From: Christoph Muellner <cmuell...@linux.com> The existing probe_access* functions do not allow to specify the access size and a non-faulting behavior at the same time.
This is resolved by adding a generalization of probe_access_flags() that takes an additional size parameter. The semantics is basically the same as probe_access_flags(), but instead of assuming an access to any byte of the addressed page, we can restrict to access to a specific area, like probe_access() allows. Signed-off-by: Christoph Muellner <cmuell...@linux.com> --- accel/tcg/cputlb.c | 19 +++++++++++++++++++ accel/tcg/user-exec.c | 15 ++++++++++++--- include/exec/exec-all.h | 24 ++++++++++++++++++++++++ 3 files changed, 55 insertions(+), 3 deletions(-) diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index 4812d83961..dd3bc7a356 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -1606,6 +1606,25 @@ int probe_access_full(CPUArchState *env, target_ulong addr, return flags; } +int probe_access_range_flags(CPUArchState *env, target_ulong addr, + int size, MMUAccessType access_type, + int mmu_idx, bool nonfault, void **phost, + uintptr_t retaddr) +{ + CPUTLBEntryFull *full; + int flags = probe_access_internal(env, addr, size, access_type, + mmu_idx, nonfault, phost, &full, + retaddr); + + /* Handle clean RAM pages. */ + if (unlikely(flags & TLB_NOTDIRTY)) { + notdirty_write(env_cpu(env), addr, 1, full, retaddr); + flags &= ~TLB_NOTDIRTY; + } + + return flags; +} + int probe_access_flags(CPUArchState *env, target_ulong addr, MMUAccessType access_type, int mmu_idx, bool nonfault, void **phost, uintptr_t retaddr) diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c index ae67d84638..a73c840655 100644 --- a/accel/tcg/user-exec.c +++ b/accel/tcg/user-exec.c @@ -761,9 +761,10 @@ static int probe_access_internal(CPUArchState *env, target_ulong addr, cpu_loop_exit_sigsegv(env_cpu(env), addr, access_type, maperr, ra); } -int probe_access_flags(CPUArchState *env, target_ulong addr, - MMUAccessType access_type, int mmu_idx, - bool nonfault, void **phost, uintptr_t ra) +int probe_access_range_flags(CPUArchState *env, target_ulong addr, + int size, MMUAccessType access_type, + int mmu_idx, bool nonfault, void **phost, + uintptr_t ra) { int flags; @@ -772,6 +773,14 @@ int probe_access_flags(CPUArchState *env, target_ulong addr, return flags; } +int probe_access_flags(CPUArchState *env, target_ulong addr, + MMUAccessType access_type, int mmu_idx, + bool nonfault, void **phost, uintptr_t ra) +{ + return probe_access_range_flags(env, addr, 0, access_type, mmu_idx, + nonfault, phost, ra); +} + void *probe_access(CPUArchState *env, target_ulong addr, int size, MMUAccessType access_type, int mmu_idx, uintptr_t ra) { diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h index 54585a9954..b75f15f247 100644 --- a/include/exec/exec-all.h +++ b/include/exec/exec-all.h @@ -442,6 +442,30 @@ static inline void *probe_read(CPUArchState *env, target_ulong addr, int size, return probe_access(env, addr, size, MMU_DATA_LOAD, mmu_idx, retaddr); } +/** + * probe_access_range_flags: + * @env: CPUArchState + * @addr: guest virtual address to look up + * @size: size of the access + * @access_type: read, write or execute permission + * @mmu_idx: MMU index to use for lookup + * @nonfault: suppress the fault + * @phost: return value for host address + * @retaddr: return address for unwinding + * + * Similar to probe_access, loosely returning the TLB_FLAGS_MASK for + * the access range, and storing the host address for RAM in @phost. + * + * If @nonfault is set, do not raise an exception but return TLB_INVALID_MASK. + * Do not handle watchpoints, but include TLB_WATCHPOINT in the returned flags. + * Do handle clean pages, so exclude TLB_NOTDIRTY from the returned flags. + * For simplicity, all "mmio-like" flags are folded to TLB_MMIO. + */ +int probe_access_range_flags(CPUArchState *env, target_ulong addr, + int size, MMUAccessType access_type, + int mmu_idx, bool nonfault, void **phost, + uintptr_t retaddr); + /** * probe_access_flags: * @env: CPUArchState -- 2.39.2