Add io_mapping_init_wc() and add a third (unused) parameter to
io_mapping_map_wc().
Reviewed by: hselasky
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11286
memory map request. When the VM fault handler is NULL a return code of
VM_PAGER_BAD is returned from the character device's pager populate
handler. This fixes compatibility with Linux.
MFC after: 1 week
Sponsored by: Mellanox Technologies
list.h includes a number of FreeBSD headers as a workaround for the
LIST_HEAD name collision. To reduce pollution, avoid including list.h
in commonly used headers when it is not explicitly needed.
Reviewed by: hselasky
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D11249
In particular:
- Don't evaluate event conditions with a sleepqueue lock held, since such
code may attempt to acquire arbitrary locks.
- Fix the return value for wait_event_interruptible() in the case that the
wait is interrupted by a signal.
- Implement wait_on_bit_timeout() and wait_on_atomic_t().
- Implement some functions used to test for pending signals.
- Implement a number of wait_event_*() variants and unify the existing
implementations.
- Unify the mechanism used by wait_event_*() and schedule() to put the
calling thread to sleep.
This is required to support updated DRM drivers. Thanks to hselasky for
finding and fixing a number of bugs in the original revision.
Reviewed by: hselasky
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D10986
ARM and MIPS fail universe builds.
ARM and MIPS are missing the following:
* VM_MEMATTR_WRITE_THROUGH
* VM_MEMATTR_WRITE_COMBINING
Pointy-hat to: jhibbits
arm, mips, and powerpc all implement pmap_mapdev_attr() and pmap_unmapdev(),
so add those archs to the checks. powerpc also includes the atomic_swap_*()
functions, so add that to the supported list as well. Not tested except by
compiling powerpc.
Reviewed by: markj
CPU_FOREACH() is not available until SI_SUB_CPU at SI_ORDER_ANY
when the LinuxKPI is loaded as part of the kernel.
MFC after: 1 week
Sponsored by: Mellanox Technologies
kqueue() does not set non-blocking I/O mode for event driven read of
file descriptors. This means the LinuxKPI internal kqueue read and
write event flags must be updated before the next read and/or write
system call. Else the read and/or write system call may block. This
can happen when there is no more data to read following a previous
read event. Then the application also gets blocked from processing
other events. This situation can also be solved by the applications
setting and using non-blocking I/O mode.
MFC after: 1 week
Sponsored by: Mellanox Technologies
character devices. In Linux the FIONBIO IOCTL is handled by the kernel
and not the drivers. Also need return success for the FIOASYNC ioctl
due to existing logic in kern_fcntl() even though it is not supported
currently.
MFC after: 1 week
Sponsored by: Mellanox Technologies
polling contexts in the LinuxKPI.
After the kqueue() support was added to the LinuxKPI in r319409 the
Linux poll file operation will be used outside the system file polling
callback function, which can cause a NULL-pointer panic inside
selrecord() because curthread->td_sel is set to NULL. This patch moves
the selrecord() call away from poll_wait() and to the system file poll
callback function in the LinuxKPI, which essentially wraps the Linux
one. This is similar to what the cuse(3) module is currently doing.
Refer to sys/fs/cuse/*.[ch] for more details.
MFC after: 1 week
Sponsored by: Mellanox Technologies
ioctl(), read() and write() system call handlers. This error code is
internal to the kernel and should not be seen by user-space programs
according to Linux.
Submitted by: Yanko Yankulov <yanko.yankulov@gmail.com>
MFC after: 1 week
Sponsored by: Mellanox Technologies
devices. The implementation allows read and write filters to be
created and piggybacks on the poll() file operation to determine when
a filter should trigger. The piggyback mechanism is simply to check
for the EWOULDBLOCK or EAGAIN return code from read(), write() or
ioctl() system calls and then update the kqueue() polling state bits.
The implementation is similar to the one found in the cuse(3) module.
Refer to sys/fs/cuse/*.[ch] for more details.
MFC after: 1 week
Sponsored by: Mellanox Technologies
printk_ratelimited() in the LinuxKPI.
While at it fix the inclusion guard of printk.h to be similar to the
rest of the LinuxKPI header files.
MFC after: 1 week
Sponsored by: Mellanox Technologies
task structure to avoid deadlock when tearing down the VM object
during a process exit.
Found by: markj @
MFC after: 1 week
Sponsored by: Mellanox Technologies
it shouldn't be called.
Background:
The Linux VM open operation is called when a new VMA is
created on top of the current VMA. This is done through either mremap
flow or split_vma, usually due to mlock, madvise, munmap and so
on. This is currently not supported by the LinuxKPI.
MFC after: 1 week
Sponsored by: Mellanox Technologies
- Allow "struct linux_file" to be refcounted when its "_file" member
is NULL by using its "f_count" field. The reference counts are
transferred to the file structure when the file descriptor is
installed.
- Add missing vdrop() calls for error cases during open().
- Set the "_file" member of "struct linux_file" during open. This
allows use of refcounting through get_file() and fput() with LinuxKPI
character devices.
MFC after: 1 week
Sponsored by: Mellanox Technologies
kern_yield(0) effectively causes the calling thread to be rescheduled
immediately since it resets the thread's priority to the highest possible
value. This can cause livelocks when the pattern
"while (!trylock()) kern_yield(0);" is used since the thread holding the
lock may linger on the runqueue for the CPU on which the looping thread is
running.
MFC after: 1 week
CPU_FOREACH() is not available until SI_SUB_CPU at SI_ORDER_ANY
when the LinuxKPI is loaded as part of the kernel.
MFC after: 1 week
Sponsored by: Mellanox Technologies
Background:
The same VM object might be shared by multiple processes and the
mm_struct is usually freed when a process exits.
Grab a reference on the mm_struct while the vmap is in the
linux_vma_head list in case the first process which inserted a VM
object has exited.
Tested by: kwm @
MFC after: 1 week
Sponsored by: Mellanox Technologies
linux_page_address() function in the LinuxKPI. This solves an issue
where the return value from linux_page_address() is passed to
kmem_free().
MFC after: 1 week
Sponsored by: Mellanox Technologies
kit, CK, in the LinuxKPI.
When threads are pinned to a CPU core or when there is only one CPU,
it can happen that a higher priority thread can call the CK
synchronize function while a lower priority thread holds the read
lock. Because the CK's synchronize is a simple wait loop this can lead
to a deadlock situation. To solve this problem use the recently
introduced CK's wait callback function.
When detecting a CK blocking condition figure out the lowest priority
among the blockers and update the calling thread's priority and
yield. If another CPU core is holding the read lock, pin the thread to
the blocked CPU core and update the priority. The calling threads
priority and CPU bindings are restored before return.
If a thread holding a CK read lock is detected to be sleeping, pause()
will be used instead of yield().
MFC after: 1 week
Sponsored by: Mellanox Technologies
CPUs when allocating a LinuxKPI workqueue. This also ensures that the
created taskqueue always have a non-zero number of worker threads.
MFC after: 1 week
Sponsored by: Mellanox Technologies
