| Message ID | 1454059965-23402-9-git-send-email-a.rigo@virtualopensystems.com |
|---|---|
| State | New |
| Headers | show |
Alvise Rigo <a.rigo@virtualopensystems.com> writes: > The pages set as exclusive (clean) in the DIRTY_MEMORY_EXCLUSIVE bitmap > have to have their TLB entries flagged with TLB_EXCL. The accesses to > pages with TLB_EXCL flag set have to be properly handled in that they > can potentially invalidate an open LL/SC transaction. > > Modify the TLB entries generation to honor the new bitmap and extend > the softmmu_template to handle the accesses made to guest pages marked > as exclusive. > > In the case we remove a TLB entry marked as EXCL, we unset the > corresponding exclusive bit in the bitmap. > > Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com> > Suggested-by: Claudio Fontana <claudio.fontana@huawei.com> > Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com> > --- > cputlb.c | 44 ++++++++++++++++++++++++++++-- > softmmu_template.h | 80 ++++++++++++++++++++++++++++++++++++++++++++++++------ > 2 files changed, 113 insertions(+), 11 deletions(-) > > diff --git a/cputlb.c b/cputlb.c > index ce6d720..aa9cc17 100644 > --- a/cputlb.c > +++ b/cputlb.c > @@ -395,6 +395,16 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, > env->tlb_v_table[mmu_idx][vidx] = *te; > env->iotlb_v[mmu_idx][vidx] = env->iotlb[mmu_idx][index]; > > + if (unlikely(!(te->addr_write & TLB_MMIO) && (te->addr_write & TLB_EXCL))) { > + /* We are removing an exclusive entry, set the page to dirty. This > + * is not be necessary if the vCPU has performed both SC and LL. */ > + hwaddr hw_addr = (env->iotlb[mmu_idx][index].addr & TARGET_PAGE_MASK) + > + (te->addr_write & TARGET_PAGE_MASK); > + if (!cpu->ll_sc_context) { > + cpu_physical_memory_unset_excl(hw_addr); > + } > + } > + I'm confused by the later patches removing this code and its comments about missing the setting of flags. > /* refill the tlb */ > env->iotlb[mmu_idx][index].addr = iotlb - vaddr; > env->iotlb[mmu_idx][index].attrs = attrs; > @@ -418,9 +428,19 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, > } else if (memory_region_is_ram(section->mr) > && cpu_physical_memory_is_clean(section->mr->ram_addr > + xlat)) { > - te->addr_write = address | TLB_NOTDIRTY; > - } else { > - te->addr_write = address; > + address |= TLB_NOTDIRTY; > + } > + > + /* Since the MMIO accesses follow always the slow path, we do not need > + * to set any flag to trap the access */ > + if (!(address & TLB_MMIO)) { > + if (cpu_physical_memory_is_excl(section->mr->ram_addr + xlat)) { > + /* There is at least one vCPU that has flagged the address as > + * exclusive. */ > + te->addr_write = address | TLB_EXCL; > + } else { > + te->addr_write = address; > + } Again this is confusing when following patches blat over the code. Perhaps this part of the patch should be: /* Since the MMIO accesses follow always the slow path, we do not need * to set any flag to trap the access */ if (!(address & TLB_MMIO)) { if (cpu_physical_memory_is_excl(section->mr->ram_addr + xlat)) { /* There is at least one vCPU that has flagged the address as * exclusive. */ address |= TLB_EXCL; } } te->addr_write = address; So the future patch is clearer about what it does? > } > } else { > te->addr_write = -1; > @@ -474,6 +494,24 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env1, target_ulong addr) > return qemu_ram_addr_from_host_nofail(p); > } > > +/* For every vCPU compare the exclusive address and reset it in case of a > + * match. Since only one vCPU is running at once, no lock has to be held to > + * guard this operation. */ > +static inline void lookup_and_reset_cpus_ll_addr(hwaddr addr, hwaddr size) > +{ > + CPUState *cpu; > + > + CPU_FOREACH(cpu) { > + if (cpu->excl_protected_range.begin != EXCLUSIVE_RESET_ADDR && > + ranges_overlap(cpu->excl_protected_range.begin, > + cpu->excl_protected_range.end - > + cpu->excl_protected_range.begin, > + addr, size)) { > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > + } > + } > +} > + > #define MMUSUFFIX _mmu > > /* Generates LoadLink/StoreConditional helpers in softmmu_template.h */ > diff --git a/softmmu_template.h b/softmmu_template.h > index 4332db2..267c52a 100644 > --- a/softmmu_template.h > +++ b/softmmu_template.h > @@ -474,11 +474,43 @@ void helper_le_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, > tlb_addr = env->tlb_table[mmu_idx][index].addr_write; > } > > - /* Handle an IO access. */ > + /* Handle an IO access or exclusive access. */ > if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { > - glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, > - mmu_idx, index, retaddr); > - return; > + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { From here: > + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; > + CPUState *cpu = ENV_GET_CPU(env); > + CPUClass *cc = CPU_GET_CLASS(cpu); > + /* The slow-path has been forced since we are writing to > + * exclusive-protected memory. */ > + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; > + > + /* The function lookup_and_reset_cpus_ll_addr could have reset the > + * exclusive address. Fail the SC in this case. > + * N.B.: here excl_succeed == true means that the caller is > + * helper_stcond_name in softmmu_llsc_template. > + * On the contrary, excl_succeeded == false occurs when a VCPU is > + * writing through normal store to a page with TLB_EXCL bit set. */ > + if (cpu->excl_succeeded) { > + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { > + /* The vCPU is SC-ing to an unprotected address. */ > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > + cpu->excl_succeeded = false; > + > + return; > + } > + } > + To here is repeated code later on. It would be better to have a common chunk of logic. > + glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, > + mmu_idx, index, retaddr); > + > + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); In fact if the endianess is passed to the inline function you could have a call that was: if (tlb_addr & TLB_EXCL) { glue(helper_st_name, _do_excl)(true, env, val, addr, oi, mmu_idx, index, retaddr); } and if (tlb_addr & TLB_EXCL) { glue(helper_st_name, _do_excl)(false, env, val, addr, oi, mmu_idx, index, retaddr); } later. Then future patches would just extend the single helper. > + > + return; > + } else { > + glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, > + mmu_idx, index, retaddr); > + return; > + } > } > > glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index, > @@ -586,11 +618,43 @@ void helper_be_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, > tlb_addr = env->tlb_table[mmu_idx][index].addr_write; > } > > - /* Handle an IO access. */ > + /* Handle an IO access or exclusive access. */ > if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { > - glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, > - mmu_idx, index, retaddr); > - return; > + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { > + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; > + CPUState *cpu = ENV_GET_CPU(env); > + CPUClass *cc = CPU_GET_CLASS(cpu); > + /* The slow-path has been forced since we are writing to > + * exclusive-protected memory. */ > + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; > + > + /* The function lookup_and_reset_cpus_ll_addr could have reset the > + * exclusive address. Fail the SC in this case. > + * N.B.: here excl_succeed == true means that the caller is > + * helper_stcond_name in softmmu_llsc_template. > + * On the contrary, excl_succeeded == false occurs when a VCPU is > + * writing through normal store to a page with TLB_EXCL bit set. */ > + if (cpu->excl_succeeded) { > + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { > + /* The vCPU is SC-ing to an unprotected address. */ > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > + cpu->excl_succeeded = false; > + > + return; > + } > + } > + > + glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, > + mmu_idx, index, retaddr); > + > + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); > + > + return; > + } else { > + glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, > + mmu_idx, index, retaddr); > + return; > + } > } > > glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index, -- Alex Bennée
On Tue, Feb 16, 2016 at 6:39 PM, Alex Bennée <alex.bennee@linaro.org> wrote: > > > Alvise Rigo <a.rigo@virtualopensystems.com> writes: > > > The pages set as exclusive (clean) in the DIRTY_MEMORY_EXCLUSIVE bitmap > > have to have their TLB entries flagged with TLB_EXCL. The accesses to > > pages with TLB_EXCL flag set have to be properly handled in that they > > can potentially invalidate an open LL/SC transaction. > > > > Modify the TLB entries generation to honor the new bitmap and extend > > the softmmu_template to handle the accesses made to guest pages marked > > as exclusive. > > > > In the case we remove a TLB entry marked as EXCL, we unset the > > corresponding exclusive bit in the bitmap. > > > > Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com> > > Suggested-by: Claudio Fontana <claudio.fontana@huawei.com> > > Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com> > > --- > > cputlb.c | 44 ++++++++++++++++++++++++++++-- > > softmmu_template.h | 80 ++++++++++++++++++++++++++++++++++++++++++++++++------ > > 2 files changed, 113 insertions(+), 11 deletions(-) > > > > diff --git a/cputlb.c b/cputlb.c > > index ce6d720..aa9cc17 100644 > > --- a/cputlb.c > > +++ b/cputlb.c > > @@ -395,6 +395,16 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, > > env->tlb_v_table[mmu_idx][vidx] = *te; > > env->iotlb_v[mmu_idx][vidx] = env->iotlb[mmu_idx][index]; > > > > + if (unlikely(!(te->addr_write & TLB_MMIO) && (te->addr_write & TLB_EXCL))) { > > + /* We are removing an exclusive entry, set the page to dirty. This > > + * is not be necessary if the vCPU has performed both SC and LL. */ > > + hwaddr hw_addr = (env->iotlb[mmu_idx][index].addr & TARGET_PAGE_MASK) + > > + (te->addr_write & TARGET_PAGE_MASK); > > + if (!cpu->ll_sc_context) { > > + cpu_physical_memory_unset_excl(hw_addr); > > + } > > + } > > + > > I'm confused by the later patches removing this code and its comments > about missing the setting of flags. I hope I answered to this question in the other thread. > > > > /* refill the tlb */ > > env->iotlb[mmu_idx][index].addr = iotlb - vaddr; > > env->iotlb[mmu_idx][index].attrs = attrs; > > @@ -418,9 +428,19 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, > > } else if (memory_region_is_ram(section->mr) > > && cpu_physical_memory_is_clean(section->mr->ram_addr > > + xlat)) { > > - te->addr_write = address | TLB_NOTDIRTY; > > - } else { > > - te->addr_write = address; > > + address |= TLB_NOTDIRTY; > > + } > > + > > + /* Since the MMIO accesses follow always the slow path, we do not need > > + * to set any flag to trap the access */ > > + if (!(address & TLB_MMIO)) { > > + if (cpu_physical_memory_is_excl(section->mr->ram_addr + xlat)) { > > + /* There is at least one vCPU that has flagged the address as > > + * exclusive. */ > > + te->addr_write = address | TLB_EXCL; > > + } else { > > + te->addr_write = address; > > + } > > Again this is confusing when following patches blat over the code. > Perhaps this part of the patch should be: > > /* Since the MMIO accesses follow always the slow path, we do not need > * to set any flag to trap the access */ > if (!(address & TLB_MMIO)) { > if (cpu_physical_memory_is_excl(section->mr->ram_addr + xlat)) { > /* There is at least one vCPU that has flagged the address as > * exclusive. */ > address |= TLB_EXCL; > } > } > te->addr_write = address; > > So the future patch is clearer about what it does? Yes, this is more clear. I will fix it. > > > > } > > } else { > > te->addr_write = -1; > > @@ -474,6 +494,24 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env1, target_ulong addr) > > return qemu_ram_addr_from_host_nofail(p); > > } > > > > +/* For every vCPU compare the exclusive address and reset it in case of a > > + * match. Since only one vCPU is running at once, no lock has to be held to > > + * guard this operation. */ > > +static inline void lookup_and_reset_cpus_ll_addr(hwaddr addr, hwaddr size) > > +{ > > + CPUState *cpu; > > + > > + CPU_FOREACH(cpu) { > > + if (cpu->excl_protected_range.begin != EXCLUSIVE_RESET_ADDR && > > + ranges_overlap(cpu->excl_protected_range.begin, > > + cpu->excl_protected_range.end - > > + cpu->excl_protected_range.begin, > > + addr, size)) { > > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > > + } > > + } > > +} > > + > > #define MMUSUFFIX _mmu > > > > /* Generates LoadLink/StoreConditional helpers in softmmu_template.h */ > > diff --git a/softmmu_template.h b/softmmu_template.h > > index 4332db2..267c52a 100644 > > --- a/softmmu_template.h > > +++ b/softmmu_template.h > > @@ -474,11 +474,43 @@ void helper_le_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, > > tlb_addr = env->tlb_table[mmu_idx][index].addr_write; > > } > > > > - /* Handle an IO access. */ > > + /* Handle an IO access or exclusive access. */ > > if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { > > - glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, > > - mmu_idx, index, retaddr); > > - return; > > + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { > > From here: > > > + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; > > + CPUState *cpu = ENV_GET_CPU(env); > > + CPUClass *cc = CPU_GET_CLASS(cpu); > > + /* The slow-path has been forced since we are writing to > > + * exclusive-protected memory. */ > > + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; > > + > > + /* The function lookup_and_reset_cpus_ll_addr could have reset the > > + * exclusive address. Fail the SC in this case. > > + * N.B.: here excl_succeed == true means that the caller is > > + * helper_stcond_name in softmmu_llsc_template. > > + * On the contrary, excl_succeeded == false occurs when a VCPU is > > + * writing through normal store to a page with TLB_EXCL bit set. */ > > + if (cpu->excl_succeeded) { > > + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { > > + /* The vCPU is SC-ing to an unprotected address. */ > > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > > + cpu->excl_succeeded = false; > > + > > + return; > > + } > > + } > > + > > To here is repeated code later on. It would be better to have a common > chunk of logic. > > > + glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, > > + mmu_idx, index, retaddr); > > + > > + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); > > In fact if the endianess is passed to the inline function you could have > a call that was: > > if (tlb_addr & TLB_EXCL) { > glue(helper_st_name, _do_excl)(true, env, val, addr, oi, mmu_idx, > index, retaddr); > } > > and > > if (tlb_addr & TLB_EXCL) { > glue(helper_st_name, _do_excl)(false, env, val, addr, oi, mmu_idx, > index, retaddr); > } > > later. Then future patches would just extend the single helper. OK, let's shirk down this file :) Thank you, alvise > > > > + > > + return; > > + } else { > > + glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, > > + mmu_idx, index, retaddr); > > + return; > > + } > > } > > > > glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index, > > @@ -586,11 +618,43 @@ void helper_be_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, > > tlb_addr = env->tlb_table[mmu_idx][index].addr_write; > > } > > > > - /* Handle an IO access. */ > > + /* Handle an IO access or exclusive access. */ > > if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { > > - glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, > > - mmu_idx, index, retaddr); > > - return; > > + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { > > + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; > > + CPUState *cpu = ENV_GET_CPU(env); > > + CPUClass *cc = CPU_GET_CLASS(cpu); > > + /* The slow-path has been forced since we are writing to > > + * exclusive-protected memory. */ > > + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; > > + > > + /* The function lookup_and_reset_cpus_ll_addr could have reset the > > + * exclusive address. Fail the SC in this case. > > + * N.B.: here excl_succeed == true means that the caller is > > + * helper_stcond_name in softmmu_llsc_template. > > + * On the contrary, excl_succeeded == false occurs when a VCPU is > > + * writing through normal store to a page with TLB_EXCL bit set. */ > > + if (cpu->excl_succeeded) { > > + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { > > + /* The vCPU is SC-ing to an unprotected address. */ > > + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; > > + cpu->excl_succeeded = false; > > + > > + return; > > + } > > + } > > + > > + glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, > > + mmu_idx, index, retaddr); > > + > > + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); > > + > > + return; > > + } else { > > + glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, > > + mmu_idx, index, retaddr); > > + return; > > + } > > } > > > > glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index, > > > -- > Alex Bennée
diff --git a/cputlb.c b/cputlb.c index ce6d720..aa9cc17 100644 --- a/cputlb.c +++ b/cputlb.c @@ -395,6 +395,16 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, env->tlb_v_table[mmu_idx][vidx] = *te; env->iotlb_v[mmu_idx][vidx] = env->iotlb[mmu_idx][index]; + if (unlikely(!(te->addr_write & TLB_MMIO) && (te->addr_write & TLB_EXCL))) { + /* We are removing an exclusive entry, set the page to dirty. This + * is not be necessary if the vCPU has performed both SC and LL. */ + hwaddr hw_addr = (env->iotlb[mmu_idx][index].addr & TARGET_PAGE_MASK) + + (te->addr_write & TARGET_PAGE_MASK); + if (!cpu->ll_sc_context) { + cpu_physical_memory_unset_excl(hw_addr); + } + } + /* refill the tlb */ env->iotlb[mmu_idx][index].addr = iotlb - vaddr; env->iotlb[mmu_idx][index].attrs = attrs; @@ -418,9 +428,19 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, } else if (memory_region_is_ram(section->mr) && cpu_physical_memory_is_clean(section->mr->ram_addr + xlat)) { - te->addr_write = address | TLB_NOTDIRTY; - } else { - te->addr_write = address; + address |= TLB_NOTDIRTY; + } + + /* Since the MMIO accesses follow always the slow path, we do not need + * to set any flag to trap the access */ + if (!(address & TLB_MMIO)) { + if (cpu_physical_memory_is_excl(section->mr->ram_addr + xlat)) { + /* There is at least one vCPU that has flagged the address as + * exclusive. */ + te->addr_write = address | TLB_EXCL; + } else { + te->addr_write = address; + } } } else { te->addr_write = -1; @@ -474,6 +494,24 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env1, target_ulong addr) return qemu_ram_addr_from_host_nofail(p); } +/* For every vCPU compare the exclusive address and reset it in case of a + * match. Since only one vCPU is running at once, no lock has to be held to + * guard this operation. */ +static inline void lookup_and_reset_cpus_ll_addr(hwaddr addr, hwaddr size) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + if (cpu->excl_protected_range.begin != EXCLUSIVE_RESET_ADDR && + ranges_overlap(cpu->excl_protected_range.begin, + cpu->excl_protected_range.end - + cpu->excl_protected_range.begin, + addr, size)) { + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; + } + } +} + #define MMUSUFFIX _mmu /* Generates LoadLink/StoreConditional helpers in softmmu_template.h */ diff --git a/softmmu_template.h b/softmmu_template.h index 4332db2..267c52a 100644 --- a/softmmu_template.h +++ b/softmmu_template.h @@ -474,11 +474,43 @@ void helper_le_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, tlb_addr = env->tlb_table[mmu_idx][index].addr_write; } - /* Handle an IO access. */ + /* Handle an IO access or exclusive access. */ if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { - glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, - mmu_idx, index, retaddr); - return; + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; + CPUState *cpu = ENV_GET_CPU(env); + CPUClass *cc = CPU_GET_CLASS(cpu); + /* The slow-path has been forced since we are writing to + * exclusive-protected memory. */ + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; + + /* The function lookup_and_reset_cpus_ll_addr could have reset the + * exclusive address. Fail the SC in this case. + * N.B.: here excl_succeed == true means that the caller is + * helper_stcond_name in softmmu_llsc_template. + * On the contrary, excl_succeeded == false occurs when a VCPU is + * writing through normal store to a page with TLB_EXCL bit set. */ + if (cpu->excl_succeeded) { + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { + /* The vCPU is SC-ing to an unprotected address. */ + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; + cpu->excl_succeeded = false; + + return; + } + } + + glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, + mmu_idx, index, retaddr); + + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); + + return; + } else { + glue(helper_le_st_name, _do_mmio_access)(env, val, addr, oi, + mmu_idx, index, retaddr); + return; + } } glue(helper_le_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index, @@ -586,11 +618,43 @@ void helper_be_st_name(CPUArchState *env, target_ulong addr, DATA_TYPE val, tlb_addr = env->tlb_table[mmu_idx][index].addr_write; } - /* Handle an IO access. */ + /* Handle an IO access or exclusive access. */ if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) { - glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, - mmu_idx, index, retaddr); - return; + if ((tlb_addr & ~TARGET_PAGE_MASK) == TLB_EXCL) { + CPUIOTLBEntry *iotlbentry = &env->iotlb[mmu_idx][index]; + CPUState *cpu = ENV_GET_CPU(env); + CPUClass *cc = CPU_GET_CLASS(cpu); + /* The slow-path has been forced since we are writing to + * exclusive-protected memory. */ + hwaddr hw_addr = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; + + /* The function lookup_and_reset_cpus_ll_addr could have reset the + * exclusive address. Fail the SC in this case. + * N.B.: here excl_succeed == true means that the caller is + * helper_stcond_name in softmmu_llsc_template. + * On the contrary, excl_succeeded == false occurs when a VCPU is + * writing through normal store to a page with TLB_EXCL bit set. */ + if (cpu->excl_succeeded) { + if (!cc->cpu_valid_excl_access(cpu, hw_addr, DATA_SIZE)) { + /* The vCPU is SC-ing to an unprotected address. */ + cpu->excl_protected_range.begin = EXCLUSIVE_RESET_ADDR; + cpu->excl_succeeded = false; + + return; + } + } + + glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, + mmu_idx, index, retaddr); + + lookup_and_reset_cpus_ll_addr(hw_addr, DATA_SIZE); + + return; + } else { + glue(helper_be_st_name, _do_mmio_access)(env, val, addr, oi, + mmu_idx, index, retaddr); + return; + } } glue(helper_be_st_name, _do_ram_access)(env, val, addr, oi, mmu_idx, index,
The pages set as exclusive (clean) in the DIRTY_MEMORY_EXCLUSIVE bitmap have to have their TLB entries flagged with TLB_EXCL. The accesses to pages with TLB_EXCL flag set have to be properly handled in that they can potentially invalidate an open LL/SC transaction. Modify the TLB entries generation to honor the new bitmap and extend the softmmu_template to handle the accesses made to guest pages marked as exclusive. In the case we remove a TLB entry marked as EXCL, we unset the corresponding exclusive bit in the bitmap. Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com> Suggested-by: Claudio Fontana <claudio.fontana@huawei.com> Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com> --- cputlb.c | 44 ++++++++++++++++++++++++++++-- softmmu_template.h | 80 ++++++++++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 113 insertions(+), 11 deletions(-)