diff options
Diffstat (limited to 'accel/tcg/tb-maint.c')
| -rw-r--r-- | accel/tcg/tb-maint.c | 120 |
1 files changed, 116 insertions, 4 deletions
diff --git a/accel/tcg/tb-maint.c b/accel/tcg/tb-maint.c index 20e86c813d..d32e5f80c8 100644 --- a/accel/tcg/tb-maint.c +++ b/accel/tcg/tb-maint.c @@ -127,6 +127,111 @@ static PageForEachNext foreach_tb_next(PageForEachNext tb, } #else +/* + * In system mode we want L1_MAP to be based on ram offsets. + */ +#if HOST_LONG_BITS < TARGET_PHYS_ADDR_SPACE_BITS +# define L1_MAP_ADDR_SPACE_BITS HOST_LONG_BITS +#else +# define L1_MAP_ADDR_SPACE_BITS TARGET_PHYS_ADDR_SPACE_BITS +#endif + +/* Size of the L2 (and L3, etc) page tables. */ +#define V_L2_BITS 10 +#define V_L2_SIZE (1 << V_L2_BITS) + +/* + * L1 Mapping properties + */ +static int v_l1_size; +static int v_l1_shift; +static int v_l2_levels; + +/* + * The bottom level has pointers to PageDesc, and is indexed by + * anything from 4 to (V_L2_BITS + 3) bits, depending on target page size. + */ +#define V_L1_MIN_BITS 4 +#define V_L1_MAX_BITS (V_L2_BITS + 3) +#define V_L1_MAX_SIZE (1 << V_L1_MAX_BITS) + +static void *l1_map[V_L1_MAX_SIZE]; + +void page_table_config_init(void) +{ + uint32_t v_l1_bits; + + assert(TARGET_PAGE_BITS); + /* The bits remaining after N lower levels of page tables. */ + v_l1_bits = (L1_MAP_ADDR_SPACE_BITS - TARGET_PAGE_BITS) % V_L2_BITS; + if (v_l1_bits < V_L1_MIN_BITS) { + v_l1_bits += V_L2_BITS; + } + + v_l1_size = 1 << v_l1_bits; + v_l1_shift = L1_MAP_ADDR_SPACE_BITS - TARGET_PAGE_BITS - v_l1_bits; + v_l2_levels = v_l1_shift / V_L2_BITS - 1; + + assert(v_l1_bits <= V_L1_MAX_BITS); + assert(v_l1_shift % V_L2_BITS == 0); + assert(v_l2_levels >= 0); +} + +PageDesc *page_find_alloc(tb_page_addr_t index, bool alloc) +{ + PageDesc *pd; + void **lp; + int i; + + /* Level 1. Always allocated. */ + lp = l1_map + ((index >> v_l1_shift) & (v_l1_size - 1)); + + /* Level 2..N-1. */ + for (i = v_l2_levels; i > 0; i--) { + void **p = qatomic_rcu_read(lp); + + if (p == NULL) { + void *existing; + + if (!alloc) { + return NULL; + } + p = g_new0(void *, V_L2_SIZE); + existing = qatomic_cmpxchg(lp, NULL, p); + if (unlikely(existing)) { + g_free(p); + p = existing; + } + } + + lp = p + ((index >> (i * V_L2_BITS)) & (V_L2_SIZE - 1)); + } + + pd = qatomic_rcu_read(lp); + if (pd == NULL) { + void *existing; + + if (!alloc) { + return NULL; + } + + pd = g_new0(PageDesc, V_L2_SIZE); + for (int i = 0; i < V_L2_SIZE; i++) { + qemu_spin_init(&pd[i].lock); + } + + existing = qatomic_cmpxchg(lp, NULL, pd); + if (unlikely(existing)) { + for (int i = 0; i < V_L2_SIZE; i++) { + qemu_spin_destroy(&pd[i].lock); + } + g_free(pd); + pd = existing; + } + } + + return pd + (index & (V_L2_SIZE - 1)); +} /* Set to NULL all the 'first_tb' fields in all PageDescs. */ static void tb_remove_all_1(int level, void **lp) @@ -420,6 +525,17 @@ static void tb_phys_invalidate__locked(TranslationBlock *tb) qemu_thread_jit_execute(); } +#ifdef CONFIG_USER_ONLY +static inline void page_lock_pair(PageDesc **ret_p1, tb_page_addr_t phys1, + PageDesc **ret_p2, tb_page_addr_t phys2, + bool alloc) +{ + *ret_p1 = NULL; + *ret_p2 = NULL; +} +static inline void page_lock_tb(const TranslationBlock *tb) { } +static inline void page_unlock_tb(const TranslationBlock *tb) { } +#else static void page_lock_pair(PageDesc **ret_p1, tb_page_addr_t phys1, PageDesc **ret_p2, tb_page_addr_t phys2, bool alloc) { @@ -460,10 +576,6 @@ static void page_lock_pair(PageDesc **ret_p1, tb_page_addr_t phys1, } } -#ifdef CONFIG_USER_ONLY -static inline void page_lock_tb(const TranslationBlock *tb) { } -static inline void page_unlock_tb(const TranslationBlock *tb) { } -#else /* lock the page(s) of a TB in the correct acquisition order */ static void page_lock_tb(const TranslationBlock *tb) { |