ARM64: dts: rockchip: add cpuinfo support for rk3328

[firefly-linux-kernel-4.4.55.git] / lib / iov_iter.c

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 9d96e283520cc7f3ec27714dfa4abfcb3800e319..daca582a8ed072f0b4eb8b6871134a608e3192b1 100644 (file)
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -298,20 +298,26 @@ 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).
+ * 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.
  *
- * 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).
+ * 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_readable(struct iov_iter *i, size_t bytes)
 {
+       size_t skip = i->iov_offset;
+       const struct iovec *iov;
+       int err;
+       struct iovec v;
+
        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);
+               iterate_iovec(i, bytes, v, iov, skip, ({
+                       err = fault_in_multipages_readable(v.iov_base,
+                                       v.iov_len);
+                       if (unlikely(err))
+                       return err;
+               0;}))
        }
        return 0;
 }
@@ -766,3 +772,60 @@ const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
                                   flags);
 }
 EXPORT_SYMBOL(dup_iter);
+
+int import_iovec(int type, const struct iovec __user * uvector,
+                unsigned nr_segs, unsigned fast_segs,
+                struct iovec **iov, struct iov_iter *i)
+{
+       ssize_t n;
+       struct iovec *p;
+       n = rw_copy_check_uvector(type, uvector, nr_segs, fast_segs,
+                                 *iov, &p);
+       if (n < 0) {
+               if (p != *iov)
+                       kfree(p);
+               *iov = NULL;
+               return n;
+       }
+       iov_iter_init(i, type, p, nr_segs, n);
+       *iov = p == *iov ? NULL : p;
+       return 0;
+}
+EXPORT_SYMBOL(import_iovec);
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+
+int compat_import_iovec(int type, const struct compat_iovec __user * uvector,
+                unsigned nr_segs, unsigned fast_segs,
+                struct iovec **iov, struct iov_iter *i)
+{
+       ssize_t n;
+       struct iovec *p;
+       n = compat_rw_copy_check_uvector(type, uvector, nr_segs, fast_segs,
+                                 *iov, &p);
+       if (n < 0) {
+               if (p != *iov)
+                       kfree(p);
+               *iov = NULL;
+               return n;
+       }
+       iov_iter_init(i, type, p, nr_segs, n);
+       *iov = p == *iov ? NULL : p;
+       return 0;
+}
+#endif
+
+int import_single_range(int rw, void __user *buf, size_t len,
+                struct iovec *iov, struct iov_iter *i)
+{
+       if (len > MAX_RW_COUNT)
+               len = MAX_RW_COUNT;
+       if (unlikely(!access_ok(!rw, buf, len)))
+               return -EFAULT;
+
+       iov->iov_base = buf;
+       iov->iov_len = len;
+       iov_iter_init(i, rw, iov, 1, len);
+       return 0;
+}