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-rw-r--r--lib/Kconfig2
-rw-r--r--lib/asn1_decoder.c16
-rw-r--r--lib/assoc_array.c4
-rw-r--r--lib/dma-debug.c4
-rw-r--r--lib/dump_stack.c7
-rw-r--r--lib/iov_iter.c24
-rw-r--r--lib/klist.c6
-rw-r--r--lib/libcrc32c.c1
-rw-r--r--lib/lz4/lz4defs.h21
-rw-r--r--lib/mpi/mpicoder.c60
-rw-r--r--lib/radix-tree.c12
-rw-r--r--lib/string_helpers.c63
-rw-r--r--lib/test-string_helpers.c67
-rw-r--r--lib/ucs2_string.c62
14 files changed, 232 insertions, 117 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index f0df318104e7..1a48744253d7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -210,9 +210,11 @@ config RANDOM32_SELFTEST
# compression support is select'ed if needed
#
config 842_COMPRESS
+ select CRC32
tristate
config 842_DECOMPRESS
+ select CRC32
tristate
config ZLIB_INFLATE
diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c
index 2b3f46c049d4..554522934c44 100644
--- a/lib/asn1_decoder.c
+++ b/lib/asn1_decoder.c
@@ -74,7 +74,7 @@ next_tag:
/* Extract a tag from the data */
tag = data[dp++];
- if (tag == 0) {
+ if (tag == ASN1_EOC) {
/* It appears to be an EOC. */
if (data[dp++] != 0)
goto invalid_eoc;
@@ -96,10 +96,8 @@ next_tag:
/* Extract the length */
len = data[dp++];
- if (len <= 0x7f) {
- dp += len;
- goto next_tag;
- }
+ if (len <= 0x7f)
+ goto check_length;
if (unlikely(len == ASN1_INDEFINITE_LENGTH)) {
/* Indefinite length */
@@ -110,14 +108,18 @@ next_tag:
}
n = len - 0x80;
- if (unlikely(n > sizeof(size_t) - 1))
+ if (unlikely(n > sizeof(len) - 1))
goto length_too_long;
if (unlikely(n > datalen - dp))
goto data_overrun_error;
- for (len = 0; n > 0; n--) {
+ len = 0;
+ for (; n > 0; n--) {
len <<= 8;
len |= data[dp++];
}
+check_length:
+ if (len > datalen - dp)
+ goto data_overrun_error;
dp += len;
goto next_tag;
diff --git a/lib/assoc_array.c b/lib/assoc_array.c
index 03dd576e6773..59fd7c0b119c 100644
--- a/lib/assoc_array.c
+++ b/lib/assoc_array.c
@@ -524,7 +524,9 @@ static bool assoc_array_insert_into_terminal_node(struct assoc_array_edit *edit,
free_slot = i;
continue;
}
- if (ops->compare_object(assoc_array_ptr_to_leaf(ptr), index_key)) {
+ if (assoc_array_ptr_is_leaf(ptr) &&
+ ops->compare_object(assoc_array_ptr_to_leaf(ptr),
+ index_key)) {
pr_devel("replace in slot %d\n", i);
edit->leaf_p = &node->slots[i];
edit->dead_leaf = node->slots[i];
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index d34bd24c2c84..51a76af25c66 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -657,9 +657,9 @@ static struct dma_debug_entry *dma_entry_alloc(void)
spin_lock_irqsave(&free_entries_lock, flags);
if (list_empty(&free_entries)) {
- pr_err("DMA-API: debugging out of memory - disabling\n");
global_disable = true;
spin_unlock_irqrestore(&free_entries_lock, flags);
+ pr_err("DMA-API: debugging out of memory - disabling\n");
return NULL;
}
@@ -1181,7 +1181,7 @@ static inline bool overlap(void *addr, unsigned long len, void *start, void *end
static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len)
{
- if (overlap(addr, len, _text, _etext) ||
+ if (overlap(addr, len, _stext, _etext) ||
overlap(addr, len, __start_rodata, __end_rodata))
err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len);
}
diff --git a/lib/dump_stack.c b/lib/dump_stack.c
index 6745c6230db3..c30d07e99dba 100644
--- a/lib/dump_stack.c
+++ b/lib/dump_stack.c
@@ -25,6 +25,7 @@ static atomic_t dump_lock = ATOMIC_INIT(-1);
asmlinkage __visible void dump_stack(void)
{
+ unsigned long flags;
int was_locked;
int old;
int cpu;
@@ -33,9 +34,8 @@ asmlinkage __visible void dump_stack(void)
* Permit this cpu to perform nested stack dumps while serialising
* against other CPUs
*/
- preempt_disable();
-
retry:
+ local_irq_save(flags);
cpu = smp_processor_id();
old = atomic_cmpxchg(&dump_lock, -1, cpu);
if (old == -1) {
@@ -43,6 +43,7 @@ retry:
} else if (old == cpu) {
was_locked = 1;
} else {
+ local_irq_restore(flags);
cpu_relax();
goto retry;
}
@@ -52,7 +53,7 @@ retry:
if (!was_locked)
atomic_set(&dump_lock, -1);
- preempt_enable();
+ local_irq_restore(flags);
}
#else
asmlinkage __visible void dump_stack(void)
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 75232ad0a5e7..daca582a8ed0 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -298,33 +298,13 @@ done:
}
/*
- * Fault in the first iovec of the given iov_iter, to a maximum length
- * of bytes. Returns 0 on success, or non-zero if the memory could not be
- * accessed (ie. because it is an invalid address).
- *
- * writev-intensive code may want this to prefault several iovecs -- that
- * would be possible (callers must not rely on the fact that _only_ the
- * first iovec will be faulted with the current implementation).
- */
-int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
-{
- if (!(i->type & (ITER_BVEC|ITER_KVEC))) {
- char __user *buf = i->iov->iov_base + i->iov_offset;
- bytes = min(bytes, i->iov->iov_len - i->iov_offset);
- return fault_in_pages_readable(buf, bytes);
- }
- return 0;
-}
-EXPORT_SYMBOL(iov_iter_fault_in_readable);
-
-/*
* Fault in one or more iovecs of the given iov_iter, to a maximum length of
* bytes. For each iovec, fault in each page that constitutes the iovec.
*
* Return 0 on success, or non-zero if the memory could not be accessed (i.e.
* because it is an invalid address).
*/
-int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes)
+int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
{
size_t skip = i->iov_offset;
const struct iovec *iov;
@@ -341,7 +321,7 @@ int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes)
}
return 0;
}
-EXPORT_SYMBOL(iov_iter_fault_in_multipages_readable);
+EXPORT_SYMBOL(iov_iter_fault_in_readable);
void iov_iter_init(struct iov_iter *i, int direction,
const struct iovec *iov, unsigned long nr_segs,
diff --git a/lib/klist.c b/lib/klist.c
index d74cf7a29afd..0507fa5d84c5 100644
--- a/lib/klist.c
+++ b/lib/klist.c
@@ -282,9 +282,9 @@ void klist_iter_init_node(struct klist *k, struct klist_iter *i,
struct klist_node *n)
{
i->i_klist = k;
- i->i_cur = n;
- if (n)
- kref_get(&n->n_ref);
+ i->i_cur = NULL;
+ if (n && kref_get_unless_zero(&n->n_ref))
+ i->i_cur = n;
}
EXPORT_SYMBOL_GPL(klist_iter_init_node);
diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c
index 6a08ce7d6adc..acf9da449f81 100644
--- a/lib/libcrc32c.c
+++ b/lib/libcrc32c.c
@@ -74,3 +74,4 @@ module_exit(libcrc32c_mod_fini);
MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations");
MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: crc32c");
diff --git a/lib/lz4/lz4defs.h b/lib/lz4/lz4defs.h
index abcecdc2d0f2..0710a62ad2f6 100644
--- a/lib/lz4/lz4defs.h
+++ b/lib/lz4/lz4defs.h
@@ -11,8 +11,7 @@
/*
* Detects 64 bits mode
*/
-#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) \
- || defined(__ppc64__) || defined(__LP64__))
+#if defined(CONFIG_64BIT)
#define LZ4_ARCH64 1
#else
#define LZ4_ARCH64 0
@@ -35,6 +34,10 @@ typedef struct _U64_S { u64 v; } U64_S;
#define PUT4(s, d) (A32(d) = A32(s))
#define PUT8(s, d) (A64(d) = A64(s))
+
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
+ (d = s - A16(p))
+
#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
do { \
A16(p) = v; \
@@ -51,10 +54,13 @@ typedef struct _U64_S { u64 v; } U64_S;
#define PUT8(s, d) \
put_unaligned(get_unaligned((const u64 *) s), (u64 *) d)
-#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
- do { \
- put_unaligned(v, (u16 *)(p)); \
- p += 2; \
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
+ (d = s - get_unaligned_le16(p))
+
+#define LZ4_WRITE_LITTLEENDIAN_16(p, v) \
+ do { \
+ put_unaligned_le16(v, (u16 *)(p)); \
+ p += 2; \
} while (0)
#endif
@@ -140,9 +146,6 @@ typedef struct _U64_S { u64 v; } U64_S;
#endif
-#define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
- (d = s - get_unaligned_le16(p))
-
#define LZ4_WILDCOPY(s, d, e) \
do { \
LZ4_COPYPACKET(s, d); \
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 3db76b8c1115..e37dbf53e226 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -128,6 +128,23 @@ leave:
}
EXPORT_SYMBOL_GPL(mpi_read_from_buffer);
+static int count_lzeros(MPI a)
+{
+ mpi_limb_t alimb;
+ int i, lzeros = 0;
+
+ for (i = a->nlimbs - 1; i >= 0; i--) {
+ alimb = a->d[i];
+ if (alimb == 0) {
+ lzeros += sizeof(mpi_limb_t);
+ } else {
+ lzeros += count_leading_zeros(alimb) / 8;
+ break;
+ }
+ }
+ return lzeros;
+}
+
/**
* mpi_read_buffer() - read MPI to a bufer provided by user (msb first)
*
@@ -146,7 +163,7 @@ int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
uint8_t *p;
mpi_limb_t alimb;
unsigned int n = mpi_get_size(a);
- int i, lzeros = 0;
+ int i, lzeros;
if (buf_len < n || !buf || !nbytes)
return -EINVAL;
@@ -154,14 +171,7 @@ int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
if (sign)
*sign = a->sign;
- p = (void *)&a->d[a->nlimbs] - 1;
-
- for (i = a->nlimbs * sizeof(alimb) - 1; i >= 0; i--, p--) {
- if (!*p)
- lzeros++;
- else
- break;
- }
+ lzeros = count_lzeros(a);
p = buf;
*nbytes = n - lzeros;
@@ -343,7 +353,7 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
u8 *p, *p2;
mpi_limb_t alimb, alimb2;
unsigned int n = mpi_get_size(a);
- int i, x, y = 0, lzeros = 0, buf_len;
+ int i, x, y = 0, lzeros, buf_len;
if (!nbytes || *nbytes < n)
return -EINVAL;
@@ -351,20 +361,15 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
if (sign)
*sign = a->sign;
- p = (void *)&a->d[a->nlimbs] - 1;
-
- for (i = a->nlimbs * sizeof(alimb) - 1; i >= 0; i--, p--) {
- if (!*p)
- lzeros++;
- else
- break;
- }
+ lzeros = count_lzeros(a);
*nbytes = n - lzeros;
buf_len = sgl->length;
p2 = sg_virt(sgl);
- for (i = a->nlimbs - 1; i >= 0; i--) {
+ for (i = a->nlimbs - 1 - lzeros / BYTES_PER_MPI_LIMB,
+ lzeros %= BYTES_PER_MPI_LIMB;
+ i >= 0; i--) {
alimb = a->d[i];
p = (u8 *)&alimb2;
#if BYTES_PER_MPI_LIMB == 4
@@ -385,17 +390,12 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
#error please implement for this limb size.
#endif
if (lzeros > 0) {
- if (lzeros >= sizeof(alimb)) {
- p -= sizeof(alimb);
- continue;
- } else {
- mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
- mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
- + lzeros;
- *limb1 = *limb2;
- p -= lzeros;
- y = lzeros;
- }
+ mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
+ mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
+ + lzeros;
+ *limb1 = *limb2;
+ p -= lzeros;
+ y = lzeros;
lzeros -= sizeof(alimb);
}
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index fcf5d98574ce..6b79e9026e24 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -1019,9 +1019,13 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
return 0;
radix_tree_for_each_slot(slot, root, &iter, first_index) {
- results[ret] = indirect_to_ptr(rcu_dereference_raw(*slot));
+ results[ret] = rcu_dereference_raw(*slot);
if (!results[ret])
continue;
+ if (radix_tree_is_indirect_ptr(results[ret])) {
+ slot = radix_tree_iter_retry(&iter);
+ continue;
+ }
if (++ret == max_items)
break;
}
@@ -1098,9 +1102,13 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results,
return 0;
radix_tree_for_each_tagged(slot, root, &iter, first_index, tag) {
- results[ret] = indirect_to_ptr(rcu_dereference_raw(*slot));
+ results[ret] = rcu_dereference_raw(*slot);
if (!results[ret])
continue;
+ if (radix_tree_is_indirect_ptr(results[ret])) {
+ slot = radix_tree_iter_retry(&iter);
+ continue;
+ }
if (++ret == max_items)
break;
}
diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 5939f63d90cd..5c88204b6f1f 100644
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -43,50 +43,73 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units,
[STRING_UNITS_10] = 1000,
[STRING_UNITS_2] = 1024,
};
- int i, j;
- u32 remainder = 0, sf_cap, exp;
+ static const unsigned int rounding[] = { 500, 50, 5 };
+ int i = 0, j;
+ u32 remainder = 0, sf_cap;
char tmp[8];
const char *unit;
tmp[0] = '\0';
- i = 0;
- if (!size)
+
+ if (blk_size == 0)
+ size = 0;
+ if (size == 0)
goto out;
- while (blk_size >= divisor[units]) {
- remainder = do_div(blk_size, divisor[units]);
+ /* This is Napier's algorithm. Reduce the original block size to
+ *
+ * coefficient * divisor[units]^i
+ *
+ * we do the reduction so both coefficients are just under 32 bits so
+ * that multiplying them together won't overflow 64 bits and we keep
+ * as much precision as possible in the numbers.
+ *
+ * Note: it's safe to throw away the remainders here because all the
+ * precision is in the coefficients.
+ */
+ while (blk_size >> 32) {
+ do_div(blk_size, divisor[units]);
i++;
}
- exp = divisor[units] / (u32)blk_size;
- /*
- * size must be strictly greater than exp here to ensure that remainder
- * is greater than divisor[units] coming out of the if below.
- */
- if (size > exp) {
- remainder = do_div(size, divisor[units]);
- remainder *= blk_size;
+ while (size >> 32) {
+ do_div(size, divisor[units]);
i++;
- } else {
- remainder *= size;
}
+ /* now perform the actual multiplication keeping i as the sum of the
+ * two logarithms */
size *= blk_size;
- size += remainder / divisor[units];
- remainder %= divisor[units];
+ /* and logarithmically reduce it until it's just under the divisor */
while (size >= divisor[units]) {
remainder = do_div(size, divisor[units]);
i++;
}
+ /* work out in j how many digits of precision we need from the
+ * remainder */
sf_cap = size;
for (j = 0; sf_cap*10 < 1000; j++)
sf_cap *= 10;
- if (j) {
+ if (units == STRING_UNITS_2) {
+ /* express the remainder as a decimal. It's currently the
+ * numerator of a fraction whose denominator is
+ * divisor[units], which is 1 << 10 for STRING_UNITS_2 */
remainder *= 1000;
- remainder /= divisor[units];
+ remainder >>= 10;
+ }
+
+ /* add a 5 to the digit below what will be printed to ensure
+ * an arithmetical round up and carry it through to size */
+ remainder += rounding[j];
+ if (remainder >= 1000) {
+ remainder -= 1000;
+ size += 1;
+ }
+
+ if (j) {
snprintf(tmp, sizeof(tmp), ".%03u", remainder);
tmp[j+1] = '\0';
}
diff --git a/lib/test-string_helpers.c b/lib/test-string_helpers.c
index 98866a770770..25b5cbfb7615 100644
--- a/lib/test-string_helpers.c
+++ b/lib/test-string_helpers.c
@@ -327,36 +327,67 @@ out:
}
#define string_get_size_maxbuf 16
-#define test_string_get_size_one(size, blk_size, units, exp_result) \
+#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2) \
do { \
- BUILD_BUG_ON(sizeof(exp_result) >= string_get_size_maxbuf); \
- __test_string_get_size((size), (blk_size), (units), \
- (exp_result)); \
+ BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf); \
+ BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf); \
+ __test_string_get_size((size), (blk_size), (exp_result10), \
+ (exp_result2)); \
} while (0)
-static __init void __test_string_get_size(const u64 size, const u64 blk_size,
- const enum string_size_units units,
- const char *exp_result)
+static __init void test_string_get_size_check(const char *units,
+ const char *exp,
+ char *res,
+ const u64 size,
+ const u64 blk_size)
{
- char buf[string_get_size_maxbuf];
-
- string_get_size(size, blk_size, units, buf, sizeof(buf));
- if (!memcmp(buf, exp_result, strlen(exp_result) + 1))
+ if (!memcmp(res, exp, strlen(exp) + 1))
return;
- buf[sizeof(buf) - 1] = '\0';
- pr_warn("Test 'test_string_get_size_one' failed!\n");
- pr_warn("string_get_size(size = %llu, blk_size = %llu, units = %d\n",
+ res[string_get_size_maxbuf - 1] = '\0';
+
+ pr_warn("Test 'test_string_get_size' failed!\n");
+ pr_warn("string_get_size(size = %llu, blk_size = %llu, units = %s)\n",
size, blk_size, units);
- pr_warn("expected: '%s', got '%s'\n", exp_result, buf);
+ pr_warn("expected: '%s', got '%s'\n", exp, res);
+}
+
+static __init void __test_string_get_size(const u64 size, const u64 blk_size,
+ const char *exp_result10,
+ const char *exp_result2)
+{
+ char buf10[string_get_size_maxbuf];
+ char buf2[string_get_size_maxbuf];
+
+ string_get_size(size, blk_size, STRING_UNITS_10, buf10, sizeof(buf10));
+ string_get_size(size, blk_size, STRING_UNITS_2, buf2, sizeof(buf2));
+
+ test_string_get_size_check("STRING_UNITS_10", exp_result10, buf10,
+ size, blk_size);
+
+ test_string_get_size_check("STRING_UNITS_2", exp_result2, buf2,
+ size, blk_size);
}
static __init void test_string_get_size(void)
{
- test_string_get_size_one(16384, 512, STRING_UNITS_2, "8.00 MiB");
- test_string_get_size_one(8192, 4096, STRING_UNITS_10, "32.7 MB");
- test_string_get_size_one(1, 512, STRING_UNITS_10, "512 B");
+ /* small values */
+ test_string_get_size_one(0, 512, "0 B", "0 B");
+ test_string_get_size_one(1, 512, "512 B", "512 B");
+ test_string_get_size_one(1100, 1, "1.10 kB", "1.07 KiB");
+
+ /* normal values */
+ test_string_get_size_one(16384, 512, "8.39 MB", "8.00 MiB");
+ test_string_get_size_one(500118192, 512, "256 GB", "238 GiB");
+ test_string_get_size_one(8192, 4096, "33.6 MB", "32.0 MiB");
+
+ /* weird block sizes */
+ test_string_get_size_one(3000, 1900, "5.70 MB", "5.44 MiB");
+
+ /* huge values */
+ test_string_get_size_one(U64_MAX, 4096, "75.6 ZB", "64.0 ZiB");
+ test_string_get_size_one(4096, U64_MAX, "75.6 ZB", "64.0 ZiB");
}
static int __init test_string_helpers_init(void)
diff --git a/lib/ucs2_string.c b/lib/ucs2_string.c
index 6f500ef2301d..f0b323abb4c6 100644
--- a/lib/ucs2_string.c
+++ b/lib/ucs2_string.c
@@ -49,3 +49,65 @@ ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len)
}
}
EXPORT_SYMBOL(ucs2_strncmp);
+
+unsigned long
+ucs2_utf8size(const ucs2_char_t *src)
+{
+ unsigned long i;
+ unsigned long j = 0;
+
+ for (i = 0; i < ucs2_strlen(src); i++) {
+ u16 c = src[i];
+
+ if (c >= 0x800)
+ j += 3;
+ else if (c >= 0x80)
+ j += 2;
+ else
+ j += 1;
+ }
+
+ return j;
+}
+EXPORT_SYMBOL(ucs2_utf8size);
+
+/*
+ * copy at most maxlength bytes of whole utf8 characters to dest from the
+ * ucs2 string src.
+ *
+ * The return value is the number of characters copied, not including the
+ * final NUL character.
+ */
+unsigned long
+ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength)
+{
+ unsigned int i;
+ unsigned long j = 0;
+ unsigned long limit = ucs2_strnlen(src, maxlength);
+
+ for (i = 0; maxlength && i < limit; i++) {
+ u16 c = src[i];
+
+ if (c >= 0x800) {
+ if (maxlength < 3)
+ break;
+ maxlength -= 3;
+ dest[j++] = 0xe0 | (c & 0xf000) >> 12;
+ dest[j++] = 0x80 | (c & 0x0fc0) >> 6;
+ dest[j++] = 0x80 | (c & 0x003f);
+ } else if (c >= 0x80) {
+ if (maxlength < 2)
+ break;
+ maxlength -= 2;
+ dest[j++] = 0xc0 | (c & 0x7c0) >> 6;
+ dest[j++] = 0x80 | (c & 0x03f);
+ } else {
+ maxlength -= 1;
+ dest[j++] = c & 0x7f;
+ }
+ }
+ if (maxlength)
+ dest[j] = '\0';
+ return j;
+}
+EXPORT_SYMBOL(ucs2_as_utf8);