In case multiple file descriptors in the `fd_set` were already readable
and/or writable when calling Thread::block<SelectBlocker>(), we would
only mark the first fd in the output sets instead of all relevant fd's.
The short-circuit code path when blocking isn't necessary must ensure
that unblock flags are collected for all file descriptors, not just the
first one encountered.
Fixes#5795.
If we happen to read with offset that is after the end of file of a
device, return 0 to indicate EOF. If we return a negative value,
userspace will think that something bad happened when it's really not
the case.
This implements a fallback to munmap that unmaps multiple regions at a
time, with splitting some when needed.
The way it is implemented is possibly not optimal, due to it searching
without looking into the cache
Instead of blindly resetting every AHCI port, let's just reset only the
controller by default. The user can still request to reset everything
with a new kernel boot argument called ahci_reset_mode which is set
by default to "controller", so the code will only invoke an HBA reset.
This kernel boot argument can be set to 3 different values:
1. "controller" - reset the HBA and skip resetting AHCI ports
2. "none" - don't reset anything, so we rely on the firmware to
initialize the AHCI HBA and ports for us.
3. "complete" - reset the AHCI HBA and ports.
Instead of waiting for the AHCI HBA to reset the signature after SATA
reset sequence, let's just check if the Port x Serial ATA Status
register was set to value 3, indicating that device was detected
and phy communication was established.
The intention is to make the boot to be faster, therefore we should
decrease the time deltas in timeout loops to allow earlier break
from these.
Also, there's no need to wait 10 milliseconds before setting
the interface state to "no action request" during the reset sequence.
The system is extremely sensitive to heap allocations during heap
expansion. This was causing frequent OOM panics under various loads.
Work around the issue for now by putting the logging behind
KMALLOC_DEBUG. Ideally dmesgln() & friends would not reqiure any
heap allocations, but we're not there right now.
Fixes#5724.
