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author | Paolo Bonzini <pbonzini@redhat.com> | 2015-03-18 14:21:43 +0100 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2015-04-30 16:55:32 +0200 |
commit | 41063e1e7afcb2f13e103720fe96221657f5dbbc (patch) | |
tree | ce78dca7d90917ffc9bfe45fcec5dfba0f8a9320 /exec.c | |
parent | 4c6637525290dc863a00be7f58fc11d07b780bd4 (diff) | |
download | qemu-41063e1e7afcb2f13e103720fe96221657f5dbbc.zip qemu-41063e1e7afcb2f13e103720fe96221657f5dbbc.tar.gz qemu-41063e1e7afcb2f13e103720fe96221657f5dbbc.tar.bz2 |
exec: move rcu_read_lock/unlock to address_space_translate callers
Once address_space_translate will be called outside the BQL, the returned
MemoryRegion might disappear as soon as the RCU read-side critical section
ends. Avoid this by moving the critical section to the callers.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1426684909-95030-3-git-send-email-pbonzini@redhat.com>
Diffstat (limited to 'exec.c')
-rw-r--r-- | exec.c | 33 |
1 files changed, 29 insertions, 4 deletions
@@ -373,6 +373,7 @@ static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write) return false; } +/* Called from RCU critical section */ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr, hwaddr *xlat, hwaddr *plen, bool is_write) @@ -381,7 +382,6 @@ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr, MemoryRegionSection *section; MemoryRegion *mr; - rcu_read_lock(); for (;;) { AddressSpaceDispatch *d = atomic_rcu_read(&as->dispatch); section = address_space_translate_internal(d, addr, &addr, plen, true); @@ -409,7 +409,6 @@ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr, } *xlat = addr; - rcu_read_unlock(); return mr; } @@ -2329,6 +2328,7 @@ MemTxResult address_space_rw(AddressSpace *as, hwaddr addr, MemTxAttrs attrs, MemoryRegion *mr; MemTxResult result = MEMTX_OK; + rcu_read_lock(); while (len > 0) { l = len; mr = address_space_translate(as, addr, &addr1, &l, is_write); @@ -2415,6 +2415,7 @@ MemTxResult address_space_rw(AddressSpace *as, hwaddr addr, MemTxAttrs attrs, buf += l; addr += l; } + rcu_read_unlock(); return result; } @@ -2452,6 +2453,7 @@ static inline void cpu_physical_memory_write_rom_internal(AddressSpace *as, hwaddr addr1; MemoryRegion *mr; + rcu_read_lock(); while (len > 0) { l = len; mr = address_space_translate(as, addr, &addr1, &l, true); @@ -2477,6 +2479,7 @@ static inline void cpu_physical_memory_write_rom_internal(AddressSpace *as, buf += l; addr += l; } + rcu_read_unlock(); } /* used for ROM loading : can write in RAM and ROM */ @@ -2585,6 +2588,7 @@ bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_ MemoryRegion *mr; hwaddr l, xlat; + rcu_read_lock(); while (len > 0) { l = len; mr = address_space_translate(as, addr, &xlat, &l, is_write); @@ -2598,6 +2602,7 @@ bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_ len -= l; addr += l; } + rcu_read_unlock(); return true; } @@ -2624,9 +2629,12 @@ void *address_space_map(AddressSpace *as, } l = len; + rcu_read_lock(); mr = address_space_translate(as, addr, &xlat, &l, is_write); + if (!memory_access_is_direct(mr, is_write)) { if (atomic_xchg(&bounce.in_use, true)) { + rcu_read_unlock(); return NULL; } /* Avoid unbounded allocations */ @@ -2642,6 +2650,7 @@ void *address_space_map(AddressSpace *as, bounce.buffer, l); } + rcu_read_unlock(); *plen = l; return bounce.buffer; } @@ -2665,6 +2674,7 @@ void *address_space_map(AddressSpace *as, } memory_region_ref(mr); + rcu_read_unlock(); *plen = done; return qemu_ram_ptr_length(raddr + base, plen); } @@ -2728,6 +2738,7 @@ static inline uint32_t address_space_ldl_internal(AddressSpace *as, hwaddr addr, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, false); if (l < 4 || !memory_access_is_direct(mr, false)) { /* I/O case */ @@ -2762,6 +2773,7 @@ static inline uint32_t address_space_ldl_internal(AddressSpace *as, hwaddr addr, if (result) { *result = r; } + rcu_read_unlock(); return val; } @@ -2814,6 +2826,7 @@ static inline uint64_t address_space_ldq_internal(AddressSpace *as, hwaddr addr, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, false); if (l < 8 || !memory_access_is_direct(mr, false)) { @@ -2849,6 +2862,7 @@ static inline uint64_t address_space_ldq_internal(AddressSpace *as, hwaddr addr, if (result) { *result = r; } + rcu_read_unlock(); return val; } @@ -2921,6 +2935,7 @@ static inline uint32_t address_space_lduw_internal(AddressSpace *as, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, false); if (l < 2 || !memory_access_is_direct(mr, false)) { @@ -2956,6 +2971,7 @@ static inline uint32_t address_space_lduw_internal(AddressSpace *as, if (result) { *result = r; } + rcu_read_unlock(); return val; } @@ -3007,6 +3023,7 @@ void address_space_stl_notdirty(AddressSpace *as, hwaddr addr, uint32_t val, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, true); if (l < 4 || !memory_access_is_direct(mr, true)) { @@ -3029,6 +3046,7 @@ void address_space_stl_notdirty(AddressSpace *as, hwaddr addr, uint32_t val, if (result) { *result = r; } + rcu_read_unlock(); } void stl_phys_notdirty(AddressSpace *as, hwaddr addr, uint32_t val) @@ -3049,6 +3067,7 @@ static inline void address_space_stl_internal(AddressSpace *as, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, true); if (l < 4 || !memory_access_is_direct(mr, true)) { @@ -3083,6 +3102,7 @@ static inline void address_space_stl_internal(AddressSpace *as, if (result) { *result = r; } + rcu_read_unlock(); } void address_space_stl(AddressSpace *as, hwaddr addr, uint32_t val, @@ -3152,6 +3172,7 @@ static inline void address_space_stw_internal(AddressSpace *as, hwaddr addr1; MemTxResult r; + rcu_read_lock(); mr = address_space_translate(as, addr, &addr1, &l, true); if (l < 2 || !memory_access_is_direct(mr, true)) { #if defined(TARGET_WORDS_BIGENDIAN) @@ -3185,6 +3206,7 @@ static inline void address_space_stw_internal(AddressSpace *as, if (result) { *result = r; } + rcu_read_unlock(); } void address_space_stw(AddressSpace *as, hwaddr addr, uint32_t val, @@ -3322,12 +3344,15 @@ bool cpu_physical_memory_is_io(hwaddr phys_addr) { MemoryRegion*mr; hwaddr l = 1; + bool res; + rcu_read_lock(); mr = address_space_translate(&address_space_memory, phys_addr, &phys_addr, &l, false); - return !(memory_region_is_ram(mr) || - memory_region_is_romd(mr)); + res = !(memory_region_is_ram(mr) || memory_region_is_romd(mr)); + rcu_read_unlock(); + return res; } void qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque) |