On Thu, 2019-07-11 at 22:57 +1000, Michael Ellerman wrote:
> Claudio Carvalho <cclaudio@xxxxxxxxxxxxx> writes:
> > From: Michael Anderson <andmike@xxxxxxxxxxxxx>
> >
> > When running under an ultravisor, the ultravisor controls the real
> > partition table and has it in secure memory where the hypervisor
> > can't
> > access it, and therefore we (the HV) have to do a ucall whenever we
> > want
> > to update an entry.
> >
> > The HV still keeps a copy of its view of the partition table in
> > normal
> > memory so that the nest MMU can access it.
> >
> > Both partition tables will have PATE entries for HV and normal
> > virtual
>
> Can you expand novel acronyms on their first usage please, ie. PATE.
>
Agreed. This confused me a while ago. It is "Partition Table Entry",
correct?
> > machines.
> >
> > Suggested-by: Ryan Grimm <grimm@xxxxxxxxxxxxxxxxxx>
>
Please remove this and add
Reviewed-by: Ryan Grimm <grimm@xxxxxxxxxxxxx>
> "Suggested" implies this is optional, but it's not :)
>
> I'm not sure exactly what Ryan's input was, but feel free to make up
> a
> better tag :)
>
> > Signed-off-by: Michael Anderson <andmike@xxxxxxxxxxxxx>
> > Signed-off-by: Madhavan Srinivasan <maddy@xxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
> > [ Write the pate in HV's table before doing that in UV's ]
> > Signed-off-by: Claudio Carvalho <cclaudio@xxxxxxxxxxxxx>
> > ---
> > arch/powerpc/include/asm/ultravisor-api.h | 5 +++-
> > arch/powerpc/include/asm/ultravisor.h | 14 ++++++++++
> > arch/powerpc/mm/book3s64/hash_utils.c | 3 +-
> > arch/powerpc/mm/book3s64/pgtable.c | 34
> > +++++++++++++++++++++--
> > arch/powerpc/mm/book3s64/radix_pgtable.c | 9 ++++--
> > 5 files changed, 57 insertions(+), 8 deletions(-)
> >
> > diff --git a/arch/powerpc/include/asm/ultravisor-api.h
> > b/arch/powerpc/include/asm/ultravisor-api.h
> > index 49e766adabc7..141940771add 100644
> > --- a/arch/powerpc/include/asm/ultravisor-api.h
> > +++ b/arch/powerpc/include/asm/ultravisor-api.h
> > @@ -15,6 +15,9 @@
> > #define U_SUCCESS H_SUCCESS
> > #define U_FUNCTION H_FUNCTION
> > #define U_PARAMETER H_PARAMETER
> > +#define U_PERMISSION H_PERMISSION
> >
> > -#endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
>
> What happened there? Just a diff artifact?
>
> > +/* opcodes */
> > +#define UV_WRITE_PATE 0xF104
> >
> > +#endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
> > diff --git a/arch/powerpc/include/asm/ultravisor.h
> > b/arch/powerpc/include/asm/ultravisor.h
> > index a78a2dacfd0b..996c1efd6c6d 100644
> > --- a/arch/powerpc/include/asm/ultravisor.h
> > +++ b/arch/powerpc/include/asm/ultravisor.h
> > @@ -12,6 +12,8 @@
> >
> > #if !defined(__ASSEMBLY__)
> >
> > +#include <linux/types.h>
> > +
> > /* Internal functions */
> > extern int early_init_dt_scan_ultravisor(unsigned long node, const
> > char *uname,
> > int depth, void *data);
> > @@ -28,8 +30,20 @@ extern int
> > early_init_dt_scan_ultravisor(unsigned long node, const char
> > *uname,
> > */
> > #if defined(CONFIG_PPC_POWERNV)
> > long ucall(unsigned long opcode, unsigned long *retbuf, ...);
> > +#else
> > +static long ucall(unsigned long opcode, unsigned long *retbuf,
> > ...)
>
> ^
> inline
>
> > +{
> > + return U_NOT_AVAILABLE;
> > +}
> > #endif
>
> That should have been in the previous patch.
>
> > +static inline int uv_register_pate(u64 lpid, u64 dw0, u64 dw1)
> > +{
> > + unsigned long retbuf[UCALL_BUFSIZE];
> > +
> > + return ucall(UV_WRITE_PATE, retbuf, lpid, dw0, dw1);
>
> You probably want a ucall_norets().
>
> > +}
> > +
> > #endif /* !__ASSEMBLY__ */
> >
> > #endif /* _ASM_POWERPC_ULTRAVISOR_H */
> > diff --git a/arch/powerpc/mm/book3s64/hash_utils.c
> > b/arch/powerpc/mm/book3s64/hash_utils.c
> > index 1ff451892d7f..220a4e133240 100644
> > --- a/arch/powerpc/mm/book3s64/hash_utils.c
> > +++ b/arch/powerpc/mm/book3s64/hash_utils.c
> > @@ -1080,9 +1080,10 @@ void hash__early_init_mmu_secondary(void)
> >
> > if (!cpu_has_feature(CPU_FTR_ARCH_300))
> > mtspr(SPRN_SDR1, _SDR1);
> > - else
> > + else if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR))
> > mtspr(SPRN_PTCR,
> > __pa(partition_tb) | (PATB_SIZE_SHIFT -
> > 12));
>
> Needs a comment for the else case.
>
> > }
> > /* Initialize SLB */
> > slb_initialize();
> > diff --git a/arch/powerpc/mm/book3s64/pgtable.c
> > b/arch/powerpc/mm/book3s64/pgtable.c
> > index ad3dd977c22d..224c5c7c2e3d 100644
> > --- a/arch/powerpc/mm/book3s64/pgtable.c
> > +++ b/arch/powerpc/mm/book3s64/pgtable.c
> > @@ -16,6 +16,8 @@
> > #include <asm/tlb.h>
> > #include <asm/trace.h>
> > #include <asm/powernv.h>
> > +#include <asm/firmware.h>
> > +#include <asm/ultravisor.h>
> >
> > #include <mm/mmu_decl.h>
> > #include <trace/events/thp.h>
> > @@ -206,12 +208,25 @@ void __init mmu_partition_table_init(void)
> > * 64 K size.
> > */
> > ptcr = __pa(partition_tb) | (PATB_SIZE_SHIFT - 12);
> > - mtspr(SPRN_PTCR, ptcr);
> > + /*
> > + * If ultravisor is available, it is responsible for creating
> > and
> > + * managing partition table
> > + */
>
> But we just created the partition table?!
>
> This comment and the one below would probably make more sense if they
> were merged and appeared further up, where we allocate the partition
> table.
>
> > + if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR))
> > + mtspr(SPRN_PTCR, ptcr);
> > +
> > + /*
> > + * Since nestMMU cannot access secure memory. Create
> > + * and manage our own partition table. This table
>
> But we just said the UV was responsible for it :)
>
> > + * contains entries for nonsecure and hypervisor
> > + * partition.
> > + */
> > powernv_set_nmmu_ptcr(ptcr);
> > }
> >
> > -void mmu_partition_table_set_entry(unsigned int lpid, unsigned
> > long dw0,
> > - unsigned long dw1)
> > +static void __mmu_partition_table_set_entry(unsigned int lpid,
> > + unsigned long dw0,
> > + unsigned long dw1)
> > {
> > unsigned long old = be64_to_cpu(partition_tb[lpid].patb0);
> >
> > @@ -238,6 +253,19 @@ void mmu_partition_table_set_entry(unsigned
> > int lpid, unsigned long dw0,
> > /* do we need fixup here ?*/
> > asm volatile("eieio; tlbsync; ptesync" : : : "memory");
> > }
> > +
> > +void mmu_partition_table_set_entry(unsigned int lpid, unsigned
> > long dw0,
> > + unsigned long dw1)
> > +{
> > + __mmu_partition_table_set_entry(lpid, dw0, dw1);
> > +
> > + if (firmware_has_feature(FW_FEATURE_ULTRAVISOR)) {
> > + uv_register_pate(lpid, dw0, dw1);
> > + pr_info("PATE registered by ultravisor: dw0 = 0x%lx,
> > dw1 = 0x%lx\n",
> > + dw0, dw1);
> > + }
> > +}
>
> I agree with Alexey that this patch and the next should be merged and
> the result cleaned up a bit.
>
> > +
>
> No extra blank please.
>
> > EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry);
> >
> > static pmd_t *get_pmd_from_cache(struct mm_struct *mm)
> > diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c
> > b/arch/powerpc/mm/book3s64/radix_pgtable.c
> > index 8904aa1243d8..da6a6b76a040 100644
> > --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> > +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> > @@ -656,8 +656,10 @@ void radix__early_init_mmu_secondary(void)
> > lpcr = mfspr(SPRN_LPCR);
> > mtspr(SPRN_LPCR, lpcr | LPCR_UPRT | LPCR_HR);
> >
> > - mtspr(SPRN_PTCR,
> > - __pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
> > + if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR))
> > + mtspr(SPRN_PTCR, __pa(partition_tb) |
> > + (PATB_SIZE_SHIFT - 12));
> > +
> > radix_init_amor();
> > }
> >
> > @@ -673,7 +675,8 @@ void radix__mmu_cleanup_all(void)
> > if (!firmware_has_feature(FW_FEATURE_LPAR)) {
> > lpcr = mfspr(SPRN_LPCR);
> > mtspr(SPRN_LPCR, lpcr & ~LPCR_UPRT);
> > - mtspr(SPRN_PTCR, 0);
> > + if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR))
> > + mtspr(SPRN_PTCR, 0);
> > powernv_set_nmmu_ptcr(0);
> > radix__flush_tlb_all();
> > }
>
> There's four of these case where we skip touching the PTCR, which is
> right on the borderline of warranting an accessor. I guess we can do
> it
> as a cleanup later.
>
> cheers
>
