Add a basic NVMe driver support to serenity
based on NVMe spec 1.4.
The driver can support multiple NVMe drives (subsystems).
But in a NVMe drive, the driver can support one controller
with multiple namespaces.
Each core will get a separate NVMe Queue.
As the system lacks MSI support, PIN based interrupts are
used for IO.
Tested the NVMe support by replacing IDE driver
with the NVMe driver :^)
This is really a basic support for AHCI hotplug events, so we know how
to add a node representing the device in /sys/dev/block and removing it
according to the event type (insertion/removal).
This change doesn't take into account what happens if the device was
mounted or a read/write operation is being handled.
For this to work correctly, StorageManagement now uses the Singleton
container, as it might be accessed simultaneously from many CPUs
for hotplug events. DiskPartition holds a WeakPtr instead of a RefPtr,
to allow removal of a StorageDevice object from the heap.
StorageDevices are now stored and being referenced to via an
IntrusiveList to make it easier to remove them on hotplug event.
In future changes, all of the stated above might change, but for now,
this commit represents the least amount of changes to make everything
to work correctly.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
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.
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.
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.
System components that need an IRQ handling are now inheriting the
InterruptHandler class.
In addition to that, the initialization process of PATAChannel was
changed to fit the changes.
PATAChannel, E1000NetworkAdapter and RTL8139NetworkAdapter are now
inheriting from PCI::Device instead of InterruptHandler directly.
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.
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.