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Kernel+LibC: Pass 64-bit integers in syscalls by value

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Now that support for 32-bit x86 has been removed, we don't have to worry
about the top half of `off_t`/`u64` values being chopped off when we try
to pass them in registers. Therefore, we no longer need the workaround
of pointers to stack-allocated values to syscalls.

Note that this changes the system call ABI, so statically linked
programs will have to be re-linked.
This commit is contained in:
Daniel Bertalan 2023-08-11 10:47:31 +02:00
parent 87f4b0f1c2
commit 286984750e
12 changed files with 22 additions and 37 deletions
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5
Kernel/Syscalls/ftruncate.cpp
View file

@ -9,13 +9,10 @@
namespace Kernel {
// NOTE: The length is passed by pointer because off_t is 64bit,
// hence it can't be passed by register on 32bit platforms.
ErrorOr<FlatPtr> Process::sys$ftruncate(int fd, Userspace<off_t const*> userspace_length)
ErrorOr<FlatPtr> Process::sys$ftruncate(int fd, off_t length)
{
VERIFY_NO_PROCESS_BIG_LOCK(this);
TRY(require_promise(Pledge::stdio));
auto length = TRY(copy_typed_from_user(userspace_length));
if (length < 0)
return EINVAL;
auto description = TRY(open_file_description(fd));