linux/arch
Mingwei Zhang bb2baeb214 KVM: SVM: improve the code readability for ASID management
KVM SEV code uses bitmaps to manage ASID states. ASID 0 was always skipped
because it is never used by VM. Thus, in existing code, ASID value and its
bitmap postion always has an 'offset-by-1' relationship.

Both SEV and SEV-ES shares the ASID space, thus KVM uses a dynamic range
[min_asid, max_asid] to handle SEV and SEV-ES ASIDs separately.

Existing code mixes the usage of ASID value and its bitmap position by
using the same variable called 'min_asid'.

Fix the min_asid usage: ensure that its usage is consistent with its name;
allocate extra size for ASID 0 to ensure that each ASID has the same value
with its bitmap position. Add comments on ASID bitmap allocation to clarify
the size change.

Signed-off-by: Mingwei Zhang <mizhang@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Marc Orr <marcorr@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Alper Gun <alpergun@google.com>
Cc: Dionna Glaze <dionnaglaze@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vipin Sharma <vipinsh@google.com>
Cc: Peter Gonda <pgonda@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Message-Id: <20210802180903.159381-1-mizhang@google.com>
[Fix up sev_asid_free to also index by ASID, as suggested by Sean
 Christopherson, and use nr_asids in sev_cpu_init. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-04 09:43:03 -04:00
..
alpha Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
arc Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
arm ARM: SoC fixes for v5.14 2021-07-17 15:58:24 -07:00
arm64 KVM/arm64 fixes for 5.14, take #1 2021-07-19 10:05:40 -04:00
csky Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
h8300 Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
hexagon Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
ia64 Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
m68k Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
microblaze Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
mips Merge tag 'kvm-s390-master-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD 2021-07-14 12:14:27 -04:00
nds32 Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
nios2 Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
openrisc Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
parisc Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
powerpc Merge tag 'kvm-s390-master-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD 2021-07-14 12:14:27 -04:00
riscv Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
s390 KVM: s390: restore old debugfs names 2021-07-27 16:59:00 -04:00
sh Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
sparc Locking fixes: 2021-07-11 11:06:09 -07:00
um Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
x86 KVM: SVM: improve the code readability for ASID management 2021-08-04 09:43:03 -04:00
xtensa Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
.gitignore
Kconfig Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR 2021-06-22 11:07:18 -07:00