(pre-requisite to make the next patches more palatable)

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This reverts commit 33f00dcedb0e22cdb156a23632814fc580fcfcf8.

    While it was a good idea to try to use the mm/vmalloc.c allocator instead
    of our own (in fact, ours is itself a dup on an old variant of the vmalloc
    one), unfortunately, the approach is terminally busted since
    dma_alloc_coherent() can be called at interrupt time or in atomic contexts
    and there's little chances we'll make the code in mm/vmalloc.c cope with\       that :-(

    Until we can get the generic code to forbid that idiocy and fix all
    drivers abusing it, we pretty much have no choice but revert to
    our custom virtual space allocator.

    There's also a problem with SMP safety since freeing such mapping
    would require an IPI which cannot be done at interrupt time.

    However, right now, I don't think we support any platform that is
    both SMP and has non-coherent DMA (don't laugh, I know such things
    do exist !) so we can sort that out later.

    Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes a regression introduced by commit
a4e22f02f5b6518c1484faea1f88d81802b9feac ("powerpc: Update 64bit
__copy_tofrom_user() using CPU_FTR_UNALIGNED_LD_STD").

The same bug that existed in the 64bit memcpy() also exists here so fix
it here too. The fix is the same as that applied to memcpy() with the
addition of fixes for the exception handling code required for
__copy_tofrom_user().

This stops us reading beyond the end of the source region we were told
to copy.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This fixes a regression introduced by commit
25d6e2d7c58ddc4a3b614fc5381591c0cfe66556 ("powerpc: Update 64bit memcpy()
using CPU_FTR_UNALIGNED_LD_STD").

This commit allowed CPUs that have the CPU_FTR_UNALIGNED_LD_STD CPU
feature bit present to do the memcpy() with unaligned load doubles. But,
along with this came a bug where our final load double would read bytes
beyond a page boundary and into the next (unmapped) page. This was caught
by enabling CONFIG_DEBUG_PAGEALLOC,

The fix was to read only the number of bytes that we need to store rather
than reading a full 8-byte doubleword and storing only a portion of that.

In order to minimise the amount of existing code touched we use the
original do_tail for the src_unaligned case.

Below is an example of the regression, as reported by Sachin Sant:

Unable to handle kernel paging request for data at address 0xc00000003f380000
Faulting instruction address: 0xc000000000039574
cpu 0x1: Vector: 300 (Data Access) at [c00000003baf3020]
    pc: c000000000039574: .memcpy+0x74/0x244
    lr: d00000000244916c: .ext3_xattr_get+0x288/0x2f4 [ext3]
    sp: c00000003baf32a0
   msr: 8000000000009032
   dar: c00000003f380000
 dsisr: 40000000
  current = 0xc00000003e54b010
  paca    = 0xc000000000a53680
    pid   = 1840, comm = readahead
enter ? for help
[link register   ] d00000000244916c .ext3_xattr_get+0x288/0x2f4 [ext3]
[c00000003baf32a0] d000000002449104 .ext3_xattr_get+0x220/0x2f4 [ext3]
(unreliab
le)
[c00000003baf3390] d00000000244a6e8 .ext3_xattr_security_get+0x40/0x5c [ext3]
[c00000003baf3400] c000000000148154 .generic_getxattr+0x74/0x9c
[c00000003baf34a0] c000000000333400 .inode_doinit_with_dentry+0x1c4/0x678
[c00000003baf3560] c00000000032c6b0 .security_d_instantiate+0x50/0x68
[c00000003baf35e0] c00000000013c818 .d_instantiate+0x78/0x9c
[c00000003baf3680] c00000000013ced0 .d_splice_alias+0xf0/0x120
[c00000003baf3720] d00000000243e05c .ext3_lookup+0xec/0x134 [ext3]
[c00000003baf37c0] c000000000131e74 .do_lookup+0x110/0x260
[c00000003baf3880] c000000000134ed0 .__link_path_walk+0xa98/0x1010
[c00000003baf3970] c0000000001354a0 .path_walk+0x58/0xc4
[c00000003baf3a20] c000000000135720 .do_path_lookup+0x138/0x1e4
[c00000003baf3ad0] c00000000013645c .path_lookup_open+0x6c/0xc8
[c00000003baf3b70] c000000000136780 .do_filp_open+0xcc/0x874
[c00000003baf3d10] c0000000001251e0 .do_sys_open+0x80/0x140
[c00000003baf3dc0] c00000000016aaec .compat_sys_open+0x24/0x38
[c00000003baf3e30] c00000000000855c syscall_exit+0x0/0x40

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch rewrites consistent dma allocations support to use vmalloc
layer to allocate virtual memory space from vmalloc pool and get rid
of CONFIG_CONSISTENT_{START,SIZE}.

This greatly simplifies the code by effectively removing a custom
allocator we had for virtual space.

Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Create a new header that becomes a single location for defining PowerPC
opcodes used by code that is either generationg instructions
at runtime (fixups, debug, etc.), emulating instructions, or just
compiling instructions old assemblers don't know about.

We currently don't handle the floating point emulation or alignment decode
as both are better handled by the specific decode support they already
have.

Added support for the new dcbzl, dcbal, msgsnd, tlbilx, & wait instructions
since older assemblers don't know about them.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Currently emulate_step() emulates mr. instructions without updating cr0
and this can be disastrous. Don't emulate mr.

This bug has been around for a while, but I am not sure if its a worthy
-stable candidate. I'll leave it to Ben do decide.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (144 commits)
  powerpc/44x: Support 16K/64K base page sizes on 44x
  powerpc: Force memory size to be a multiple of PAGE_SIZE
  powerpc/32: Wire up the trampoline code for kdump
  powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M
  powerpc/32: Allow __ioremap on RAM addresses for kdump kernel
  powerpc/32: Setup OF properties for kdump
  powerpc/32/kdump: Implement crash_setup_regs() using ppc_save_regs()
  powerpc: Prepare xmon_save_regs for use with kdump
  powerpc: Remove default kexec/crash_kernel ops assignments
  powerpc: Make default kexec/crash_kernel ops implicit
  powerpc: Setup OF properties for ppc32 kexec
  powerpc/pseries: Fix cpu hotplug
  powerpc: Fix KVM build on ppc440
  powerpc/cell: add QPACE as a separate Cell platform
  powerpc/cell: fix build breakage with CONFIG_SPUFS disabled
  powerpc/mpc5200: fix error paths in PSC UART probe function
  powerpc/mpc5200: add rts/cts handling in PSC UART driver
  powerpc/mpc5200: Make PSC UART driver update serial errors counters
  powerpc/mpc5200: Remove obsolete code from mpc5200 MDIO driver
  powerpc/mpc5200: Add MDMA/UDMA support to MPC5200 ATA driver
  ...

Fix trivial conflict in drivers/char/Makefile as per Paul's directions

Rename PowerPC's struct vm_region so that I can introduce my own
global version for NOMMU.  It's feasible that the PowerPC version may
wish to use my global one instead.

The NOMMU vm_region struct defines areas of the physical memory map
that are under mmap.  This may include chunks of RAM or regions of
memory mapped devices, such as flash.  It is also used to retain
copies of file content so that shareable private memory mappings of
files can be made.  As such, it may be compatible with what is
described in the banner comment for PowerPC's vm_region struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>