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-rw-r--r--lib/842/842.h2
-rw-r--r--lib/842/842_compress.c13
-rw-r--r--lib/842/842_decompress.c17
-rw-r--r--lib/Kconfig1
-rw-r--r--lib/Kconfig.debug1
-rw-r--r--lib/Makefile3
-rw-r--r--lib/devres.c2
-rw-r--r--lib/digsig.c7
-rw-r--r--lib/dma-debug.c2
-rw-r--r--lib/fault-inject.c2
-rw-r--r--lib/kobject.c12
-rw-r--r--lib/mpi/mpicoder.c199
-rw-r--r--lib/nmi_backtrace.c11
-rw-r--r--lib/once.c62
-rw-r--r--lib/random32.c37
-rw-r--r--lib/string.c89
16 files changed, 429 insertions, 31 deletions
diff --git a/lib/842/842.h b/lib/842/842.h
index 7c200030acf7..e0a122bc1cdb 100644
--- a/lib/842/842.h
+++ b/lib/842/842.h
@@ -76,6 +76,7 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/bitops.h>
+#include <linux/crc32.h>
#include <asm/unaligned.h>
#include <linux/sw842.h>
@@ -98,6 +99,7 @@
#define I2_BITS (8)
#define I4_BITS (9)
#define I8_BITS (8)
+#define CRC_BITS (32)
#define REPEAT_BITS_MAX (0x3f)
#define SHORT_DATA_BITS_MAX (0x7)
diff --git a/lib/842/842_compress.c b/lib/842/842_compress.c
index 7ce68948e68c..4051339bdfbd 100644
--- a/lib/842/842_compress.c
+++ b/lib/842/842_compress.c
@@ -490,6 +490,7 @@ int sw842_compress(const u8 *in, unsigned int ilen,
int ret;
u64 last, next, pad, total;
u8 repeat_count = 0;
+ u32 crc;
BUILD_BUG_ON(sizeof(*p) > SW842_MEM_COMPRESS);
@@ -580,6 +581,18 @@ skip_comp:
if (ret)
return ret;
+ /*
+ * crc(0:31) is appended to target data starting with the next
+ * bit after End of stream template.
+ * nx842 calculates CRC for data in big-endian format. So doing
+ * same here so that sw842 decompression can be used for both
+ * compressed data.
+ */
+ crc = crc32_be(0, in, ilen);
+ ret = add_bits(p, crc, CRC_BITS);
+ if (ret)
+ return ret;
+
if (p->bit) {
p->out++;
p->olen--;
diff --git a/lib/842/842_decompress.c b/lib/842/842_decompress.c
index 5446ff0c9ba0..8881dad2a6a0 100644
--- a/lib/842/842_decompress.c
+++ b/lib/842/842_decompress.c
@@ -285,6 +285,7 @@ int sw842_decompress(const u8 *in, unsigned int ilen,
struct sw842_param p;
int ret;
u64 op, rep, tmp, bytes, total;
+ u64 crc;
p.in = (u8 *)in;
p.bit = 0;
@@ -375,6 +376,22 @@ int sw842_decompress(const u8 *in, unsigned int ilen,
}
} while (op != OP_END);
+ /*
+ * crc(0:31) is saved in compressed data starting with the
+ * next bit after End of stream template.
+ */
+ ret = next_bits(&p, &crc, CRC_BITS);
+ if (ret)
+ return ret;
+
+ /*
+ * Validate CRC saved in compressed data.
+ */
+ if (crc != (u64)crc32_be(0, out, total - p.olen)) {
+ pr_debug("CRC mismatch for decompression\n");
+ return -EINVAL;
+ }
+
if (unlikely((total - p.olen) > UINT_MAX))
return -ENOSPC;
diff --git a/lib/Kconfig b/lib/Kconfig
index 2e491ac15622..f0df318104e7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -220,6 +220,7 @@ config ZLIB_INFLATE
config ZLIB_DEFLATE
tristate
+ select BITREVERSE
config LZO_COMPRESS
tristate
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index ab76b99adc85..1d1521c26302 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -197,6 +197,7 @@ config ENABLE_MUST_CHECK
config FRAME_WARN
int "Warn for stack frames larger than (needs gcc 4.4)"
range 0 8192
+ default 0 if KASAN
default 1024 if !64BIT
default 2048 if 64BIT
help
diff --git a/lib/Makefile b/lib/Makefile
index 13a7c6ae3fec..8de3b012eac7 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -26,7 +26,8 @@ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
bust_spinlocks.o kasprintf.o bitmap.o scatterlist.o \
gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \
bsearch.o find_bit.o llist.o memweight.o kfifo.o \
- percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o
+ percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o \
+ once.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
obj-y += hexdump.o
diff --git a/lib/devres.c b/lib/devres.c
index f13a2468ff39..8c85672639d3 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -418,7 +418,7 @@ void pcim_iounmap_regions(struct pci_dev *pdev, int mask)
if (!iomap)
return;
- for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+ for (i = 0; i < PCIM_IOMAP_MAX; i++) {
if (!(mask & (1 << i)))
continue;
diff --git a/lib/digsig.c b/lib/digsig.c
index ae05ea393fc8..07be6c1ef4e2 100644
--- a/lib/digsig.c
+++ b/lib/digsig.c
@@ -79,12 +79,13 @@ static int digsig_verify_rsa(struct key *key,
unsigned char *out1 = NULL;
const char *m;
MPI in = NULL, res = NULL, pkey[2];
- uint8_t *p, *datap, *endp;
- struct user_key_payload *ukp;
+ uint8_t *p, *datap;
+ const uint8_t *endp;
+ const struct user_key_payload *ukp;
struct pubkey_hdr *pkh;
down_read(&key->sem);
- ukp = key->payload.data;
+ ukp = user_key_payload(key);
if (ukp->datalen < sizeof(*pkh))
goto err1;
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index dace71fe41f7..fcb65d2a0b94 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -100,7 +100,7 @@ static LIST_HEAD(free_entries);
static DEFINE_SPINLOCK(free_entries_lock);
/* Global disable flag - will be set in case of an error */
-static u32 global_disable __read_mostly;
+static bool global_disable __read_mostly;
/* Early initialization disable flag, set at the end of dma_debug_init */
static bool dma_debug_initialized __read_mostly;
diff --git a/lib/fault-inject.c b/lib/fault-inject.c
index f1cdeb024d17..6a823a53e357 100644
--- a/lib/fault-inject.c
+++ b/lib/fault-inject.c
@@ -44,7 +44,7 @@ static void fail_dump(struct fault_attr *attr)
printk(KERN_NOTICE "FAULT_INJECTION: forcing a failure.\n"
"name %pd, interval %lu, probability %lu, "
"space %d, times %d\n", attr->dname,
- attr->probability, attr->interval,
+ attr->interval, attr->probability,
atomic_read(&attr->space),
atomic_read(&attr->times));
if (attr->verbose > 1)
diff --git a/lib/kobject.c b/lib/kobject.c
index 3e3a5c3cb330..055407746266 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -568,6 +568,7 @@ void kobject_del(struct kobject *kobj)
kobject_put(kobj->parent);
kobj->parent = NULL;
}
+EXPORT_SYMBOL(kobject_del);
/**
* kobject_get - increment refcount for object.
@@ -584,6 +585,7 @@ struct kobject *kobject_get(struct kobject *kobj)
}
return kobj;
}
+EXPORT_SYMBOL(kobject_get);
static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
{
@@ -675,6 +677,7 @@ void kobject_put(struct kobject *kobj)
kref_put(&kobj->kref, kobject_release);
}
}
+EXPORT_SYMBOL(kobject_put);
static void dynamic_kobj_release(struct kobject *kobj)
{
@@ -803,6 +806,7 @@ int kset_register(struct kset *k)
kobject_uevent(&k->kobj, KOBJ_ADD);
return 0;
}
+EXPORT_SYMBOL(kset_register);
/**
* kset_unregister - remove a kset.
@@ -815,6 +819,7 @@ void kset_unregister(struct kset *k)
kobject_del(&k->kobj);
kobject_put(&k->kobj);
}
+EXPORT_SYMBOL(kset_unregister);
/**
* kset_find_obj - search for object in kset.
@@ -1051,10 +1056,3 @@ void kobj_ns_drop(enum kobj_ns_type type, void *ns)
kobj_ns_ops_tbl[type]->drop_ns(ns);
spin_unlock(&kobj_ns_type_lock);
}
-
-EXPORT_SYMBOL(kobject_get);
-EXPORT_SYMBOL(kobject_put);
-EXPORT_SYMBOL(kobject_del);
-
-EXPORT_SYMBOL(kset_register);
-EXPORT_SYMBOL(kset_unregister);
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 95c52a95259e..c7e0a705eecf 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -319,3 +319,202 @@ int mpi_set_buffer(MPI a, const void *xbuffer, unsigned nbytes, int sign)
return 0;
}
EXPORT_SYMBOL_GPL(mpi_set_buffer);
+
+/**
+ * mpi_write_to_sgl() - Funnction exports MPI to an sgl (msb first)
+ *
+ * This function works in the same way as the mpi_read_buffer, but it
+ * takes an sgl instead of u8 * buf.
+ *
+ * @a: a multi precision integer
+ * @sgl: scatterlist to write to. Needs to be at least
+ * mpi_get_size(a) long.
+ * @nbytes: in/out param - it has the be set to the maximum number of
+ * bytes that can be written to sgl. This has to be at least
+ * the size of the integer a. On return it receives the actual
+ * length of the data written.
+ * @sign: if not NULL, it will be set to the sign of a.
+ *
+ * Return: 0 on success or error code in case of error
+ */
+int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
+ int *sign)
+{
+ u8 *p, *p2;
+ mpi_limb_t alimb, alimb2;
+ unsigned int n = mpi_get_size(a);
+ int i, x, y = 0, lzeros = 0, buf_len;
+
+ if (!nbytes || *nbytes < n)
+ return -EINVAL;
+
+ 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;
+ }
+
+ *nbytes = n - lzeros;
+ buf_len = sgl->length;
+ p2 = sg_virt(sgl);
+
+ for (i = a->nlimbs - 1; i >= 0; i--) {
+ alimb = a->d[i];
+ p = (u8 *)&alimb2;
+#if BYTES_PER_MPI_LIMB == 4
+ *p++ = alimb >> 24;
+ *p++ = alimb >> 16;
+ *p++ = alimb >> 8;
+ *p++ = alimb;
+#elif BYTES_PER_MPI_LIMB == 8
+ *p++ = alimb >> 56;
+ *p++ = alimb >> 48;
+ *p++ = alimb >> 40;
+ *p++ = alimb >> 32;
+ *p++ = alimb >> 24;
+ *p++ = alimb >> 16;
+ *p++ = alimb >> 8;
+ *p++ = alimb;
+#else
+#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;
+ }
+ lzeros -= sizeof(alimb);
+ }
+
+ p = p - (sizeof(alimb) - y);
+
+ for (x = 0; x < sizeof(alimb) - y; x++) {
+ if (!buf_len) {
+ sgl = sg_next(sgl);
+ if (!sgl)
+ return -EINVAL;
+ buf_len = sgl->length;
+ p2 = sg_virt(sgl);
+ }
+ *p2++ = *p++;
+ buf_len--;
+ }
+ y = 0;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_write_to_sgl);
+
+/*
+ * mpi_read_raw_from_sgl() - Function allocates an MPI and populates it with
+ * data from the sgl
+ *
+ * This function works in the same way as the mpi_read_raw_data, but it
+ * takes an sgl instead of void * buffer. i.e. it allocates
+ * a new MPI and reads the content of the sgl to the MPI.
+ *
+ * @sgl: scatterlist to read from
+ * @len: number of bytes to read
+ *
+ * Return: Pointer to a new MPI or NULL on error
+ */
+MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int len)
+{
+ struct scatterlist *sg;
+ int x, i, j, z, lzeros, ents;
+ unsigned int nbits, nlimbs, nbytes;
+ mpi_limb_t a;
+ MPI val = NULL;
+
+ lzeros = 0;
+ ents = sg_nents(sgl);
+
+ for_each_sg(sgl, sg, ents, i) {
+ const u8 *buff = sg_virt(sg);
+ int len = sg->length;
+
+ while (len && !*buff) {
+ lzeros++;
+ len--;
+ buff++;
+ }
+
+ if (len && *buff)
+ break;
+
+ ents--;
+ lzeros = 0;
+ }
+
+ sgl = sg;
+
+ if (!ents)
+ nbytes = 0;
+ else
+ nbytes = len - lzeros;
+
+ nbits = nbytes * 8;
+ if (nbits > MAX_EXTERN_MPI_BITS) {
+ pr_info("MPI: mpi too large (%u bits)\n", nbits);
+ return NULL;
+ }
+
+ if (nbytes > 0)
+ nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros));
+ else
+ nbits = 0;
+
+ nlimbs = DIV_ROUND_UP(nbytes, BYTES_PER_MPI_LIMB);
+ val = mpi_alloc(nlimbs);
+ if (!val)
+ return NULL;
+
+ val->nbits = nbits;
+ val->sign = 0;
+ val->nlimbs = nlimbs;
+
+ if (nbytes == 0)
+ return val;
+
+ j = nlimbs - 1;
+ a = 0;
+ z = 0;
+ x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
+ x %= BYTES_PER_MPI_LIMB;
+
+ for_each_sg(sgl, sg, ents, i) {
+ const u8 *buffer = sg_virt(sg) + lzeros;
+ int len = sg->length - lzeros;
+ int buf_shift = x;
+
+ if (sg_is_last(sg) && (len % BYTES_PER_MPI_LIMB))
+ len += BYTES_PER_MPI_LIMB - (len % BYTES_PER_MPI_LIMB);
+
+ for (; x < len + buf_shift; x++) {
+ a <<= 8;
+ a |= *buffer++;
+ if (((z + x + 1) % BYTES_PER_MPI_LIMB) == 0) {
+ val->d[j--] = a;
+ a = 0;
+ }
+ }
+ z += x;
+ x = 0;
+ lzeros = 0;
+ }
+ return val;
+}
+EXPORT_SYMBOL_GPL(mpi_read_raw_from_sgl);
diff --git a/lib/nmi_backtrace.c b/lib/nmi_backtrace.c
index 88d3d32e5923..6019c53c669e 100644
--- a/lib/nmi_backtrace.c
+++ b/lib/nmi_backtrace.c
@@ -43,6 +43,12 @@ static void print_seq_line(struct nmi_seq_buf *s, int start, int end)
printk("%.*s", (end - start) + 1, buf);
}
+/*
+ * When raise() is called it will be is passed a pointer to the
+ * backtrace_mask. Architectures that call nmi_cpu_backtrace()
+ * directly from their raise() functions may rely on the mask
+ * they are passed being updated as a side effect of this call.
+ */
void nmi_trigger_all_cpu_backtrace(bool include_self,
void (*raise)(cpumask_t *mask))
{
@@ -149,7 +155,10 @@ bool nmi_cpu_backtrace(struct pt_regs *regs)
/* Replace printk to write into the NMI seq */
this_cpu_write(printk_func, nmi_vprintk);
pr_warn("NMI backtrace for cpu %d\n", cpu);
- show_regs(regs);
+ if (regs)
+ show_regs(regs);
+ else
+ dump_stack();
this_cpu_write(printk_func, printk_func_save);
cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask));
diff --git a/lib/once.c b/lib/once.c
new file mode 100644
index 000000000000..05c8604627eb
--- /dev/null
+++ b/lib/once.c
@@ -0,0 +1,62 @@
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/once.h>
+#include <linux/random.h>
+
+struct once_work {
+ struct work_struct work;
+ struct static_key *key;
+};
+
+static void once_deferred(struct work_struct *w)
+{
+ struct once_work *work;
+
+ work = container_of(w, struct once_work, work);
+ BUG_ON(!static_key_enabled(work->key));
+ static_key_slow_dec(work->key);
+ kfree(work);
+}
+
+static void once_disable_jump(struct static_key *key)
+{
+ struct once_work *w;
+
+ w = kmalloc(sizeof(*w), GFP_ATOMIC);
+ if (!w)
+ return;
+
+ INIT_WORK(&w->work, once_deferred);
+ w->key = key;
+ schedule_work(&w->work);
+}
+
+static DEFINE_SPINLOCK(once_lock);
+
+bool __do_once_start(bool *done, unsigned long *flags)
+ __acquires(once_lock)
+{
+ spin_lock_irqsave(&once_lock, *flags);
+ if (*done) {
+ spin_unlock_irqrestore(&once_lock, *flags);
+ /* Keep sparse happy by restoring an even lock count on
+ * this lock. In case we return here, we don't call into
+ * __do_once_done but return early in the DO_ONCE() macro.
+ */
+ __acquire(once_lock);
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(__do_once_start);
+
+void __do_once_done(bool *done, struct static_key *once_key,
+ unsigned long *flags)
+ __releases(once_lock)
+{
+ *done = true;
+ spin_unlock_irqrestore(&once_lock, *flags);
+ once_disable_jump(once_key);
+}
+EXPORT_SYMBOL(__do_once_done);
diff --git a/lib/random32.c b/lib/random32.c
index 0bee183fa18f..12111910ccd0 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -181,7 +181,7 @@ void prandom_seed(u32 entropy)
* No locking on the CPUs, but then somewhat random results are, well,
* expected.
*/
- for_each_possible_cpu (i) {
+ for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state, i);
state->s1 = __seed(state->s1 ^ entropy, 2U);
@@ -201,7 +201,7 @@ static int __init prandom_init(void)
prandom_state_selftest();
for_each_possible_cpu(i) {
- struct rnd_state *state = &per_cpu(net_rand_state,i);
+ struct rnd_state *state = &per_cpu(net_rand_state, i);
u32 weak_seed = (i + jiffies) ^ random_get_entropy();
prandom_seed_early(state, weak_seed, true);
@@ -238,13 +238,30 @@ static void __init __prandom_start_seed_timer(void)
add_timer(&seed_timer);
}
+void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ struct rnd_state *state = per_cpu_ptr(pcpu_state, i);
+ u32 seeds[4];
+
+ get_random_bytes(&seeds, sizeof(seeds));
+ state->s1 = __seed(seeds[0], 2U);
+ state->s2 = __seed(seeds[1], 8U);
+ state->s3 = __seed(seeds[2], 16U);
+ state->s4 = __seed(seeds[3], 128U);
+
+ prandom_warmup(state);
+ }
+}
+
/*
* Generate better values after random number generator
* is fully initialized.
*/
static void __prandom_reseed(bool late)
{
- int i;
unsigned long flags;
static bool latch = false;
static DEFINE_SPINLOCK(lock);
@@ -266,19 +283,7 @@ static void __prandom_reseed(bool late)
goto out;
latch = true;
-
- for_each_possible_cpu(i) {
- struct rnd_state *state = &per_cpu(net_rand_state,i);
- u32 seeds[4];
-
- get_random_bytes(&seeds, sizeof(seeds));
- state->s1 = __seed(seeds[0], 2U);
- state->s2 = __seed(seeds[1], 8U);
- state->s3 = __seed(seeds[2], 16U);
- state->s4 = __seed(seeds[3], 128U);
-
- prandom_warmup(state);
- }
+ prandom_seed_full_state(&net_rand_state);
out:
spin_unlock_irqrestore(&lock, flags);
}
diff --git a/lib/string.c b/lib/string.c
index 13d1e84ddb80..84775ba873b9 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -27,6 +27,10 @@
#include <linux/bug.h>
#include <linux/errno.h>
+#include <asm/byteorder.h>
+#include <asm/word-at-a-time.h>
+#include <asm/page.h>
+
#ifndef __HAVE_ARCH_STRNCASECMP
/**
* strncasecmp - Case insensitive, length-limited string comparison
@@ -146,6 +150,91 @@ size_t strlcpy(char *dest, const char *src, size_t size)
EXPORT_SYMBOL(strlcpy);
#endif
+#ifndef __HAVE_ARCH_STRSCPY
+/**
+ * strscpy - Copy a C-string into a sized buffer
+ * @dest: Where to copy the string to
+ * @src: Where to copy the string from
+ * @count: Size of destination buffer
+ *
+ * Copy the string, or as much of it as fits, into the dest buffer.
+ * The routine returns the number of characters copied (not including
+ * the trailing NUL) or -E2BIG if the destination buffer wasn't big enough.
+ * The behavior is undefined if the string buffers overlap.
+ * The destination buffer is always NUL terminated, unless it's zero-sized.
+ *
+ * Preferred to strlcpy() since the API doesn't require reading memory
+ * from the src string beyond the specified "count" bytes, and since
+ * the return value is easier to error-check than strlcpy()'s.
+ * In addition, the implementation is robust to the string changing out
+ * from underneath it, unlike the current strlcpy() implementation.
+ *
+ * Preferred to strncpy() since it always returns a valid string, and
+ * doesn't unnecessarily force the tail of the destination buffer to be
+ * zeroed. If the zeroing is desired, it's likely cleaner to use strscpy()
+ * with an overflow test, then just memset() the tail of the dest buffer.
+ */
+ssize_t strscpy(char *dest, const char *src, size_t count)
+{
+ const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS;
+ size_t max = count;
+ long res = 0;
+
+ if (count == 0)
+ return -E2BIG;
+
+#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+ /*
+ * If src is unaligned, don't cross a page boundary,
+ * since we don't know if the next page is mapped.
+ */
+ if ((long)src & (sizeof(long) - 1)) {
+ size_t limit = PAGE_SIZE - ((long)src & (PAGE_SIZE - 1));
+ if (limit < max)
+ max = limit;
+ }
+#else
+ /* If src or dest is unaligned, don't do word-at-a-time. */
+ if (((long) dest | (long) src) & (sizeof(long) - 1))
+ max = 0;
+#endif
+
+ while (max >= sizeof(unsigned long)) {
+ unsigned long c, data;
+
+ c = *(unsigned long *)(src+res);
+ if (has_zero(c, &data, &constants)) {
+ data = prep_zero_mask(c, data, &constants);
+ data = create_zero_mask(data);
+ *(unsigned long *)(dest+res) = c & zero_bytemask(data);
+ return res + find_zero(data);
+ }
+ *(unsigned long *)(dest+res) = c;
+ res += sizeof(unsigned long);
+ count -= sizeof(unsigned long);
+ max -= sizeof(unsigned long);
+ }
+
+ while (count) {
+ char c;
+
+ c = src[res];
+ dest[res] = c;
+ if (!c)
+ return res;
+ res++;
+ count--;
+ }
+
+ /* Hit buffer length without finding a NUL; force NUL-termination. */
+ if (res)
+ dest[res-1] = '\0';
+
+ return -E2BIG;
+}
+EXPORT_SYMBOL(strscpy);
+#endif
+
#ifndef __HAVE_ARCH_STRCAT
/**
* strcat - Append one %NUL-terminated string to another