBufferRegion> SharedBufferRegion::create_with_shbuf_id(u32 base, u32 size, int shbuf_id, u8* host_data)
{
return adopt_own(*new SharedBufferRegion(base, size, shbuf_id, host_data));
}
SharedBufferRegion::SharedBufferRegion(u32 base, u32 size, int shbuf_id, u8* host_data)
: Region(base, size)
, m_data(host_data)
, m_shbuf_id(shbuf_id)
{
m_shadow_data = (u8*)malloc(size);
memset(m_shadow_data, 1, size);
}
SharedBufferRegion::~SharedBufferRegion()
{
free(m_shadow_data);
}
ValueWithShadow<u8> SharedBufferRegion::read8(FlatPtr offset)
{
ASSERT(offset < size());
return { *reinterpret_cast<const u8*>(m_data + offset), *reinterpret_cast<const u8*>(m_shadow_data + offset) };
}
ValueWithShadow<u16> SharedBufferRegion::read16(u32 offset)
{
ASSERT(offset + 1 < size());
return { *reinterpret_cast<const u16*>(m_data + offset), *reinterpret_cast<const u16*>(m_shadow_data + offset) };
}
ValueWithShadow<u32> SharedBufferRegion::read32(u32 offset)
{
ASSERT(offset + 3 < size());
return { *reinterpret_cast<const u32*>(m_data + offset), *reinterpret_cast<const u32*>(m_shadow_data + offset) };
}
ValueWithShadow<u64> SharedBufferRegion::read64(u32 offset)
{
ASSERT(offset + 7 < size());
return { *reinterpret_cast<const u64*>(m_data + offset), *reinterpret_cast<const u64*>(m_shadow_data + offset) };
}
void SharedBufferRegion::write8(u32 offset, ValueWithShadow<u8> value)
{
ASSERT(offset < size());
*reinterpret_cast<u8*>(m_data + offset) = value.value();
*reinterpret_cast<u8*>(m_shadow_data + offset) = value.shadow();
}
void SharedBufferRegion::write16(u32 offset, ValueWithShadow<u16> value)
{
ASSERT(offset + 1 < size());
*reinterpret_cast<u16*>(m_data + offset) = value.value();
*reinterpret_cast<u16*>(m_shadow_data + offset) = value.shadow();
}
void SharedBufferRegion::write32(u32 offset, ValueWithShadow<u32> value)
{
ASSERT(offset + 3 < size());
*reinterpret_cast<u32*>(m_data + offset) = value.value();
*reinterpret_cast<u32*>(m_shadow_data + offset) = value.shadow();
}
void SharedBufferRegion::write64(u32 offset, ValueWithShadow<u64> value)
{
ASSERT(offset + 7 < size());
*reinterpret_cast<u64*>(m_data + offset) = value.value();
*reinterpret_cast<u64*>(m_shadow_data + offset) = value.shadow();
}
int SharedBufferRegion::allow_pid(pid_t pid)
{
return syscall(SC_shbuf_allow_pid, m_shbuf_id, pid);
}
int SharedBufferRegion::release()
{
return syscall(SC_shbuf_release, m_shbuf_id);
}
}

View file

@ -1,65 +0,0 @@
/*
* Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "SoftMMU.h"
#include <sys/mman.h>
namespace UserspaceEmulator {
class SharedBufferRegion final : public Region {
public:
static NonnullOwnPtr<SharedBufferRegion> create_with_shbuf_id(u32 base, u32 size, int shbuf_id, u8* shbuf_data);
virtual ~SharedBufferRegion() override;
virtual ValueWithShadow<u8> read8(u32 offset) override;
virtual ValueWithShadow<u16> read16(u32 offset) override;
virtual ValueWithShadow<u32> read32(u32 offset) override;
virtual ValueWithShadow<u64> read64(u32 offset) override;
virtual void write8(u32 offset, ValueWithShadow<u8>) override;
virtual void write16(u32 offset, ValueWithShadow<u16>) override;
virtual void write32(u32 offset, ValueWithShadow<u32>) override;
virtual void write64(u32 offset, ValueWithShadow<u64>) override;
virtual u8* data() override { return m_data; }
virtual u8* shadow_data() override { return m_shadow_data; }
int shbuf_id() const { return m_shbuf_id; }
int allow_pid(pid_t);
int release();
private:
SharedBufferRegion(u32 base, u32 size, int shbuf_id, u8* shbuf_data);
u8* m_data { nullptr };
u8* m_shadow_data { nullptr };
int m_shbuf_id { 0 };
};
}

View file

@ -28,7 +28,6 @@
#include "Emulator.h"
#include "MmapRegion.h"
#include "Report.h"
#include "SharedBufferRegion.h"
#include <AK/ByteBuffer.h>
#include <AK/Memory.h>
@ -43,10 +42,6 @@ void SoftMMU::add_region(NonnullOwnPtr<Region> region)
{
ASSERT(!find_region({ 0x23, region->base() }));
// FIXME: More sanity checks pls
if (is<SharedBufferRegion>(*region))
m_shbuf_regions.set(static_cast<SharedBufferRegion*>(region.ptr())->shbuf_id(), region.ptr());
size_t first_page_in_region = region->base() / PAGE_SIZE;
size_t last_page_in_region = (region->base() + region->size() - 1) / PAGE_SIZE;
for (size_t page = first_page_in_region; page <= last_page_in_region; ++page) {
@ -63,8 +58,6 @@ void SoftMMU::remove_region(Region& region)
m_page_to_region_map[first_page_in_region + i] = nullptr;
}
if (is<SharedBufferRegion>(region))
m_shbuf_regions.remove(static_cast<SharedBufferRegion&>(region).shbuf_id());
m_regions.remove_first_matching([&](auto& entry) { return entry.ptr() == &region; });
}
@ -238,11 +231,6 @@ ByteBuffer SoftMMU::copy_buffer_from_vm(const FlatPtr source, size_t size)
return buffer;
}
SharedBufferRegion* SoftMMU::shbuf_region(int shbuf_id)
{
return (SharedBufferRegion*)m_shbuf_regions.get(shbuf_id).value_or(nullptr);
}
bool SoftMMU::fast_fill_memory8(X86::LogicalAddress address, size_t size, ValueWithShadow<u8> value)
{
if (!size)

View file

@ -37,7 +37,6 @@
namespace UserspaceEmulator {
class Emulator;
class SharedBufferRegion;
class SoftMMU {
public:
@ -74,8 +73,6 @@ public:
void copy_from_vm(void* destination, const FlatPtr source, size_t);
ByteBuffer copy_buffer_from_vm(const FlatPtr source, size_t);
SharedBufferRegion* shbuf_region(int shbuf_id);
template<typename Callback>
void for_each_region(Callback callback)
{
@ -96,7 +93,6 @@ private:
OwnPtr<Region> m_tls_region;
NonnullOwnPtrVector<Region> m_regions;
HashMap<int, Region*> m_shbuf_regions;
};
}

View file

@ -79,34 +79,6 @@ int perf_event(int type, uintptr_t arg1, FlatPtr arg2)
__RETURN_WITH_ERRNO(rc, rc, -1);
}
void* shbuf_get(int shbuf_id, size_t* size)
{
ssize_t rc = syscall(SC_shbuf_get, shbuf_id, size);
if (rc < 0 && -rc < EMAXERRNO) {
errno = -rc;
return (void*)-1;
}
return (void*)rc;
}
int shbuf_release(int shbuf_id)
{
int rc = syscall(SC_shbuf_release, shbuf_id);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int shbuf_create(int size, void** buffer)
{
int rc = syscall(SC_shbuf_create, size, buffer);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int shbuf_allow_pid(int shbuf_id, pid_t peer_pid)
{
int rc = syscall(SC_shbuf_allow_pid, shbuf_id, peer_pid);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int get_stack_bounds(uintptr_t* user_stack_base, size_t* user_stack_size)
{
int rc = syscall(SC_get_stack_bounds, user_stack_base, user_stack_size);

View file

@ -33,11 +33,6 @@ __BEGIN_DECLS
int disown(pid_t);
int shbuf_create(int, void** buffer);
int shbuf_allow_pid(int, pid_t peer_pid);
void* shbuf_get(int shbuf_id, size_t* size);
int shbuf_release(int shbuf_id);
int module_load(const char* path, size_t path_length);
int module_unload(const char* name, size_t name_length);