diff options
Diffstat (limited to 'libbcache/bkey.c')
| -rw-r--r-- | libbcache/bkey.c | 1167 |
1 files changed, 0 insertions, 1167 deletions
diff --git a/libbcache/bkey.c b/libbcache/bkey.c deleted file mode 100644 index 374237e2..00000000 --- a/libbcache/bkey.c +++ /dev/null @@ -1,1167 +0,0 @@ - -#define pr_fmt(fmt) "bcache: %s() " fmt "\n", __func__ - -#include <linux/kernel.h> - -#include "bkey.h" -#include "bset.h" -#include "util.h" - -const struct bkey_format bch_bkey_format_current = BKEY_FORMAT_CURRENT; - -struct bkey __bkey_unpack_key(const struct bkey_format *, - const struct bkey_packed *); - -void bch_to_binary(char *out, const u64 *p, unsigned nr_bits) -{ - unsigned bit = high_bit_offset, done = 0; - - while (1) { - while (bit < 64) { - if (done && !(done % 8)) - *out++ = ' '; - *out++ = *p & (1ULL << (63 - bit)) ? '1' : '0'; - bit++; - done++; - if (done == nr_bits) { - *out++ = '\0'; - return; - } - } - - p = next_word(p); - bit = 0; - } -} - -#ifdef CONFIG_BCACHE_DEBUG - -static void bch_bkey_pack_verify(const struct bkey_packed *packed, - const struct bkey *unpacked, - const struct bkey_format *format) -{ - struct bkey tmp; - - BUG_ON(bkeyp_val_u64s(format, packed) != - bkey_val_u64s(unpacked)); - - BUG_ON(packed->u64s < bkeyp_key_u64s(format, packed)); - - tmp = __bkey_unpack_key(format, packed); - - if (memcmp(&tmp, unpacked, sizeof(struct bkey))) { - char buf1[160], buf2[160]; - char buf3[160], buf4[160]; - - bch_bkey_to_text(buf1, sizeof(buf1), unpacked); - bch_bkey_to_text(buf2, sizeof(buf2), &tmp); - bch_to_binary(buf3, (void *) unpacked, 80); - bch_to_binary(buf4, high_word(format, packed), 80); - - panic("keys differ: format u64s %u fields %u %u %u %u %u\n%s\n%s\n%s\n%s\n", - format->key_u64s, - format->bits_per_field[0], - format->bits_per_field[1], - format->bits_per_field[2], - format->bits_per_field[3], - format->bits_per_field[4], - buf1, buf2, buf3, buf4); - } -} - -#else -static inline void bch_bkey_pack_verify(const struct bkey_packed *packed, - const struct bkey *unpacked, - const struct bkey_format *format) {} -#endif - -int bch_bkey_to_text(char *buf, size_t size, const struct bkey *k) -{ - char *out = buf, *end = buf + size; - -#define p(...) (out += scnprintf(out, end - out, __VA_ARGS__)) - - p("u64s %u type %u %llu:%llu snap %u len %u ver %llu", - k->u64s, k->type, k->p.inode, k->p.offset, - k->p.snapshot, k->size, k->version.lo); - - BUG_ON(bkey_packed(k)); - - switch (k->type) { - case KEY_TYPE_DELETED: - p(" deleted"); - break; - case KEY_TYPE_DISCARD: - p(" discard"); - break; - case KEY_TYPE_ERROR: - p(" error"); - break; - case KEY_TYPE_COOKIE: - p(" cookie"); - break; - } -#undef p - - return out - buf; -} - -struct pack_state { - const struct bkey_format *format; - unsigned bits; /* bits remaining in current word */ - u64 w; /* current word */ - u64 *p; /* pointer to next word */ -}; - -__always_inline -static struct pack_state pack_state_init(const struct bkey_format *format, - struct bkey_packed *k) -{ - u64 *p = high_word(format, k); - - return (struct pack_state) { - .format = format, - .bits = 64 - high_bit_offset, - .w = 0, - .p = p, - }; -} - -__always_inline -static void pack_state_finish(struct pack_state *state, - struct bkey_packed *k) -{ - EBUG_ON(state->p < k->_data); - EBUG_ON(state->p >= k->_data + state->format->key_u64s); - - *state->p = state->w; -} - -struct unpack_state { - const struct bkey_format *format; - unsigned bits; /* bits remaining in current word */ - u64 w; /* current word */ - const u64 *p; /* pointer to next word */ -}; - -__always_inline -static struct unpack_state unpack_state_init(const struct bkey_format *format, - const struct bkey_packed *k) -{ - const u64 *p = high_word(format, k); - - return (struct unpack_state) { - .format = format, - .bits = 64 - high_bit_offset, - .w = *p << high_bit_offset, - .p = p, - }; -} - -__always_inline -static u64 get_inc_field(struct unpack_state *state, unsigned field) -{ - unsigned bits = state->format->bits_per_field[field]; - u64 v = 0, offset = le64_to_cpu(state->format->field_offset[field]); - - if (bits >= state->bits) { - v = state->w >> (64 - bits); - bits -= state->bits; - - state->p = next_word(state->p); - state->w = *state->p; - state->bits = 64; - } - - /* avoid shift by 64 if bits is 0 - bits is never 64 here: */ - v |= (state->w >> 1) >> (63 - bits); - state->w <<= bits; - state->bits -= bits; - - return v + offset; -} - -__always_inline -static bool set_inc_field(struct pack_state *state, unsigned field, u64 v) -{ - unsigned bits = state->format->bits_per_field[field]; - u64 offset = le64_to_cpu(state->format->field_offset[field]); - - if (v < offset) - return false; - - v -= offset; - - if (fls64(v) > bits) - return false; - - if (bits > state->bits) { - bits -= state->bits; - /* avoid shift by 64 if bits is 0 - bits is never 64 here: */ - state->w |= (v >> 1) >> (bits - 1); - - *state->p = state->w; - state->p = next_word(state->p); - state->w = 0; - state->bits = 64; - } - - state->bits -= bits; - state->w |= v << state->bits; - - return true; -} - -/* - * Note: does NOT set out->format (we don't know what it should be here!) - * - * Also: doesn't work on extents - it doesn't preserve the invariant that - * if k is packed bkey_start_pos(k) will successfully pack - */ -static bool bch_bkey_transform_key(const struct bkey_format *out_f, - struct bkey_packed *out, - const struct bkey_format *in_f, - const struct bkey_packed *in) -{ - struct pack_state out_s = pack_state_init(out_f, out); - struct unpack_state in_s = unpack_state_init(in_f, in); - unsigned i; - - out->_data[0] = 0; - - for (i = 0; i < BKEY_NR_FIELDS; i++) - if (!set_inc_field(&out_s, i, get_inc_field(&in_s, i))) - return false; - - /* Can't happen because the val would be too big to unpack: */ - EBUG_ON(in->u64s - in_f->key_u64s + out_f->key_u64s > U8_MAX); - - pack_state_finish(&out_s, out); - out->u64s = out_f->key_u64s + in->u64s - in_f->key_u64s; - out->needs_whiteout = in->needs_whiteout; - out->type = in->type; - - return true; -} - -bool bch_bkey_transform(const struct bkey_format *out_f, - struct bkey_packed *out, - const struct bkey_format *in_f, - const struct bkey_packed *in) -{ - if (!bch_bkey_transform_key(out_f, out, in_f, in)) - return false; - - memcpy_u64s((u64 *) out + out_f->key_u64s, - (u64 *) in + in_f->key_u64s, - (in->u64s - in_f->key_u64s)); - return true; -} - -#define bkey_fields() \ - x(BKEY_FIELD_INODE, p.inode) \ - x(BKEY_FIELD_OFFSET, p.offset) \ - x(BKEY_FIELD_SNAPSHOT, p.snapshot) \ - x(BKEY_FIELD_SIZE, size) \ - x(BKEY_FIELD_VERSION_HI, version.hi) \ - x(BKEY_FIELD_VERSION_LO, version.lo) - -struct bkey __bkey_unpack_key(const struct bkey_format *format, - const struct bkey_packed *in) -{ - struct unpack_state state = unpack_state_init(format, in); - struct bkey out; - - EBUG_ON(format->nr_fields != BKEY_NR_FIELDS); - EBUG_ON(in->u64s < format->key_u64s); - EBUG_ON(in->format != KEY_FORMAT_LOCAL_BTREE); - EBUG_ON(in->u64s - format->key_u64s + BKEY_U64s > U8_MAX); - - out.u64s = BKEY_U64s + in->u64s - format->key_u64s; - out.format = KEY_FORMAT_CURRENT; - out.needs_whiteout = in->needs_whiteout; - out.type = in->type; - out.pad[0] = 0; - -#define x(id, field) out.field = get_inc_field(&state, id); - bkey_fields() -#undef x - - return out; -} - -#ifndef HAVE_BCACHE_COMPILED_UNPACK -struct bpos __bkey_unpack_pos(const struct bkey_format *format, - const struct bkey_packed *in) -{ - struct unpack_state state = unpack_state_init(format, in); - struct bpos out; - - EBUG_ON(format->nr_fields != BKEY_NR_FIELDS); - EBUG_ON(in->u64s < format->key_u64s); - EBUG_ON(in->format != KEY_FORMAT_LOCAL_BTREE); - - out.inode = get_inc_field(&state, BKEY_FIELD_INODE); - out.offset = get_inc_field(&state, BKEY_FIELD_OFFSET); - out.snapshot = get_inc_field(&state, BKEY_FIELD_SNAPSHOT); - - return out; -} -#endif - -/** - * bkey_pack_key -- pack just the key, not the value - */ -bool bkey_pack_key(struct bkey_packed *out, const struct bkey *in, - const struct bkey_format *format) -{ - struct pack_state state = pack_state_init(format, out); - - EBUG_ON((void *) in == (void *) out); - EBUG_ON(format->nr_fields != BKEY_NR_FIELDS); - EBUG_ON(in->format != KEY_FORMAT_CURRENT); - - out->_data[0] = 0; - -#define x(id, field) if (!set_inc_field(&state, id, in->field)) return false; - bkey_fields() -#undef x - - /* - * Extents - we have to guarantee that if an extent is packed, a trimmed - * version will also pack: - */ - if (bkey_start_offset(in) < format->field_offset[BKEY_FIELD_OFFSET]) - return false; - - pack_state_finish(&state, out); - out->u64s = format->key_u64s + in->u64s - BKEY_U64s; - out->format = KEY_FORMAT_LOCAL_BTREE; - out->needs_whiteout = in->needs_whiteout; - out->type = in->type; - - bch_bkey_pack_verify(out, in, format); - return true; -} - -/** - * bkey_unpack -- unpack the key and the value - */ -void bkey_unpack(const struct btree *b, struct bkey_i *dst, - const struct bkey_packed *src) -{ - dst->k = bkey_unpack_key(b, src); - - memcpy_u64s(&dst->v, - bkeyp_val(&b->format, src), - bkeyp_val_u64s(&b->format, src)); -} - -/** - * bkey_pack -- pack the key and the value - */ -bool bkey_pack(struct bkey_packed *out, const struct bkey_i *in, - const struct bkey_format *format) -{ - struct bkey_packed tmp; - - if (!bkey_pack_key(&tmp, &in->k, format)) - return false; - - memmove_u64s((u64 *) out + format->key_u64s, - &in->v, - bkey_val_u64s(&in->k)); - memcpy_u64s(out, &tmp, format->key_u64s); - - return true; -} - -__always_inline -static bool set_inc_field_lossy(struct pack_state *state, unsigned field, u64 v) -{ - unsigned bits = state->format->bits_per_field[field]; - u64 offset = le64_to_cpu(state->format->field_offset[field]); - bool ret = true; - - EBUG_ON(v < offset); - v -= offset; - - if (fls64(v) > bits) { - v = ~(~0ULL << bits); - ret = false; - } - - if (bits > state->bits) { - bits -= state->bits; - state->w |= (v >> 1) >> (bits - 1); - - *state->p = state->w; - state->p = next_word(state->p); - state->w = 0; - state->bits = 64; - } - - state->bits -= bits; - state->w |= v << state->bits; - - return ret; -} - -#ifdef CONFIG_BCACHE_DEBUG -static bool bkey_packed_successor(struct bkey_packed *out, - const struct btree *b, - struct bkey_packed k) -{ - const struct bkey_format *f = &b->format; - unsigned nr_key_bits = b->nr_key_bits; - unsigned first_bit, offset; - u64 *p; - - EBUG_ON(b->nr_key_bits != bkey_format_key_bits(f)); - - if (!nr_key_bits) - return false; - - *out = k; - - first_bit = high_bit_offset + nr_key_bits - 1; - p = nth_word(high_word(f, out), first_bit >> 6); - offset = 63 - (first_bit & 63); - - while (nr_key_bits) { - unsigned bits = min(64 - offset, nr_key_bits); - u64 mask = (~0ULL >> (64 - bits)) << offset; - - if ((*p & mask) != mask) { - *p += 1ULL << offset; - EBUG_ON(bkey_cmp_packed(b, out, &k) <= 0); - return true; - } - - *p &= ~mask; - p = prev_word(p); - nr_key_bits -= bits; - offset = 0; - } - - return false; -} -#endif - -/* - * Returns a packed key that compares <= in - * - * This is used in bset_search_tree(), where we need a packed pos in order to be - * able to compare against the keys in the auxiliary search tree - and it's - * legal to use a packed pos that isn't equivalent to the original pos, - * _provided_ it compares <= to the original pos. - */ -enum bkey_pack_pos_ret bkey_pack_pos_lossy(struct bkey_packed *out, - struct bpos in, - const struct btree *b) -{ - const struct bkey_format *f = &b->format; - struct pack_state state = pack_state_init(f, out); -#ifdef CONFIG_BCACHE_DEBUG - struct bpos orig = in; -#endif - bool exact = true; - - out->_data[0] = 0; - - if (unlikely(in.snapshot < - le64_to_cpu(f->field_offset[BKEY_FIELD_SNAPSHOT]))) { - if (!in.offset-- && - !in.inode--) - return BKEY_PACK_POS_FAIL; - in.snapshot = KEY_SNAPSHOT_MAX; - exact = false; - } - - if (unlikely(in.offset < - le64_to_cpu(f->field_offset[BKEY_FIELD_OFFSET]))) { - if (!in.inode--) - return BKEY_PACK_POS_FAIL; - in.offset = KEY_OFFSET_MAX; - in.snapshot = KEY_SNAPSHOT_MAX; - exact = false; - } - - if (unlikely(in.inode < - le64_to_cpu(f->field_offset[BKEY_FIELD_INODE]))) - return BKEY_PACK_POS_FAIL; - - if (!set_inc_field_lossy(&state, BKEY_FIELD_INODE, in.inode)) { - in.offset = KEY_OFFSET_MAX; - in.snapshot = KEY_SNAPSHOT_MAX; - exact = false; - } - - if (!set_inc_field_lossy(&state, BKEY_FIELD_OFFSET, in.offset)) { - in.snapshot = KEY_SNAPSHOT_MAX; - exact = false; - } - - if (!set_inc_field_lossy(&state, BKEY_FIELD_SNAPSHOT, in.snapshot)) - exact = false; - - pack_state_finish(&state, out); - out->u64s = f->key_u64s; - out->format = KEY_FORMAT_LOCAL_BTREE; - out->type = KEY_TYPE_DELETED; - -#ifdef CONFIG_BCACHE_DEBUG - if (exact) { - BUG_ON(bkey_cmp_left_packed(b, out, &orig)); - } else { - struct bkey_packed successor; - - BUG_ON(bkey_cmp_left_packed(b, out, &orig) >= 0); - BUG_ON(bkey_packed_successor(&successor, b, *out) && - bkey_cmp_left_packed(b, &successor, &orig) < 0); - } -#endif - - return exact ? BKEY_PACK_POS_EXACT : BKEY_PACK_POS_SMALLER; -} - -void bch_bkey_format_init(struct bkey_format_state *s) -{ - unsigned i; - - for (i = 0; i < ARRAY_SIZE(s->field_min); i++) - s->field_min[i] = U64_MAX; - - for (i = 0; i < ARRAY_SIZE(s->field_max); i++) - s->field_max[i] = 0; - - /* Make sure we can store a size of 0: */ - s->field_min[BKEY_FIELD_SIZE] = 0; -} - -static void __bkey_format_add(struct bkey_format_state *s, - unsigned field, u64 v) -{ - s->field_min[field] = min(s->field_min[field], v); - s->field_max[field] = max(s->field_max[field], v); -} - -/* - * Changes @format so that @k can be successfully packed with @format - */ -void bch_bkey_format_add_key(struct bkey_format_state *s, const struct bkey *k) -{ -#define x(id, field) __bkey_format_add(s, id, k->field); - bkey_fields() -#undef x - __bkey_format_add(s, BKEY_FIELD_OFFSET, bkey_start_offset(k)); -} - -void bch_bkey_format_add_pos(struct bkey_format_state *s, struct bpos p) -{ - unsigned field = 0; - - __bkey_format_add(s, field++, p.inode); - __bkey_format_add(s, field++, p.offset); - __bkey_format_add(s, field++, p.snapshot); -} - -/* - * We don't want it to be possible for the packed format to represent fields - * bigger than a u64... that will cause confusion and issues (like with - * bkey_packed_successor()) - */ -static void set_format_field(struct bkey_format *f, enum bch_bkey_fields i, - unsigned bits, u64 offset) -{ - offset = bits == 64 ? 0 : min(offset, U64_MAX - ((1ULL << bits) - 1)); - - f->bits_per_field[i] = bits; - f->field_offset[i] = cpu_to_le64(offset); -} - -struct bkey_format bch_bkey_format_done(struct bkey_format_state *s) -{ - unsigned i, bits = KEY_PACKED_BITS_START; - struct bkey_format ret = { - .nr_fields = BKEY_NR_FIELDS, - }; - - for (i = 0; i < ARRAY_SIZE(s->field_min); i++) { - s->field_min[i] = min(s->field_min[i], s->field_max[i]); - - set_format_field(&ret, i, - fls64(s->field_max[i] - s->field_min[i]), - s->field_min[i]); - - bits += ret.bits_per_field[i]; - } - - /* allow for extent merging: */ - if (ret.bits_per_field[BKEY_FIELD_SIZE]) { - ret.bits_per_field[BKEY_FIELD_SIZE] += 4; - bits += 4; - } - - ret.key_u64s = DIV_ROUND_UP(bits, 64); - - /* if we have enough spare bits, round fields up to nearest byte */ - bits = ret.key_u64s * 64 - bits; - - for (i = 0; i < ARRAY_SIZE(ret.bits_per_field); i++) { - unsigned r = round_up(ret.bits_per_field[i], 8) - - ret.bits_per_field[i]; - - if (r <= bits) { - set_format_field(&ret, i, - ret.bits_per_field[i] + r, - le64_to_cpu(ret.field_offset[i])); - bits -= r; - } - } - - EBUG_ON(bch_bkey_format_validate(&ret)); - return ret; -} - -const char *bch_bkey_format_validate(struct bkey_format *f) -{ - unsigned i, bits = KEY_PACKED_BITS_START; - - if (f->nr_fields != BKEY_NR_FIELDS) - return "invalid format: incorrect number of fields"; - - for (i = 0; i < f->nr_fields; i++) { - u64 field_offset = le64_to_cpu(f->field_offset[i]); - - if (f->bits_per_field[i] > 64) - return "invalid format: field too large"; - - if (field_offset && - (f->bits_per_field[i] == 64 || - (field_offset + ((1ULL << f->bits_per_field[i]) - 1) < - field_offset))) - return "invalid format: offset + bits overflow"; - - bits += f->bits_per_field[i]; - } - - if (f->key_u64s != DIV_ROUND_UP(bits, 64)) - return "invalid format: incorrect key_u64s"; - - return NULL; -} - -/* - * Most significant differing bit - * Bits are indexed from 0 - return is [0, nr_key_bits) - */ -__pure -unsigned bkey_greatest_differing_bit(const struct btree *b, - const struct bkey_packed *l_k, - const struct bkey_packed *r_k) -{ - const u64 *l = high_word(&b->format, l_k); - const u64 *r = high_word(&b->format, r_k); - unsigned nr_key_bits = b->nr_key_bits; - unsigned word_bits = 64 - high_bit_offset; - u64 l_v, r_v; - - EBUG_ON(b->nr_key_bits != bkey_format_key_bits(&b->format)); - - /* for big endian, skip past header */ - l_v = *l & (~0ULL >> high_bit_offset); - r_v = *r & (~0ULL >> high_bit_offset); - - while (nr_key_bits) { - if (nr_key_bits < word_bits) { - l_v >>= word_bits - nr_key_bits; - r_v >>= word_bits - nr_key_bits; - nr_key_bits = 0; - } else { - nr_key_bits -= word_bits; - } - - if (l_v != r_v) - return fls64(l_v ^ r_v) - 1 + nr_key_bits; - - l = next_word(l); - r = next_word(r); - - l_v = *l; - r_v = *r; - word_bits = 64; - } - - return 0; -} - -/* - * First set bit - * Bits are indexed from 0 - return is [0, nr_key_bits) - */ -__pure -unsigned bkey_ffs(const struct btree *b, - const struct bkey_packed *k) -{ - const u64 *p = high_word(&b->format, k); - unsigned nr_key_bits = b->nr_key_bits; - unsigned ret = 0, offset; - - EBUG_ON(b->nr_key_bits != bkey_format_key_bits(&b->format)); - - offset = nr_key_bits; - while (offset > 64) { - p = next_word(p); - offset -= 64; - } - - offset = 64 - offset; - - while (nr_key_bits) { - unsigned bits = nr_key_bits + offset < 64 - ? nr_key_bits - : 64 - offset; - - u64 mask = (~0ULL >> (64 - bits)) << offset; - - if (*p & mask) - return ret + __ffs64(*p & mask) - offset; - - p = prev_word(p); - nr_key_bits -= bits; - ret += bits; - offset = 0; - } - - return 0; -} - -#ifdef CONFIG_X86_64 - -static inline int __bkey_cmp_bits(const u64 *l, const u64 *r, - unsigned nr_key_bits) -{ - long d0, d1, d2, d3; - int cmp; - - /* we shouldn't need asm for this, but gcc is being retarded: */ - - asm(".intel_syntax noprefix;" - "xor eax, eax;" - "xor edx, edx;" - "1:;" - "mov r8, [rdi];" - "mov r9, [rsi];" - "sub ecx, 64;" - "jl 2f;" - - "cmp r8, r9;" - "jnz 3f;" - - "lea rdi, [rdi - 8];" - "lea rsi, [rsi - 8];" - "jmp 1b;" - - "2:;" - "not ecx;" - "shr r8, 1;" - "shr r9, 1;" - "shr r8, cl;" - "shr r9, cl;" - "cmp r8, r9;" - - "3:\n" - "seta al;" - "setb dl;" - "sub eax, edx;" - ".att_syntax prefix;" - : "=&D" (d0), "=&S" (d1), "=&d" (d2), "=&c" (d3), "=&a" (cmp) - : "0" (l), "1" (r), "3" (nr_key_bits) - : "r8", "r9", "cc", "memory"); - - return cmp; -} - -#define I(_x) (*(out)++ = (_x)) -#define I1(i0) I(i0) -#define I2(i0, i1) (I1(i0), I(i1)) -#define I3(i0, i1, i2) (I2(i0, i1), I(i2)) -#define I4(i0, i1, i2, i3) (I3(i0, i1, i2), I(i3)) -#define I5(i0, i1, i2, i3, i4) (I4(i0, i1, i2, i3), I(i4)) - -static u8 *compile_bkey_field(const struct bkey_format *format, u8 *out, - enum bch_bkey_fields field, - unsigned dst_offset, unsigned dst_size, - bool *eax_zeroed) -{ - unsigned byte = format->key_u64s * sizeof(u64); - unsigned bits = format->bits_per_field[field]; - u64 offset = format->field_offset[field]; - unsigned i, bit_offset = 0; - unsigned shl, shr; - - if (!bits && !offset) { - if (!*eax_zeroed) { - /* xor eax, eax */ - I2(0x31, 0xc0); - } - - *eax_zeroed = true; - goto set_field; - } - - if (!bits) { - /* just return offset: */ - - switch (dst_size) { - case 8: - if (offset > S32_MAX) { - /* mov [rdi + dst_offset], offset */ - I3(0xc7, 0x47, dst_offset); - memcpy(out, &offset, 4); - out += 4; - - I3(0xc7, 0x47, dst_offset + 4); - memcpy(out, (void *) &offset + 4, 4); - out += 4; - } else { - /* mov [rdi + dst_offset], offset */ - /* sign extended */ - I4(0x48, 0xc7, 0x47, dst_offset); - memcpy(out, &offset, 4); - out += 4; - } - break; - case 4: - /* mov [rdi + dst_offset], offset */ - I3(0xc7, 0x47, dst_offset); - memcpy(out, &offset, 4); - out += 4; - break; - default: - BUG(); - } - - return out; - } - - for (i = 0; i <= field; i++) - bit_offset += format->bits_per_field[i]; - - byte -= DIV_ROUND_UP(bit_offset, 8); - bit_offset = round_up(bit_offset, 8) - bit_offset; - - *eax_zeroed = false; - - if (bit_offset == 0 && bits == 8) { - /* movzx eax, BYTE PTR [rsi + imm8] */ - I4(0x0f, 0xb6, 0x46, byte); - } else if (bit_offset == 0 && bits == 16) { - /* movzx eax, WORD PTR [rsi + imm8] */ - I4(0x0f, 0xb7, 0x46, byte); - } else if (bit_offset + bits <= 32) { - /* mov eax, [rsi + imm8] */ - I3(0x8b, 0x46, byte); - - if (bit_offset) { - /* shr eax, imm8 */ - I3(0xc1, 0xe8, bit_offset); - } - - if (bit_offset + bits < 32) { - unsigned mask = ~0U >> (32 - bits); - - /* and eax, imm32 */ - I1(0x25); - memcpy(out, &mask, 4); - out += 4; - } - } else if (bit_offset + bits <= 64) { - /* mov rax, [rsi + imm8] */ - I4(0x48, 0x8b, 0x46, byte); - - shl = 64 - bit_offset - bits; - shr = bit_offset + shl; - - if (shl) { - /* shl rax, imm8 */ - I4(0x48, 0xc1, 0xe0, shl); - } - - if (shr) { - /* shr rax, imm8 */ - I4(0x48, 0xc1, 0xe8, shr); - } - } else { - /* mov rax, [rsi + byte] */ - I4(0x48, 0x8b, 0x46, byte); - - /* mov edx, [rsi + byte + 8] */ - I3(0x8b, 0x56, byte + 8); - - /* bits from next word: */ - shr = bit_offset + bits - 64; - BUG_ON(shr > bit_offset); - - /* shr rax, bit_offset */ - I4(0x48, 0xc1, 0xe8, shr); - - /* shl rdx, imm8 */ - I4(0x48, 0xc1, 0xe2, 64 - shr); - - /* or rax, rdx */ - I3(0x48, 0x09, 0xd0); - - shr = bit_offset - shr; - - if (shr) { - /* shr rax, imm8 */ - I4(0x48, 0xc1, 0xe8, shr); - } - } - - /* rax += offset: */ - if (offset > S32_MAX) { - /* mov rdx, imm64 */ - I2(0x48, 0xba); - memcpy(out, &offset, 8); - out += 8; - /* add %rdx, %rax */ - I3(0x48, 0x01, 0xd0); - } else if (offset + (~0ULL >> (64 - bits)) > U32_MAX) { - /* add rax, imm32 */ - I2(0x48, 0x05); - memcpy(out, &offset, 4); - out += 4; - } else if (offset) { - /* add eax, imm32 */ - I1(0x05); - memcpy(out, &offset, 4); - out += 4; - } -set_field: - switch (dst_size) { - case 8: - /* mov [rdi + dst_offset], rax */ - I4(0x48, 0x89, 0x47, dst_offset); - break; - case 4: - /* mov [rdi + dst_offset], eax */ - I3(0x89, 0x47, dst_offset); - break; - default: - BUG(); - } - - return out; -} - -int bch_compile_bkey_format(const struct bkey_format *format, void *_out) -{ - bool eax_zeroed = false; - u8 *out = _out; - - /* - * rdi: dst - unpacked key - * rsi: src - packed key - */ - - /* k->u64s, k->format, k->type */ - - /* mov eax, [rsi] */ - I2(0x8b, 0x06); - - /* add eax, BKEY_U64s - format->key_u64s */ - I5(0x05, BKEY_U64s - format->key_u64s, KEY_FORMAT_CURRENT, 0, 0); - - /* and eax, imm32: mask out k->pad: */ - I5(0x25, 0xff, 0xff, 0xff, 0); - - /* mov [rdi], eax */ - I2(0x89, 0x07); - -#define x(id, field) \ - out = compile_bkey_field(format, out, id, \ - offsetof(struct bkey, field), \ - sizeof(((struct bkey *) NULL)->field), \ - &eax_zeroed); - bkey_fields() -#undef x - - /* retq */ - I1(0xc3); - - return (void *) out - _out; -} - -#else -static inline int __bkey_cmp_bits(const u64 *l, const u64 *r, - unsigned nr_key_bits) -{ - u64 l_v, r_v; - - if (!nr_key_bits) - return 0; - - /* for big endian, skip past header */ - nr_key_bits += high_bit_offset; - l_v = *l & (~0ULL >> high_bit_offset); - r_v = *r & (~0ULL >> high_bit_offset); - - while (1) { - if (nr_key_bits < 64) { - l_v >>= 64 - nr_key_bits; - r_v >>= 64 - nr_key_bits; - nr_key_bits = 0; - } else { - nr_key_bits -= 64; - } - - if (l_v != r_v) - return l_v < r_v ? -1 : 1; - - if (!nr_key_bits) - return 0; - - l = next_word(l); - r = next_word(r); - - l_v = *l; - r_v = *r; - } -} -#endif - -__pure -int __bkey_cmp_packed_format_checked(const struct bkey_packed *l, - const struct bkey_packed *r, - const struct btree *b) -{ - const struct bkey_format *f = &b->format; - int ret; - - EBUG_ON(!bkey_packed(l) || !bkey_packed(r)); - EBUG_ON(b->nr_key_bits != bkey_format_key_bits(f)); - - ret = __bkey_cmp_bits(high_word(f, l), - high_word(f, r), - b->nr_key_bits); - - EBUG_ON(ret != bkey_cmp(bkey_unpack_key_format_checked(b, l).p, - bkey_unpack_key_format_checked(b, r).p)); - return ret; -} - -__pure __flatten -int __bkey_cmp_left_packed_format_checked(const struct btree *b, - const struct bkey_packed *l, - const struct bpos *r) -{ - return bkey_cmp(bkey_unpack_pos_format_checked(b, l), *r); -} - -__pure __flatten -int __bkey_cmp_packed(const struct bkey_packed *l, - const struct bkey_packed *r, - const struct btree *b) -{ - int packed = bkey_lr_packed(l, r); - - if (likely(packed == BKEY_PACKED_BOTH)) - return __bkey_cmp_packed_format_checked(l, r, b); - - switch (packed) { - case BKEY_PACKED_NONE: - return bkey_cmp(((struct bkey *) l)->p, - ((struct bkey *) r)->p); - case BKEY_PACKED_LEFT: - return __bkey_cmp_left_packed_format_checked(b, - (struct bkey_packed *) l, - &((struct bkey *) r)->p); - case BKEY_PACKED_RIGHT: - return -__bkey_cmp_left_packed_format_checked(b, - (struct bkey_packed *) r, - &((struct bkey *) l)->p); - default: - unreachable(); - } -} - -__pure __flatten -int bkey_cmp_left_packed(const struct btree *b, - const struct bkey_packed *l, const struct bpos *r) -{ - const struct bkey *l_unpacked; - - return unlikely(l_unpacked = packed_to_bkey_c(l)) - ? bkey_cmp(l_unpacked->p, *r) - : __bkey_cmp_left_packed_format_checked(b, l, r); -} - -void bch_bpos_swab(struct bpos *p) -{ - u8 *l = (u8 *) p; - u8 *h = ((u8 *) &p[1]) - 1; - - while (l < h) { - swap(*l, *h); - l++; - --h; - } -} - -void bch_bkey_swab_key(const struct bkey_format *_f, struct bkey_packed *k) -{ - const struct bkey_format *f = bkey_packed(k) ? _f : &bch_bkey_format_current; - u8 *l = k->key_start; - u8 *h = (u8 *) (k->_data + f->key_u64s) - 1; - - while (l < h) { - swap(*l, *h); - l++; - --h; - } -} - -#ifdef CONFIG_BCACHE_DEBUG -void bkey_pack_test(void) -{ - struct bkey t = KEY(4134ULL, 1250629070527416633ULL, 0); - struct bkey_packed p; - - struct bkey_format test_format = { - .key_u64s = 2, - .nr_fields = BKEY_NR_FIELDS, - .bits_per_field = { - 13, - 64, - }, - }; - - struct unpack_state in_s = - unpack_state_init(&bch_bkey_format_current, (void *) &t); - struct pack_state out_s = pack_state_init(&test_format, &p); - unsigned i; - - for (i = 0; i < out_s.format->nr_fields; i++) { - u64 a, v = get_inc_field(&in_s, i); - - switch (i) { -#define x(id, field) case id: a = t.field; break; - bkey_fields() -#undef x - default: - BUG(); - } - - if (a != v) - panic("got %llu actual %llu i %u\n", v, a, i); - - if (!set_inc_field(&out_s, i, v)) - panic("failed at %u\n", i); - } - - BUG_ON(!bkey_pack_key(&p, &t, &test_format)); -} -#endif |