Previously only some of the ID register fields were 64 bit. To allow
for a script to generate these mark them all 64 bit. To allow for their
use in assembly we need to use the UINT64_C macro via a new UL macro
to stop the lines from being too long.
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D20977
we should test ATTR_SW_DBM, not ATTR_AP_RW, to determine whether to set
PGA_WRITEABLE. In effect, we are currently setting PGA_WRITEABLE based on
whether the dirty bit is preset, not whether the mapping is writeable.
Correct this mistake.
Reviewed by: markj
X-MFC with: r350004
Differential Revision: https://reviews.freebsd.org/D21013
where the page table entry was previously invalid. (Note that I did not
replace pmap_load_store() when it was followed by a TLB invalidation, even
if we are not using the return value from pmap_load_store().)
Correct an error in pmap_enter(). A test for determining when to set
PGA_WRITEABLE was always true, even if the mapping was read only.
In pmap_enter_l2(), when replacing an empty kernel page table page by a
superpage mapping, clear the old l2 entry and issue a TLB invalidation. My
reading of the ARM architecture manual leads me to believe that the TLB
could hold an intermediate entry referencing the empty kernel page table
page even though it contains no valid mappings.
Replace a couple direct uses of atomic_clear_64() by the new
pmap_clear_bits().
In a couple comments, replace the term "paging-structure caches", which is
an Intel-specific term for the caches that hold intermediate entries in the
page table, with wording that is more consistent with the ARM architecture
manual.
Reviewed by: markj
X-MFC after: r350004
Differential Revision: https://reviews.freebsd.org/D20998
Add HWCAP support for arm64.
defines are the same as in Linux and a userland program can use
elf_aux_info to get the data.
We only save the common denominator for all cores in case the
big and little cluster have different support (this is known to
exists even if we don't support those SoCs in FreeBSD)
Differential Revision: https://reviews.freebsd.org/D17137
r350004 added most of the machinery needed to support hardware DBM
management, but it did not intend to actually enable use of the hardware
DBM bit.
Reviewed by: andrew
MFC with: r350004
Sponsored by: The FreeBSD Foundation
After r349117 and r349122, some mapping attribute changes do not trigger
superpage demotion. However, pmap_demote_l2() was not updated to ensure
that the replacement L3 entries carry any attribute changes that
occurred since promotion.
Reported and tested by: manu
Reviewed by: alc
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20965
syscallret() doesn't use error anymore. Fix a few other places to permit
removing the return value from syscallenter() entirely.
- Remove a duplicated assertion from arm's syscall().
- Use td_errno for amd64_syscall_ret_flush_l1d.
Reviewed by: kib
MFC after: 1 month
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D2090
Previously the arm64 pmap did no reference or modification tracking;
all mappings were treated as referenced and all read-write mappings
were treated as dirty. This change implements software management
of these attributes.
Dirty bit management is implemented to emulate ARMv8.1's optional
hardware dirty bit modifier management, following a suggestion from alc.
In particular, a mapping with ATTR_SW_DBM set is logically writeable and
is dirty if the ATTR_AP_RW_BIT bit is clear. Mappings with
ATTR_AP_RW_BIT set are write-protected, and a write access will trigger
a permission fault. pmap_fault() handles permission faults for such
mappings and marks the page dirty by clearing ATTR_AP_RW_BIT, thus
mapping the page read-write.
Reviewed by: alc
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20907
TLB entry. Specifically, at the start of pmap_enter_quick_locked(), we
would sometimes have a TLB entry for an invalid PTE, and we would need to
issue a TLB invalidation before exiting pmap_enter_quick_locked(). However,
we should never have a TLB entry for an invalid PTE. r349905 has addressed
the root cause of the problem, and so we no longer need this workaround.
X-MFC after: r349905
Casueword(9) on ll/sc architectures must be prepared for userspace
constantly modifying the same cache line as containing the CAS word,
and not loop infinitely. Otherwise, rogue userspace livelocks the
kernel.
To fix the issue, change casueword(9) interface to return new value 1
indicating that either comparision or store failed, instead of relying
on the oldval == *oldvalp comparison. The primitive no longer retries
the operation if it failed spuriously. Modify callers of
casueword(9), all in kern_umtx.c, to handle retries, and react to
stops and requests to terminate between retries.
On x86, despite cmpxchg should not return spurious failures, we can
take advantage of the new interface and just return PSL.ZF.
Reviewed by: andrew (arm64, previous version), markj
Tested by: pho
Reported by: https://xenbits.xen.org/xsa/advisory-295.txt
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D20772
- Check for ATTR_SW_MANAGED before anything else.
- Use pmap_pte_dirty() in pmap_remove_pages().
No functional change intended.
Reviewed by: alc
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
register values" of the architecture manual, an isb instruction should be
executed after updating ttbr0_el1 and before invalidating the TLB. The
lack of this instruction in pmap_activate() appears to be the reason why
andrew@ and I have observed an unexpected TLB entry for an invalid PTE on
entry to pmap_enter_quick_locked(). Thus, we should now be able to revert
the workaround committed in r349442.
Reviewed by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20904
of pmap_load_clear(), in places where we don't care about the page table
entry's prior contents.
Eliminate an unnecessary pmap_load() from pmap_remove_all(). Instead, use
the value returned by the pmap_load_clear() on the very next line. (In the
future, when we support "hardware dirty bit management", using the value
from the pmap_load() rather than the pmap_load_clear() would have actually
been an error because the dirty bit could potentially change between the
pmap_load() and the pmap_load_clear().)
A KASSERT() in pmap_enter(), which originated in the amd64 pmap, was meant
to check the value returned by the pmap_load_clear() on the previous line.
However, we were ignoring the value returned by the pmap_load_clear(), and
so the KASSERT() was not serving its intended purpose. Use the value
returned by the pmap_load_clear() in the KASSERT().
MFC after: 2 weeks
The hold_count and wire_count fields of struct vm_page are separate
reference counters with similar semantics. The remaining essential
differences are that holds are not counted as a reference with respect
to LRU, and holds have an implicit free-on-last unhold semantic whereas
vm_page_unwire() callers must explicitly determine whether to free the
page once the last reference to the page is released.
This change removes the KPIs which directly manipulate hold_count.
Functions such as vm_fault_quick_hold_pages() now return wired pages
instead. Since r328977 the overhead of maintaining LRU for wired pages
is lower, and in many cases vm_fault_quick_hold_pages() callers would
swap holds for wirings on the returned pages anyway, so with this change
we remove a number of page lock acquisitions.
No functional change is intended. __FreeBSD_version is bumped.
Reviewed by: alc, kib
Discussed with: jeff
Discussed with: jhb, np (cxgbe)
Tested by: pho (previous version)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19247
1. Use _pmap_alloc_l3() instead of pmap_alloc_l3() in order to handle the
possibility that a superpage mapping for "va" was created while we slept.
(This is derived from the amd64 version.)
2. Eliminate code for allocating kernel page table pages. Kernel page
table pages are preallocated by pmap_growkernel().
3. Eliminate duplicated unlock operations when KERN_RESOURCE_SHORTAGE is
returned.
MFC after: 2 weeks
restructure cache_handle_range so that all of the data cache operations are
performed before any instruction cache operations. Then, we only need one
barrier between the data and instruction cache operations and one barrier
after the instruction cache operations.
On an Amazon EC2 a1.2xlarge instance, this simple change reduces the time
for a "make -j8 buildworld" by 9%.
Reviewed by: andrew
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20848
copy the VFP registers.
arvm7 VFP uses 32 64bits fp registers (but those could be used in pairs to
make 16 128bits registers), while aarch64 uses 32 128bits fp registers, so
we have to copy the value of each register.
that replaced a pmap_invalidate_page() with a dsb(ishst) in
pmap_enter_quick_locked(). Even though this change is in principle
correct, I am seeing occasional, spurious bus errors that are only
reproducible without this pmap_invalidate_page(). (None of adding an
isb, "upgrading" the dsb to wait on loads as well as stores, or
disabling superpage mappings eliminates the bus errors.) Add an XXX
comment explaining why the pmap_invalidate_page() is being performed.
Discussed with: andrew, markj
In set_regs32()/fill_regs32(), we have to get/set SP and LR from/to
tf_x[13] and tf_x[14].
set_regs() and fill_regs() may be called for a 32bits process, if the process
is ptrace'd from a 64bits debugger. So, in set_regs() and fill_regs(), get
or set PC and SPSR from where the debugger expects it, from tf_x[15] and
tf_x[16].
Print warnings for some bad kernel configurations (like NUMA disabled
with multiple domains). Check and report some firmware errors (like
incorrect proximity domain entries).
Differential Revision: https://reviews.freebsd.org/D20416
We now support multiple ITS blocks raising interrupts to a CPU.
Add all available CPUs to the ITS when no NUMA information is
available.
This reverts the check added in r340602, at that tim we did not
suppport multiple ITS blocks for a CPU.
Differential Revision: https://reviews.freebsd.org/D20417
Now that GICV3_IVAR_REDIST is available, GICV3_IVAR_REDIST_VADDR
is unused and can be removed. Drop the define and add a comment.
Reviewed by: andrew
Differential Revision: https://reviews.freebsd.org/D20454
perform a TLB invalidation. A barrier suffices. (See r343876.)
Add a comment to pmap_enter_quick_locked() in order to highlight the
fact that it does not replace valid mappings.
Correct a typo in one of pmap_enter()'s comments.
MFC after: 1 week
(1) pmap_remove(), where it eliminates redundant TLB invalidations by
pmap_remove() and pmap_remove_l3(), and (2) pmap_enter_l2(), where it may
optimize the TLB invalidations by batching them.
Reviewed by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D12725
Implement wiring changes on superpage mappings. Previously, a superpage
mapping was unconditionally demoted by pmap_unwire(), even if the wiring
change applied to the entire superpage mapping.
Rewrite a comment to use the arm64 names for bits in a page table entry.
Previously, the bits were referred to by their x86 names.
Use atomic_"op"_64() instead of atomic_"op"_long() to update a page table
entry in order to match the prevailing style in this file.
MFC after: 10 days
Implement protection changes on superpage mappings. Previously, a superpage
mapping was unconditionally demoted by pmap_protect(), even if the
protection change applied to the entire superpage mapping.
Precompute the bit mask describing the protection changes rather than
recomputing it for every page table entry that is changed.
Skip page table entries that already have the requested protection changes
in place.
Reviewed by: andrew, kib
MFC after: 10 days
Differential Revision: https://reviews.freebsd.org/D20657
it only called vm_page_dirty() on the first of the superpage's constituent
4KB pages. This revision corrects that error, calling vm_page_dirty() on
all of superpage's constituent 4KB pages.
MFC after: 3 days
I just happenned to have 3rd party code using 'var' as the output variable
which drew my attention to this. variables defined inside macros should be
prefixed to avoid getting shadowed varable wanrings from clang.
not performed directly by the pmap. Instead, they are performed by
vm_page_free_pages_toq(). (This is the same approach that we use on x86.)
Reviewed by: kib, markj
MFC after: 10 days
Differential Revision: https://reviews.freebsd.org/D20627
demotion failure. Otherwise, some callers to pmap_demote_l2_locked(), such
as pmap_protect(), may leave an incorrect mapping in place on a demotion
failure.
Change pmap_demote_l2_locked() so that it handles addresses that are not
superpage aligned. Some callers to pmap_demote_l2_locked(), such as
pmap_protect(), may not pass a superpage aligned address.
Change pmap_enter_l2() so that it correctly calls vm_page_free_pages_toq().
The arm64 pmap is updating the count of wired pages when freeing page table
pages, so pmap_enter_l2() should pass false to vm_page_free_pages_toq().
Optimize TLB invalidation in pmap_remove_l2().
Reviewed by: kib, markj (an earlier version)
Discussed with: andrew
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D20585
Hide unused code under #ifdef notyet (in one case the only caller is under
that same ifdef), or if it is arm (not arm64) specific code under the
__arm__ ifdef to not yield -Wunused-function warnings during the arm64
kernel compile.
MFC after: 2 weeks
The A3700 has a different GPIO controller and thus, do not use the old (and
shared) code for Marvell.
The pinctrl driver, also part of the controller, is not supported yet (but
the implementation should be straightforward).
Sponsored by: Rubicon Communications, LLC (Netgate)
previously addressed in r348246.
This pmap problem also exists on arm64 and riscv. However, the original
solution developed for amd64 and i386 cannot be used on arm64 and riscv. In
particular, arm64 and riscv do not define a PG_PROMOTED flag in their level
2 PTEs. (A PG_PROMOTED flag makes no sense on arm64, where unlike x86 or
riscv we are required to break the old 4KB mappings before making the 2MB
mapping; and on riscv there are no unused bits in the PTE to define a
PG_PROMOTED flag.)
This commit implements an alternative solution that can be used on all four
architectures. Moreover, this solution has two other advantages. First, on
older AMD processors that required the Erratum 383 workaround, it is less
costly. Specifically, it avoids unnecessary calls to pmap_fill_ptp() on a
superpage demotion. Second, it enables the elimination of some calls to
pagezero() in pmap_kernel_remove_{l2,pde}().
In addition, remove a related stale comment from pmap_enter_{l2,pde}().
Reviewed by: kib, markj (an earlier version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20538
syscalls.conf is included using "." which per the Open Group:
If file does not contain a <slash>, the shell shall use the search
path specified by PATH to find the directory containing file.
POSIX shells don't fall back to the current working directory.
Submitted by: Nathaniel Wesley Filardo <nwf20@cl.cam.ac.uk>
Reviewed by: bdrewery
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D20476