kernel.git/arch/s390/kernel/vdso.c, branch linux-4.6.y

s390/vdso: optimize getcpu system call

2016-01-11T12:01:24Z

Add the CPU number to the per-cpu vdso data page and add the __kernel_getcpu function to the vdso object to retrieve the CPU number in user space. Suggested-by: Heiko Carstens Reviewed-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: drop smp_mb in vdso_init

2016-01-11T11:27:22Z

The initial s390 vdso code is heavily influenced by the powerpc version which does have a smp_wmb in vdso_init right before the vdso_ready=1 assignment. s390 has no need for that. Signed-off-by: Michael S. Tsirkin Message-Id: <1452010645-25380-1-git-send-email-mst@redhat.com> Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky

s390: rename struct _lowcore to struct lowcore

2016-01-11T11:27:15Z

Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/vdso: use correct memory barrier

2015-10-14T12:32:01Z

By definition smp_wmb only orders writes against writes. (Finish all previous writes, and do not start any future write). To protect the vdso init code against early reads on other CPUs, let's use a full smp_mb at the end of vdso init. As right now smp_wmb is implemented as full serialization, this needs no stable backport, but this change will be necessary if we reimplement smp_wmb. Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky

s390: remove 31 bit support

2015-03-25T10:49:33Z

Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area

2014-08-08T22:57:27Z

The core mm code will provide a default gate area based on FIXADDR_USER_START and FIXADDR_USER_END if !defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR). This default is only useful for ia64. arm64, ppc, s390, sh, tile, 64-bit UML, and x86_32 have their own code just to disable it. arm, 32-bit UML, and x86_64 have gate areas, but they have their own implementations. This gets rid of the default and moves the code into ia64. This should save some code on architectures without a gate area: it's now possible to inline the gate_area functions in the default case. Signed-off-by: Andy Lutomirski Acked-by: Nathan Lynch Acked-by: H. Peter Anvin Acked-by: Benjamin Herrenschmidt [in principle] Acked-by: Richard Weinberger [for um] Acked-by: Will Deacon [for arm64] Cc: Catalin Marinas Cc: Will Deacon Cc: Tony Luck Cc: Fenghua Yu Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Chris Metcalf Cc: Jeff Dike Cc: Richard Weinberger Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Nathan Lynch Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

s390/vdso: fix access-list entry initialization

2013-12-02T14:31:09Z

The access-list entry is supposed to have the fetch-only bit set, however a reserved bit got set instead. Userspace isn't able to write to the page anyway since the accessed page has the read-only bit set. So this saves us only for bad surprises in the future if the reserved bit gets used. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/uaccess: always run the kernel in home space

2013-10-24T15:16:57Z

Simplify the uaccess code by removing the user_mode=home option. The kernel will now always run in the home space mode. Signed-off-by: Martin Schwidefsky

s390/mm: cleanup page table definitions

2013-08-22T10:20:06Z

Improve the encoding of the different pte types and the naming of the page, segment table and region table bits. Due to the different pte encoding the hugetlbfs primitives need to be adapted as well. To improve compatability with common code make the huge ptes use the encoding of normal ptes. The conversion between the pte and pmd encoding for a huge pte is done with set_huge_pte_at and huge_ptep_get. Overall the code is now easier to understand. Reviewed-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky

s390: replace remaining strict_strtoul() with kstrtoul()

2013-08-22T10:20:00Z

Replace the last two strict_strtoul() with kstrtoul(). Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky