the memory or D-cache, depending on the semantics of the platform.
vm_sync_icache() is basically a wrapper around pmap_sync_icache(),
that translates the vm_map_t argumument to pmap_t.
o Introduce pmap_sync_icache() to all PMAP implementation. For powerpc
it replaces the pmap_page_executable() function, added to solve
the I-cache problem in uiomove_fromphys().
o In proc_rwmem() call vm_sync_icache() when writing to a page that
has execute permissions. This assures that when breakpoints are
written, the I-cache will be coherent and the process will actually
hit the breakpoint.
o This also fixes the Book-E PMAP implementation that was missing
necessary locking while trying to deal with the I-cache coherency
in pmap_enter() (read: mmu_booke_enter_locked).
The key property of this change is that the I-cache is made coherent
*after* writes have been done. Doing it in the PMAP layer when adding
or changing a mapping means that the I-cache is made coherent *before*
any writes happen. The difference is key when the I-cache prefetches.
dependent memory attributes:
Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the
fact that there are machine-dependent memory attributes that have
nothing to do with controlling the cache's behavior.
Introduce vm_object_set_memattr() for setting the default memory
attributes that will be given to an object's pages.
Introduce and use pmap_page_{get,set}_memattr() for getting and
setting a page's machine-dependent memory attributes. Add full
support for these functions on amd64 and i386 and stubs for them on
the other architectures. The function pmap_page_set_memattr() is also
responsible for any other machine-dependent aspects of changing a
page's memory attributes, such as flushing the cache or updating the
direct map. The uses include kmem_alloc_contig(), vm_page_alloc(),
and the device pager:
kmem_alloc_contig() can now be used to allocate kernel memory with
non-default memory attributes on amd64 and i386.
vm_page_alloc() and the device pager will set the memory attributes
for the real or fictitious page according to the object's default
memory attributes.
Update the various pmap functions on amd64 and i386 that map pages to
incorporate each page's memory attributes in the mapping.
Notes: (1) Inherent to this design are safety features that prevent
the specification of inconsistent memory attributes by different
mappings on amd64 and i386. In addition, the device pager provides a
warning when a device driver creates a fictitious page with memory
attributes that are inconsistent with the real page that the
fictitious page is an alias for. (2) Storing the machine-dependent
memory attributes for amd64 and i386 as a dedicated "int" in "struct
md_page" represents a compromise between space efficiency and the ease
of MFCing these changes to RELENG_7.
In collaboration with: jhb
Approved by: re (kib)
new platform module. These are probed in early boot, and have the
responsibility of determining the layout of physical memory, determining
the CPU timebase frequency, and handling the zoo of SMP mechanisms
found on PowerPC.
Reviewed by: marcel, raj
Book-E parts by: raj
on a generic dumper that creates an ELF core file and
uses PMAP functions to scan and iterate over memory
chunks, as well as handle memory mappings used during
dumping.
the PMAP layer can choose to return physical memory
chunks or virtual memory chunks. For minidumps, the
chunks should be virtual.
The default MMU I/F implementation for the scan_md()
method returns NULL. Thus, when a PMAP implementation
does not implement the required methods, an empty
core file is created. Here, empty means having an ELF
header only.
Obtained from: Juniper Networks
o Eliminate tlb0[] (a s/w copy of TLB0)
- The table contents cannot be maintained reliably in multiple MMU
environments, where asynchronous events (invalidations from other cores)
can change our local TLB0 contents underneath.
- Simplify and optimize TLB flushing: system wide invalidations are
performed using tlbivax instruction (propagates to other cores), for
local MMU invalidations a new optimized routine (assembly) is introduced.
o Improve and simplify TID allocation and management.
- Let each core keep track of its TID allocations.
- Simplify TID recycling, eliminate dead code.
- Drop the now unused powerpc/booke/support.S file.
o Improve page tables management logic.
o Simplify TLB1 manipulation routines.
o Other improvements and polishing.
Obtained from: Freescale, Semihalf
was written into a user's address space. The fix is to modify uiomove_fromphys
to sync the icache when an executable user-space page is written into.
Alan Cox suggested that there should probably be a higher-level interface
to this in the ptrace code, but agreed that this is an OK short-term solution.
Files changed:
pmap.h - declaration of pmap_page_executable()
pmap_dispatch.c - pass through the page_executable call to the mmu object
mmu_oea.c - implement the page_executable method by examining the PTE_EXEC
field in the vm_page_t
uio_machdep.c - in uiomove_fromphys(), if the op was a UIO_WRITE to user-space,
and if the page is executable, sync the icache since this is at the least
a breakpoint-write from gdb.
Reported by: marcel
Tested by: marcel, grehan on g3+g4
Discussed with: alc
MFC after: 2 weeks
- Move vtophys() macros next to vtopte() where vtopte() exists to match
comments above vtopte().
- Remove references to the alternate address space in the comment above
vtopte(). amd64 never had the alternate address space, and i386 lost it
prior to PAE support being added.
- s/entires/entries/ in comments.
Reviewed by: alc
the interface. This allows run-time selection of MMU code, based
on CPU-type detection, or tunable-overrides when testing new code.
Pre-requisite for G5 support.
conf/files.powerpc
- remove pmap.c
- add mmu_if.h, mmu_oea.c, pmap_dispatch.c
powerpc/include/mmuvar.h
- definitions for MMU implementations
powerpc/include/pmap.h
- remove pmap_pte_spill declaration
- add pmap_mmu_install declaration
- size the phys_avail array
- pmap_bootstrapped is now global-scope
powerpc/powerpc/machdep.c
- call kobj_machdep_init early in the boot sequence to allow
kobj usage prior to SI_SUB_LOCK
- install the OEA pmap code. This will be moved to CPU-specific
init code in the future.
powerpc/powerpc/mmu_if.m
- Kobj MMU interface definitions
powerpc/powerpc/pmap_dispatch.c
- central dispatch for pmap calls
- contains the global mmu kobj and the routine to locate the
the mmu implementation and init the kobj
- culled long-dead #define's
- segment register defs moved to sr.h
- NPMAPS moved to pmap.h
- KERNBASE moved to vmparam.h
- removed include of <machine/cpu.h> and fixed src files that
relied on this.
Modifying segment register code no longer causes gcc rebuilds :-)
are machine dependent because they are not required to update the tlb when
mappings are added or removed, and doing so is machine dependent.
In addition, an implementation may require that pages mapped with pmap_kenter
have a backing vm_page_t, which is not necessarily true of all physical
pages, and so may choose to pass the vm_page_t to pmap_kenter instead of the
physical address in order to make this requirement clear.
i386/ia64/alpha - catch up to sparc64/ppc:
- replace pmap_kernel() with refs to kernel_pmap
- change kernel_pmap pointer to (&kernel_pmap_store)
(this is a speedup since ld can set these at compile/link time)
all platforms (as suggested by jake):
- gc unused pmap_reference
- gc unused pmap_destroy
- gc unused struct pmap.pm_count
(we never used pm_count - we track address space sharing at the vmspace)
boot sequence.
The new pmap.c is based on NetBSD's newer pmap.c (for the mpc6xx processors)
which is 70% faster than the older code that the original pmap.c was based
on. It has also been based on the framework established by jake's initial
sparc64 pmap.c.
There is no change to how far the kernel gets (it makes it to the mountroot
prompt in psim) but the new pmap code is a lot cleaner.
Obtained from: NetBSD (pmap code)
