summaryrefslogtreecommitdiff
path: root/Kernel/Devices/BlockDevice.cpp
AgeCommit message (Collapse)Author
2020-11-12Kernel: Implement an asynchronous device request stackTom
This allows issuing asynchronous requests for devices and waiting on the completion of the request. The requests can cascade into multiple sub-requests. Since IRQs may complete at any time, if the current process is no longer the same that started the process, we need to swich the paging context before accessing user buffers. Change the PATA driver to use this model.
2020-11-04Revert "Kernel: Implement an asynchronous device request stack"Andreas Kling
This reverts commit 2fd5ce1eb06e5cbbb180cba64a567e99f0cd846c. This broke booting without SMP. (PR was #3921)
2020-11-04Kernel: Implement an asynchronous device request stackTom
This allows issuing asynchronous requests for devices and waiting on the completion of the request. The requests can cascade into multiple sub-requests. Since IRQs may complete at any time, if the current process is no longer the same that started the process, we need to swich the paging context before accessing user buffers. Change the PATA driver to use this model.
2020-11-04Kernel: Remove dead code from BlockDeviceTom
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.
2020-02-16Kernel: Move all code into the Kernel namespaceAndreas Kling
2020-02-08Kernel: Merge unnecessary DiskDevice class into BlockDeviceAndreas 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.
2019-04-03Kernel: Move devices into Kernel/Devices/.Andreas Kling