Kernel: Remove unused syscall sys$minherit()

This is no longer used. We can bring it back the day we need it.

Kernel/API/Syscall.h

@@ -186,7 +186,6 @@ namespace Kernel {
     S(shutdown)               \
     S(get_stack_bounds)       \
     S(ptrace)                 \
-    S(minherit)               \
     S(sendfd)                 \
     S(recvfd)                 \
     S(sysconf)                \

Kernel/Process.h

@@ -259,7 +259,6 @@ public:
     int sys$set_mmap_name(Userspace<const Syscall::SC_set_mmap_name_params*>);
     int sys$mprotect(void*, size_t, int prot);
     int sys$madvise(void*, size_t, int advice);
-    int sys$minherit(void*, size_t, int inherit);
     int sys$purge(int mode);
     int sys$select(const Syscall::SC_select_params*);
     int sys$poll(Userspace<const Syscall::SC_poll_params*>);

Kernel/Syscalls/mmap.cpp

@@ -306,32 +306,6 @@ int Process::sys$madvise(void* address, size_t size, int advice)
     return -EINVAL;
 }
 
-int Process::sys$minherit(void* address, size_t size, int inherit)
-{
-    REQUIRE_PROMISE(stdio);
-
-    auto* region = find_region_from_range({ VirtualAddress(address), size });
-    if (!region)
-        return -EINVAL;
-
-    if (!region->is_mmap())
-        return -EINVAL;
-
-    if (region->is_shared())
-        return -EINVAL;
-
-    if (!region->vmobject().is_anonymous())
-        return -EINVAL;
-
-    switch (inherit) {
-    case MAP_INHERIT_ZERO:
-        region->set_inherit_mode(Region::InheritMode::ZeroedOnFork);
-        return 0;
-    }
-
-    return -EINVAL;
-}
-
 int Process::sys$set_mmap_name(Userspace<const Syscall::SC_set_mmap_name_params*> user_params)
 {
     REQUIRE_PROMISE(stdio);

Kernel/UnixTypes.h

@@ -104,8 +104,6 @@ enum {
 #define MADV_SET_NONVOLATILE 0x200
 #define MADV_GET_VOLATILE 0x400
 
-#define MAP_INHERIT_ZERO 1
-
 #define F_DUPFD 0
 #define F_GETFD 1
 #define F_SETFD 2

Kernel/VM/Region.cpp

@@ -93,19 +93,6 @@ OwnPtr<Region> Region::clone(Process& new_owner)
     ASSERT(Process::current());
 
     ScopedSpinLock lock(s_mm_lock);
-    if (m_inherit_mode == InheritMode::ZeroedOnFork) {
-        ASSERT(m_mmap);
-        ASSERT(!m_shared);
-        ASSERT(vmobject().is_anonymous());
-        auto new_vmobject = AnonymousVMObject::create_with_size(size(), AllocationStrategy::Reserve); // TODO: inherit committed non-volatile areas?
-        if (!new_vmobject)
-            return {};
-        auto zeroed_region = Region::create_user_accessible(&new_owner, m_range, new_vmobject.release_nonnull(), 0, m_name, m_access);
-        zeroed_region->copy_purgeable_page_ranges(*this);
-        zeroed_region->set_mmap(m_mmap);
-        zeroed_region->set_inherit_mode(m_inherit_mode);
-        return zeroed_region;
-    }
 
     if (m_shared) {
         ASSERT(!m_stack);

Kernel/VM/Region.h

@@ -56,11 +56,6 @@ public:
         Execute = 4,
     };
 
-    enum class InheritMode {
-        Default,
-        ZeroedOnFork,
-    };
-
     static NonnullOwnPtr<Region> create_user_accessible(Process*, const Range&, NonnullRefPtr<VMObject>, size_t offset_in_vmobject, const StringView& name, u8 access, bool cacheable = true, bool shared = false);
     static NonnullOwnPtr<Region> create_kernel_only(const Range&, NonnullRefPtr<VMObject>, size_t offset_in_vmobject, const StringView& name, u8 access, bool cacheable = true);
 
@@ -227,8 +222,6 @@ public:
     // NOTE: These are public so we can make<> them.
     Region(const Range&, NonnullRefPtr<VMObject>, size_t offset_in_vmobject, const String&, u8 access, bool cacheable, bool kernel, bool shared);
 
-    void set_inherit_mode(InheritMode inherit_mode) { m_inherit_mode = inherit_mode; }
-
     bool remap_vmobject_page_range(size_t page_index, size_t page_count);
 
     bool is_volatile(VirtualAddress vaddr, size_t size) const;
@@ -270,7 +263,6 @@ private:
     NonnullRefPtr<VMObject> m_vmobject;
     String m_name;
     u8 m_access { 0 };
-    InheritMode m_inherit_mode : 3 { InheritMode::Default };
     bool m_shared : 1 { false };
     bool m_user_accessible : 1 { false };
     bool m_cacheable : 1 { false };

Userland/Libraries/LibC/mman.cpp

@@ -93,12 +93,6 @@ int madvise(void* address, size_t size, int advice)
     __RETURN_WITH_ERRNO(rc, rc, -1);
 }
 
-int minherit(void* address, size_t size, int inherit)
-{
-    int rc = syscall(SC_minherit, address, size, inherit);
-    __RETURN_WITH_ERRNO(rc, rc, -1);
-}
-
 void* allocate_tls(size_t size)
 {
     int rc = syscall(SC_allocate_tls, size);

Userland/Libraries/LibC/mman.h

@@ -49,8 +49,6 @@
 #define MADV_SET_NONVOLATILE 0x200
 #define MADV_GET_VOLATILE 0x400
 
-#define MAP_INHERIT_ZERO 1
-
 __BEGIN_DECLS
 
 void* mmap(void* addr, size_t, int prot, int flags, int fd, off_t);
@@ -61,7 +59,6 @@ int munmap(void*, size_t);
 int mprotect(void*, size_t, int prot);
 int set_mmap_name(void*, size_t, const char*);
 int madvise(void*, size_t, int advice);
-int minherit(void*, size_t, int inherit);
 void* allocate_tls(size_t);
 
 __END_DECLS