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path: root/Kernel/Devices/ZeroDevice.h
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2020-12-27Kernel: Add a method to determine the desired permissions of a DeviceLiav A
This method will be used later in DevFS, to set the appropriate permissions for each device node.
2020-09-13Kernel: Make copy_to/from_user safe and remove unnecessary checksTom
Since the CPU already does almost all necessary validation steps for us, we don't really need to attempt to do this. Doing it ourselves doesn't really work very reliably, because we'd have to account for other processors modifying virtual memory, and we'd have to account for e.g. pages not being able to be allocated due to insufficient resources. So change the copy_to/from_user (and associated helper functions) to use the new safe_memcpy, which will return whether it succeeded or not. The only manual validation step needed (which the CPU can't perform for us) is making sure the pointers provided by user mode aren't pointing to kernel mappings. To make it easier to read/write from/to either kernel or user mode data add the UserOrKernelBuffer helper class, which will internally either use copy_from/to_user or directly memcpy, or pass the data through directly using a temporary buffer on the stack. Last but not least we need to keep syscall params trivial as we need to copy them from/to user mode using copy_from/to_user.
2020-08-04Kernel: Make File::write() and File::read() return KResultOr<size_t>Andreas Kling
Instead of returning a ssize_t where negative values mean error, we now return KResultOr<size_t> and use the error state to report errors exclusively.
2020-04-10Kernel: Add explicit offset parameter to File::read etcConrad Pankoff
2020-02-16Kernel: Move all code into the Kernel namespaceAndreas Kling
2020-01-18Meta: Add license header to source filesAndreas Kling
As suggested by Joshua, this commit adds the 2-clause BSD license as a comment block to the top of every source file. For the first pass, I've just added myself for simplicity. I encourage everyone to add themselves as copyright holders of any file they've added or modified in some significant way. If I've added myself in error somewhere, feel free to replace it with the appropriate copyright holder instead. Going forward, all new source files should include a license header.
2019-11-04Kernel: Make File's can_read/can_write take a const FileDescription&Andreas Kling
Asking a File if we could possibly read or write it will never mutate the asking FileDescription&, so it should be const.
2019-07-03AK: Rename the common integer typedefs to make it obvious what they are.Andreas Kling
These types can be picked up by including <AK/Types.h>: * u8, u16, u32, u64 (unsigned) * i8, i16, i32, i64 (signed)
2019-06-07Kernel: Rename FileDescriptor to FileDescription.Andreas Kling
After reading a bunch of POSIX specs, I've learned that a file descriptor is the number that refers to a file description, not the description itself. So this patch renames FileDescriptor to FileDescription, and Process now has FileDescription* file_description(int fd).
2019-05-28Add clang-format fileRobin Burchell
Also run it across the whole tree to get everything using the One True Style. We don't yet run this in an automated fashion as it's a little slow, but there is a snippet to do so in makeall.sh.
2019-04-29Kernel: Have File virtuals take a FileDescriptor& rather than a Process&.Andreas Kling
This will allow us to implement different behaviors depending on the role of the descriptor a File is being accessed through.
2019-04-03Kernel: Move devices into Kernel/Devices/.Andreas Kling