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tcg: Factor out probe_write() logic into probe_access()
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Let's also allow to probe other access types.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190830100959.26615-3-david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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davidhildenbrand authored and rth7680 committed Sep 3, 2019
1 parent fef39cc commit c25c283
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Showing 3 changed files with 60 additions and 19 deletions.
43 changes: 32 additions & 11 deletions accel/tcg/cputlb.c
Expand Up @@ -1075,30 +1075,51 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr)
return qemu_ram_addr_from_host_nofail(p);
}

/* Probe for whether the specified guest write access is permitted.
* If it is not permitted then an exception will be taken in the same
* way as if this were a real write access (and we will not return).
/*
* Probe for whether the specified guest access is permitted. If it is not
* permitted then an exception will be taken in the same way as if this
* were a real access (and we will not return).
* If the size is 0 or the page requires I/O access, returns NULL; otherwise,
* returns the address of the host page similar to tlb_vaddr_to_host().
*/
void *probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
uintptr_t retaddr)
void *probe_access(CPUArchState *env, target_ulong addr, int size,
MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
{
uintptr_t index = tlb_index(env, mmu_idx, addr);
CPUTLBEntry *entry = tlb_entry(env, mmu_idx, addr);
target_ulong tlb_addr = tlb_addr_write(entry);
target_ulong tlb_addr;
size_t elt_ofs;
int wp_access;

g_assert(-(addr | TARGET_PAGE_MASK) >= size);

switch (access_type) {
case MMU_DATA_LOAD:
elt_ofs = offsetof(CPUTLBEntry, addr_read);
wp_access = BP_MEM_READ;
break;
case MMU_DATA_STORE:
elt_ofs = offsetof(CPUTLBEntry, addr_write);
wp_access = BP_MEM_WRITE;
break;
case MMU_INST_FETCH:
elt_ofs = offsetof(CPUTLBEntry, addr_code);
wp_access = BP_MEM_READ;
break;
default:
g_assert_not_reached();
}
tlb_addr = tlb_read_ofs(entry, elt_ofs);

if (unlikely(!tlb_hit(tlb_addr, addr))) {
if (!VICTIM_TLB_HIT(addr_write, addr)) {
tlb_fill(env_cpu(env), addr, size, MMU_DATA_STORE,
mmu_idx, retaddr);
if (!victim_tlb_hit(env, mmu_idx, index, elt_ofs,
addr & TARGET_PAGE_MASK)) {
tlb_fill(env_cpu(env), addr, size, access_type, mmu_idx, retaddr);
/* TLB resize via tlb_fill may have moved the entry. */
index = tlb_index(env, mmu_idx, addr);
entry = tlb_entry(env, mmu_idx, addr);
}
tlb_addr = tlb_addr_write(entry);
tlb_addr = tlb_read_ofs(entry, elt_ofs);
}

if (!size) {
Expand All @@ -1109,7 +1130,7 @@ void *probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
if (tlb_addr & TLB_WATCHPOINT) {
cpu_check_watchpoint(env_cpu(env), addr, size,
env_tlb(env)->d[mmu_idx].iotlb[index].attrs,
BP_MEM_WRITE, retaddr);
wp_access, retaddr);
}

if (tlb_addr & (TLB_NOTDIRTY | TLB_MMIO)) {
Expand Down
26 changes: 20 additions & 6 deletions accel/tcg/user-exec.c
Expand Up @@ -188,17 +188,31 @@ static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info,
g_assert_not_reached();
}

void *probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
uintptr_t retaddr)
void *probe_access(CPUArchState *env, target_ulong addr, int size,
MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
{
int flags;

g_assert(-(addr | TARGET_PAGE_MASK) >= size);

if (!guest_addr_valid(addr) ||
page_check_range(addr, size, PAGE_WRITE) < 0) {
switch (access_type) {
case MMU_DATA_STORE:
flags = PAGE_WRITE;
break;
case MMU_DATA_LOAD:
flags = PAGE_READ;
break;
case MMU_INST_FETCH:
flags = PAGE_EXEC;
break;
default:
g_assert_not_reached();
}

if (!guest_addr_valid(addr) || page_check_range(addr, size, flags) < 0) {
CPUState *cpu = env_cpu(env);
CPUClass *cc = CPU_GET_CLASS(cpu);

cc->tlb_fill(cpu, addr, size, MMU_DATA_STORE, MMU_USER_IDX, false,
cc->tlb_fill(cpu, addr, size, access_type, MMU_USER_IDX, false,
retaddr);
g_assert_not_reached();
}
Expand Down
10 changes: 8 additions & 2 deletions include/exec/exec-all.h
Expand Up @@ -310,8 +310,14 @@ static inline void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *cpu,
{
}
#endif
void *probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
uintptr_t retaddr);
void *probe_access(CPUArchState *env, target_ulong addr, int size,
MMUAccessType access_type, int mmu_idx, uintptr_t retaddr);

static inline void *probe_write(CPUArchState *env, target_ulong addr, int size,
int mmu_idx, uintptr_t retaddr)
{
return probe_access(env, addr, size, MMU_DATA_STORE, mmu_idx, retaddr);
}

#define CODE_GEN_ALIGN 16 /* must be >= of the size of a icache line */

Expand Down

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