Commit Graph

58 Commits

Author SHA1 Message Date
Rick Edgecombe
bf6f3c1840 csky: use initializer for struct vm_unmapped_area_info
Future changes will need to add a new member to struct
vm_unmapped_area_info.  This would cause trouble for any call site that
doesn't initialize the struct.  Currently every caller sets each member
manually, so if new members are added they will be uninitialized and the
core code parsing the struct will see garbage in the new member.

It could be possible to initialize the new member manually to 0 at each
call site.  This and a couple other options were discussed, and a working
consensus (see links) was that in general the best way to accomplish this
would be via static initialization with designated member initiators. 
Having some struct vm_unmapped_area_info instances not zero initialized
will put those sites at risk of feeding garbage into vm_unmapped_area() if
the convention is to zero initialize the struct and any new member
addition misses a call site that initializes each member manually.

It could be possible to leave the code mostly untouched, and just change
the line:
struct vm_unmapped_area_info info
to:
struct vm_unmapped_area_info info = {};

However, that would leave cleanup for the members that are manually set to
zero, as it would no longer be required.

So to be reduce the chance of bugs via uninitialized members, instead
simply continue the process to initialize the struct this way tree wide. 
This will zero any unspecified members.  Move the member initializers to
the struct declaration when they are known at that time.  Leave the
members out that were manually initialized to zero, as this would be
redundant for designated initializers.

Link: https://lkml.kernel.org/r/20240326021656.202649-8-rick.p.edgecombe@intel.com
Link: https://lore.kernel.org/lkml/202402280912.33AEE7A9CF@keescook/#t
Link: https://lore.kernel.org/lkml/j7bfvig3gew3qruouxrh7z7ehjjafrgkbcmg6tcghhfh3rhmzi@wzlcoecgy5rs/
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Guo Ren <guoren@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Helge Deller <deller@gmx.de>
Cc: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:56:27 -07:00
Alexandre Ghiti
7a92fc8b4d mm: Introduce flush_cache_vmap_early()
The pcpu setup when using the page allocator sets up a new vmalloc
mapping very early in the boot process, so early that it cannot use the
flush_cache_vmap() function which may depend on structures not yet
initialized (for example in riscv, we currently send an IPI to flush
other cpus TLB).

But on some architectures, we must call flush_cache_vmap(): for example,
in riscv, some uarchs can cache invalid TLB entries so we need to flush
the new established mapping to avoid taking an exception.

So fix this by introducing a new function flush_cache_vmap_early() which
is called right after setting the new page table entry and before
accessing this new mapping. This new function implements a local flush
tlb on riscv and is no-op for other architectures (same as today).

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dennis Zhou <dennis@kernel.org>
2023-12-14 00:23:17 -08:00
Joel Granados
8f06eef7b8 c-sky: Remove now superfluous sentinel element from ctl_talbe array
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

Remove sentinel from alignment_tbl ctl_table array. This removal is safe
because register_sysctl_init implicitly uses ARRAY_SIZE() in addition to
checking for the sentinel.

Acked-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-10-10 15:22:02 -07:00
Matthew Wilcox (Oracle)
203b7b6aad mm: rationalise flush_icache_pages() and flush_icache_page()
Move the default (no-op) implementation of flush_icache_pages() to
<linux/cacheflush.h> from <asm-generic/cacheflush.h>.  Remove the
flush_icache_page() wrapper from each architecture into
<linux/cacheflush.h>.

Link: https://lkml.kernel.org/r/20230802151406.3735276-32-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24 16:20:25 -07:00
Matthew Wilcox (Oracle)
e724e7aaf9 csky: implement the new page table range API
Add PFN_PTE_SHIFT, update_mmu_cache_range() and flush_dcache_folio().
Change the PG_dcache_clean flag from being per-page to per-folio.

Link: https://lkml.kernel.org/r/20230802151406.3735276-12-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24 16:20:20 -07:00
Linus Torvalds
a1f749de8a arch/csky patches for 6.4
The pull request we've done:
  - Remove CPU_TLB_SIZE config
  - Prevent spurious page faults
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Merge tag 'csky-for-linus-6.4' of https://github.com/c-sky/csky-linux

Pull arch/csky updates from Guo Ren:

 - Remove CPU_TLB_SIZE config

 - Prevent spurious page faults

* tag 'csky-for-linus-6.4' of https://github.com/c-sky/csky-linux:
  csky: mmu: Prevent spurious page faults
  csky: remove obsolete config CPU_TLB_SIZE
2023-05-04 12:25:05 -07:00
Luis Chamberlain
adf11ea872 csky: simplify alignment sysctl registration
Using register_sysctl_paths() is only required if we are using
leafs with entries but all we are doing is creates leafs with
just one leaf and then entries and register_sysctl_init() works
well with that already.

The 555 permission is already retained by the new_dir() proc
sysctl directory creator.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-13 11:49:20 -07:00
Guo Ren
1f62ed00a5 csky: mmu: Prevent spurious page faults
C-SKY MMU would pre-fetch invalid pte entries, and it could work with
flush_tlb_fix_spurious_fault, but the additional page fault exceptions
would reduce performance. So flushing the entry of the TLB would prevent
the following spurious page faults. Here is the test code:

define DATA_LEN  4096
define COPY_NUM  (504*100)

unsigned char src[DATA_LEN*COPY_NUM] = {0};
unsigned char dst[DATA_LEN*COPY_NUM] = {0};

unsigned char func_src[DATA_LEN*COPY_NUM] = {0};
unsigned char func_dst[DATA_LEN*COPY_NUM] = {0};

void main(void)
{
	int j;
	for (j = 0; j < COPY_NUM; j++)
		memcpy(&dst[j*DATA_LEN], &src[j*DATA_LEN], 4);
}

perf stat -e page-faults ./main.elf

The amount of page fault traps would be reduced in half with the patch.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
2023-04-13 02:36:14 -04:00
David Hildenbrand
41e0d49104 csky/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE
Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the
offset.  This reduces the maximum swap space per file to 16 GiB (was 32
GiB).

We might actually be able to reuse one of the other software bits
(_PAGE_READ / PAGE_WRITE) instead, because we only have to keep
pte_present(), pte_none() and HW happy.  For now, let's keep it simple
because there might be something non-obvious.

Link: https://lkml.kernel.org/r/20230113171026.582290-6-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02 22:33:06 -08:00
Guo Ren
45fef4c4b9 csky: abiv1: Fixup compile error
LD      vmlinux.o
arch/csky/lib/string.o: In function `memmove':
string.c:(.text+0x108): multiple definition of `memmove'
lib/string.o:string.c:(.text+0x7e8): first defined here
arch/csky/lib/string.o: In function `memset':
string.c:(.text+0x148): multiple definition of `memset'
lib/string.o:string.c:(.text+0x2ac): first defined here
scripts/Makefile.vmlinux_o:68: recipe for target 'vmlinux.o' failed
make[4]: *** [vmlinux.o] Error 1

Fixes: e4df2d5e85 ("csky: Add C based string functions")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Cc: <stable@vger.kernel.org>
2022-07-31 22:39:23 -04:00
Matteo Croce
e4df2d5e85 csky: Add C based string functions
Try to access RAM with the largest bit width possible, but without
doing unaligned accesses.

A further improvement could be to use multiple read and writes as the
assembly version was trying to do.

Tested on a BeagleV Starlight with a SiFive U74 core, where the
improvement is noticeable.

Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Co-developed-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2022-04-18 21:23:55 +08:00
Nathan Chancellor
751971af2e csky: Fix function name in csky_alignment() and die()
When building ARCH=csky defconfig:

arch/csky/kernel/traps.c: In function 'die':
arch/csky/kernel/traps.c:112:17: error: implicit declaration of function
'make_dead_task' [-Werror=implicit-function-declaration]
  112 |                 make_dead_task(SIGSEGV);
      |                 ^~~~~~~~~~~~~~

The function's name is make_task_dead(), change it so there is no more
build error.

Fixes: 0e25498f8c ("exit: Add and use make_task_dead.")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lkml.kernel.org/r/20211227184851.2297759-4-nathan@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2022-01-08 09:43:03 -06:00
Eric W. Biederman
0e25498f8c exit: Add and use make_task_dead.
There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-13 12:04:45 -06:00
Christoph Hellwig
f358afc52c mm: remove flush_kernel_dcache_page
flush_kernel_dcache_page is a rather confusing interface that implements a
subset of flush_dcache_page by not being able to properly handle page
cache mapped pages.

The only callers left are in the exec code as all other previous callers
were incorrect as they could have dealt with page cache pages.  Replace
the calls to flush_kernel_dcache_page with calls to flush_dcache_page,
which for all architectures does either exactly the same thing, can
contains one or more of the following:

 1) an optimization to defer the cache flush for page cache pages not
    mapped into userspace
 2) additional flushing for mapped page cache pages if cache aliases
    are possible

Link: https://lkml.kernel.org/r/20210712060928.4161649-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Matthew Wilcox (Oracle)
842ca547f7 mm: move page_mapping_file to pagemap.h
page_mapping_file() is only used by some architectures, and then it
is usually only used in one place.  Make it a static inline function
so other architectures don't have to carry this dead code.

Link: https://lkml.kernel.org/r/20210317123011.350118-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:37 -07:00
Guo Ren
6607aa6f6b csky: Fixup compile error
: error: C++ style comments are not allowed in ISO C90
 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
 ^
error: (this will be reported only once per input file)

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2021-02-27 22:04:14 +08:00
Guo Ren
0d3b051adb csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO
It could help to reduce the latency of the time-related functions
in user space.

We have referenced arm's and riscv's implementation for the patch.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Vincent Chen <vincent.chen@sifive.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2021-02-27 16:35:09 +08:00
Guo Ren
af94002bda csky: Fixup swapon
Current csky's swappon is broken by wrong swap PTE entry format.
Now redesign the new format for abiv1 & abiv2 and make swappon +
zram work properly on csky machines.

C-SKY PTE has VALID, DIRTY to emulate PRESENT, READ, WRITE, EXEC
attributes. GLOBAL bit is shared by two pages in the same tlb
entry. So we need to keep GLOBAL, VALID, PRESENT zero in swp_pte.

To distinguish PAGE_NONE and swp_pte, we need to use an additional
bit (abiv1 is _PAGE_READ, abiv2 is _PAGE_WRITE).

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2021-02-27 16:32:54 +08:00
Guo Ren
a8fac05acf csky: pgtable.h: Coding convention
C-SKY page table attributes only have 'Dirty' and 'Valid' to
emulate 'PRESENT, READ, WRITE, EXEC, DIRTY, ACCESSED'.

This patch cleanup unnecessary definition.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2021-02-27 16:22:42 +08:00
Guo Ren
87f3248cdb csky: Reconstruct VDSO framework
Reconstruct vdso framework to support future vsyscall,
vgettimeofday features. These are very important features to reduce
system calls into the kernel for performance improvement.

The patch is reference RISC-V's

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-12 09:52:41 +08:00
Guo Ren
3b756ccddb csky: Fix TLB maintenance synchronization problem
TLB invalidate didn't contain a barrier operation in csky cpu and
we need to prevent previous PTW response after TLB invalidation
instruction. Of cause, the ASID changing also needs to take care
of the issue.

CPU0                    CPU1
===============         ===============
set_pte
sync_is()        ->     See the previous set_pte for all harts
tlbi.vas         ->     Invalidate all harts TLB entry & flush pipeline

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2021-01-12 09:52:41 +08:00
Guo Ren
0c8a32eed1 csky: Add memory layout 2.5G(user):1.5G(kernel)
There are two ways for translating va to pa for csky:
 - Use TLB(Translate Lookup Buffer) and PTW (Page Table Walk)
 - Use SSEG0/1 (Simple Segment Mapping)

We use tlb mapping 0-2G and 3G-4G virtual address area and SSEG0/1
are for 2G-2.5G and 2.5G-3G translation. We could disable SSEG0
to use 2G-2.5G as TLB user mapping.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2021-01-12 09:52:40 +08:00
Guo Ren
20f69538b9 csky: Coding convention in entry.S
There is no fixup or feature in the patch, we only cleanup with:

 - Remove unnecessary reg used (r11, r12), just use r9 & r10 &
   syscallid regs as temp useage.
 - Add _TIF_SYSCALL_WORK and _TIF_WORK_MASK to gather macros.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-28 00:18:36 +00:00
Guo Ren
900897591b csky: Fixup CONFIG_PREEMPT panic
log:
[    0.13373200] Calibrating delay loop...
[    0.14077600] ------------[ cut here ]------------
[    0.14116700] WARNING: CPU: 0 PID: 0 at kernel/sched/core.c:3790 preempt_count_add+0xc8/0x11c
[    0.14348000] DEBUG_LOCKS_WARN_ON((preempt_count() < 0))Modules linked in:
[    0.14395100] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0 #7
[    0.14410800]
[    0.14427400] Call Trace:
[    0.14450700] [<807cd226>] dump_stack+0x8a/0xe4
[    0.14473500] [<80072792>] __warn+0x10e/0x15c
[    0.14495900] [<80072852>] warn_slowpath_fmt+0x72/0xc0
[    0.14518600] [<800a5240>] preempt_count_add+0xc8/0x11c
[    0.14544900] [<807ef918>] _raw_spin_lock+0x28/0x68
[    0.14572600] [<800e0eb8>] vprintk_emit+0x84/0x2d8
[    0.14599000] [<800e113a>] vprintk_default+0x2e/0x44
[    0.14625100] [<800e2042>] vprintk_func+0x12a/0x1d0
[    0.14651300] [<800e1804>] printk+0x30/0x48
[    0.14677600] [<80008052>] lockdep_init+0x12/0xb0
[    0.14703800] [<80002080>] start_kernel+0x558/0x7f8
[    0.14730000] [<800052bc>] csky_start+0x58/0x94
[    0.14756600] irq event stamp: 34
[    0.14775100] hardirqs last  enabled at (33): [<80067370>] ret_from_exception+0x2c/0x72
[    0.14793700] hardirqs last disabled at (34): [<800e0eae>] vprintk_emit+0x7a/0x2d8
[    0.14812300] softirqs last  enabled at (32): [<800655b0>] __do_softirq+0x578/0x6d8
[    0.14830800] softirqs last disabled at (25): [<8007b3b8>] irq_exit+0xec/0x128

The preempt_count of reg could be destroyed after csky_do_IRQ without reload
from memory.

After reference to other architectures (arm64, riscv), we move preempt entry
into ret_from_exception and disable irq at the beginning of
ret_from_exception instead of RESTORE_ALL.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reported-by: Lu Baoquan <lu.baoquan@intellif.com>
2020-05-28 00:18:36 +00:00
Liu Yibin
165f2d2858 csky: Fixup msa highest 3 bits mask
Just as comment mentioned, the msa format:

 cr<30/31, 15> MSA register format:
 31 - 29 | 28 - 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
   BA     Reserved  SH  WA  B   SO SEC  C   D   V

So we should shift 29 bits not 28 bits for mask

Signed-off-by: Liu Yibin <jiulong@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-05-13 17:55:05 +08:00
Guo Ren
aefd9461d3 csky: Fixup cpu speculative execution to IO area
For the memory size ( > 512MB, < 1GB), the MSA setting is:

 - SSEG0: PHY_START        , PHY_START + 512MB
 - SSEG1: PHY_START + 512MB, PHY_START + 1GB

But the real memory is no more than 1GB, there is a gap between the
end size of memory and border of 1GB. CPU could speculatively
execute to that gap and if the gap of the bus couldn't respond to
the CPU request, then the crash will happen.

Now make the setting with:

 - SSEG0: PHY_START        , PHY_START + 512MB (no change)
 - SSEG1: Disabled (We use highmem to use the memory of 512MB~1GB)

We also deprecated zhole_szie[] settings, it's only used by arm
style CPUs. All memory gap should use Reserved setting of dts in
csky system.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-04-03 12:40:07 +08:00
Guo Ren
997153b9a7 csky: Add flush_icache_mm to defer flush icache all
Some CPUs don't support icache.va instruction to maintain the whole
smp cores' icache. Using icache.all + IPI casue a lot on performace
and using defer mechanism could reduce the number of calling icache
_flush_all functions.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren
a117673413 csky: Remove unnecessary flush_icache_* implementation
The abiv2 CPUs are all PIPT cache, so there is no need to implement
flush_icache_page function.

The function flush_icache_user_range hasn't been used, so just
remove it.

The function flush_cache_range is not necessary for PIPT cache when
tlb mapping changed.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren
f8e17c17b8 csky: Set regs->usp to kernel sp, when the exception is from kernel
In the past, we didn't care about kernel sp when saving pt_reg. But in some
cases, we still need pt_reg->usp to represent the kernel stack before enter
exception.

For cmpxhg in atomic.S, we need save and restore usp for above.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00
Guo Ren
4ad35c1f56 csky: Fixup 610 vipt cache flush mechanism
610 has vipt aliasing issue, so we need to finish the cache flush
apis mentioned in cachetlb.rst to avoid data corruption.

Here is the list of modified apis in the patch:

 - flush_kernel_dcache_page      (new add)
 - flush_dcache_mmap_lock        (new add)
 - flush_dcache_mmap_unlock      (new add)
 - flush_kernel_vmap_range       (new add)
 - invalidate_kernel_vmap_range  (new add)
 - flush_anon_page               (new add)
 - flush_cache_range             (new add)
 - flush_cache_vmap              (flush all)
 - flush_cache_vunmap            (flush all)
 - flush_cache_mm                (only dcache flush)
 - flush_icache_page             (just nop)
 - copy_from_user_page           (remove no need flush)
 - copy_to_user_page             (remove no need flush)

Change to V2:
 - Fixup compile error with xa_lock*(&mapping->i_pages)

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
2019-08-22 10:44:24 +08:00
Guo Ren
c7e6f0e992 csky: Support kernel non-aligned access
We prohibit non-aligned access in kernel mode, but some special NIC
driver needs to support kernel-state unaligned access. For example,
when the bus does not support unaligned access, IP header parsing
will cause non-aligned access and driver does not recopy the skb
buffer to dma for performance reasons.

Added kernel_enable & user_enable to control unaligned access and
added kernel_count  & user_count for statistical unaligned access.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-08-20 20:15:44 +08:00
Guo Ren
dc140045c0 csky: Fixup defer cache flush for 610
We use defer cache flush mechanism to improve the performance of
610, but the implementation is wrong. We fix it up now and update
the mechanism:

 - Zero page needn't be flushed.
 - If page is file mapping & non-touched in user space, defer flush.
 - If page is anon mapping or dirty file mapping, flush immediately.
 - In update_mmu_cache finish the defer flush by flush_dcache_page().

For 610 we need take care the dcache aliasing issue:
 - VIPT cache with 8K-bytes size per way in 4K page granularity.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-08-20 20:09:14 +08:00
Guo Ren
be819aa6f1 csky: Fixup arch_get_unmapped_area() implementation
Current arch_get_unmapped_area() of abiv1 doesn't use standard kernel
api. After referring to the implementation of arch/arm, we implement
it with vm_unmapped_area() from linux/mm.h.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-08-20 16:09:37 +08:00
Linus Torvalds
a84d2d2906 arch/csky patches for 5.3-rc1
This round of csky subsystem gives two features (ASID algorithm update,
 Perf pmu record support) and some fixups.
 
 Feature:
  - csky: Revert mmu ASID mechanism
  - csky: Add new asid lib code from arm
  - csky: Use generic asid algorithm to implement switch_mm
  - csky: Improve tlb operation with help of asid
 
  - csky: Init pmu as a device
  - csky: Add count-width property for csky pmu
  - csky: Add pmu interrupt support
  - csky: Fix perf record in kernel/user space
  - dt-bindings: csky: Add csky PMU bindings
 
 Fixup:
  - csky: Fixup no panic in kernel for some traps
  - csky: Fixup some error count in 810 & 860.
  - csky: Fixup abiv1 memset error
 
 CI-Tested: https://gitlab.com/c-sky/buildroot/pipelines/68656845
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Merge tag 'csky-for-linus-5.3-rc1' of git://github.com/c-sky/csky-linux

Pull arch/csky pupdates from Guo Ren:
 "This round of csky subsystem gives two features (ASID algorithm
  update, Perf pmu record support) and some fixups.

  ASID updates:
   - Revert mmu ASID mechanism
   - Add new asid lib code from arm
   - Use generic asid algorithm to implement switch_mm
   - Improve tlb operation with help of asid

  Perf pmu record support:
   - Init pmu as a device
   - Add count-width property for csky pmu
   - Add pmu interrupt support
   - Fix perf record in kernel/user space
   - dt-bindings: Add csky PMU bindings

  Fixes:
   - Fixup no panic in kernel for some traps
   - Fixup some error count in 810 & 860.
   - Fixup abiv1 memset error"

* tag 'csky-for-linus-5.3-rc1' of git://github.com/c-sky/csky-linux:
  csky: Fixup abiv1 memset error
  csky: Improve tlb operation with help of asid
  csky: Use generic asid algorithm to implement switch_mm
  csky: Add new asid lib code from arm
  csky: Revert mmu ASID mechanism
  dt-bindings: csky: Add csky PMU bindings
  dt-bindings: interrupt-controller: Update csky mpintc
  csky: Fixup some error count in 810 & 860.
  csky: Fix perf record in kernel/user space
  csky: Add pmu interrupt support
  csky: Add count-width property for csky pmu
  csky: Init pmu as a device
  csky: Fixup no panic in kernel for some traps
  csky: Select intc & timer drivers
2019-07-19 12:15:33 -07:00
Guo Ren
bdfeb0ccea csky: Fixup abiv1 memset error
Current memset implementation in abiv1 is wrong and it'll cause unalign
access. Just remove it and use the generic one. This patch will cause
performance degradation and we will improve it with a new design in next
patchset.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-07-19 14:21:36 +08:00
Guo Ren
22d55f02b8 csky: Use generic asid algorithm to implement switch_mm
Use linux generic asid/vmid algorithm to implement csky
switch_mm function. The algorithm is from arm and it could
work with SMP system. It'll help reduce tlb flush for
switch_mm in task/vm switch.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-07-19 14:21:36 +08:00
Linus Torvalds
5ad18b2e60 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...
2019-07-08 21:48:15 -07:00
Eric W. Biederman
2e1661d267 signal: Remove the task parameter from force_sig_fault
As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.

The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.

The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:

force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29 09:31:43 -05:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Guo Ren
683fafebf9 csky: Use va_pa_offset instead of phys_offset
The name of phys_offset is so common for global export and it may
conflict with some local name. So change phys_offset to va_pa_offset
which also used by riscv.

Also use __pa() and __va() instead of using phys_offset directly.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00
Guo Ren
205353fa06 csky: Support vmlinux bootup with MMU off
Modify SETUP_MMU macro to fit on both MMU-on or MMU-off enviornment
and vmlinux could bootup from MMU off enviornment for some cases.

Unify the style of _start and _start_smp_secondary in head.S to make
head.S looks more concise and easy to understand.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00
Mao Han
b4bf274198 csky: Add perf_arch_fetch_caller_regs support
In trace events as tracepoints context are not able to
be retrieve with task_pt_regs. Without arch caller regs
support the pt_regs context will be all zero, perf can
not parsing the callchain and resolving the symbols
correctly, some time will even get into deadlock
while handling the page fault, eg:

perf kmem —page record ls

Changelog
 - Add test case cmd in comment
 - Use regs_fp(regs) which is defined in abi/regdef.h

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
2019-04-22 13:44:57 +08:00
Guo Ren
f62e31623d csky: Support dynamic start physical address
Before this patch csky-linux need CONFIG_RAM_BASE to determine start
physical address. Now we use phys_offset variable to replace the macro
of PHYS_OFFSET and we setup phys_offset with real physical address which
is determined during startup in head.S.

With this patch we needn't re-compile kernel for different start
physical address. ie: 0x0 / 0xc0000000 start physical address could use
the same vmlinux, be care different start address must be 512MB aligned.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00
Guo Ren
bf24168293 csky: Reconstruct signal processing
Linux kernel has provided some apis for arch signal's implementation.
For example:
	restore_saved_sigmask()
	set_current_blocked()
	restore_altstack()

But in last version of csky signal.c didn't use them and some codes are
confusing, so reconstruct signal.c with reference to riscv's code.

Now csky signal.c implementation are very close to riscv and we can
get the following benefits:
 - Clear code structure
 - The signal code of riscv and csky can be reviewed together
 - Promoting the unification of arch's signal implementation

Also modified the related code in entry.S

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00
Guo Ren
f4625ee0e4 csky: Use in_syscall & forget_syscall instead of r11_sig
We could use regs->sr 16-24 bits to detect syscall: VEC_TRAP0 and
r11_sig is no necessary for current implementation.

In this patch, we implement the in_syscall and forget_syscall which are
inspired from arm & nds32, but csky pt_regs has no syscall_num element
and we just set zero to regs->sr's vector-bits-field instead.

For ret_from_fork, current task was forked from parent which is in syscall
progress and its regs->sr has been already setted with VEC_TRAP0. See:
arch/csky/kernel/process.c: copy_thread()

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
2019-04-22 13:44:57 +08:00
Guo Ren
2f7932b011 csky: Update syscall_trace_enter/exit implementation
Previous syscall_trace implementation couldn't support AUDITSYSCALL and
SYSCALL_TRACEPOINTS. Now we redesign it to support audit_syscall
and syscall_tracepoints just like other archs'.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-04-22 13:44:57 +08:00
Linus Torvalds
9ee3b3f4a5 arch/csky patches for 4.21-rc1
Here is the arch/csky patch set for the 4.21-rc1 merge window.
 Contianed in here is three features (cpu_hotplug, basic ftrace,
 basic perf) and some bugfixes.
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Merge tag 'csky-for-linus-4.21' of git://github.com/c-sky/csky-linux

Pull arch/csky updates from Guo Ren:
 "Here are three main features (cpu_hotplug, basic ftrace, basic perf)
  and some bugfixes:

  Features:
   - Add CPU-hotplug support for SMP
   - Add ftrace with function trace and function graph trace
   - Add Perf support
   - Add EM_CSKY_OLD 39
   - optimize kernel panic print.
   - remove syscall_exit_work

  Bugfixes:
   - fix abiv2 mmap(... O_SYNC) failure
   - fix gdb coredump error
   - remove vdsp implement for kernel
   - fix qemu failure to bootup sometimes
   - fix ftrace call-graph panic
   - fix device tree node reference leak
   - remove meaningless header-y
   - fix save hi,lo,dspcr regs in switch_stack
   - remove unused members in processor.h"

* tag 'csky-for-linus-4.21' of git://github.com/c-sky/csky-linux:
  csky: Add perf support for C-SKY
  csky: Add EM_CSKY_OLD 39
  clocksource/drivers/c-sky: fixup ftrace call-graph panic
  csky: ftrace call graph supported.
  csky: basic ftrace supported
  csky: remove unused members in processor.h
  csky: optimize kernel panic print.
  csky: stacktrace supported.
  csky: CPU-hotplug supported for SMP
  clocksource/drivers/c-sky: fixup qemu fail to bootup sometimes.
  csky: fixup save hi,lo,dspcr regs in switch_stack.
  csky: remove syscall_exit_work
  csky: fixup remove vdsp implement for kernel.
  csky: bugfix gdb coredump error.
  csky: fixup abiv2 mmap(... O_SYNC) failed.
  csky: define syscall_get_arch()
  elf-em.h: add EM_CSKY
  csky: remove meaningless header-y
  csky: Don't leak device tree node reference
2019-01-05 09:50:07 -08:00
Linus Torvalds
96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Guo Ren
789154c2ad csky: fixup save hi,lo,dspcr regs in switch_stack.
HI, LO, DSPCR registers are 807/810 related regs and no need for 610/860.
All of the regs must be saved in pt_regs and switch_stack. This patch
fixup saving dspcr reg in switch_stack and pt_regs.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
2018-12-31 22:57:27 +08:00
Guo Ren
2b070ccdf8 csky: fixup abiv2 mmap(... O_SYNC) failed.
Glibc function mmap(... O_SYNC) will make page to _PAGE_UNCACHE +
_PAGE_SO and strong-order page couldn't support unalignment access.
So remove _PAGE_SO from _PAGE_UNCACHE, also sync abiv1 with the macro
of _PAGE_SO.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reported-by: Liu Renwei <Renwei.Liu@verisilicon.com>
Tested-by: Yuan Qiyun <qiyun_yuan@c-sky.com>
2018-12-31 10:56:45 +08:00