[PATCH RFC PKS/PMEM 53/58] lib: Utilize new kmap_thread()

[ira.weiny@xxxxxxxxx]

From: Ira Weiny <ira.weiny@xxxxxxxxx>

These kmap() calls are localized to a single thread.  To avoid the over
head of global PKRS updates use the new kmap_thread() call.

Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx>
Cc: Martin KaFai Lau <kafai@xxxxxx>
Cc: Song Liu <songliubraving@xxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Cc: Andrii Nakryiko <andriin@xxxxxx>
Cc: John Fastabend <john.fastabend@xxxxxxxxx>
Cc: KP Singh <kpsingh@xxxxxxxxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
---
 lib/iov_iter.c | 12 ++++++------
 lib/test_bpf.c |  4 ++--
 lib/test_hmm.c |  8 ++++----
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 5e40786c8f12..1d47f957cf95 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -208,7 +208,7 @@ static size_t copy_page_to_iter_iovec(struct page *page, 
size_t offset, size_t b
        }
        /* Too bad - revert to non-atomic kmap */
 
-       kaddr = kmap(page);
+       kaddr = kmap_thread(page);
        from = kaddr + offset;
        left = copyout(buf, from, copy);
        copy -= left;
@@ -225,7 +225,7 @@ static size_t copy_page_to_iter_iovec(struct page *page, 
size_t offset, size_t b
                from += copy;
                bytes -= copy;
        }
-       kunmap(page);
+       kunmap_thread(page);
 
 done:
        if (skip == iov->iov_len) {
@@ -292,7 +292,7 @@ static size_t copy_page_from_iter_iovec(struct page *page, 
size_t offset, size_t
        }
        /* Too bad - revert to non-atomic kmap */
 
-       kaddr = kmap(page);
+       kaddr = kmap_thread(page);
        to = kaddr + offset;
        left = copyin(to, buf, copy);
        copy -= left;
@@ -309,7 +309,7 @@ static size_t copy_page_from_iter_iovec(struct page *page, 
size_t offset, size_t
                to += copy;
                bytes -= copy;
        }
-       kunmap(page);
+       kunmap_thread(page);
 
 done:
        if (skip == iov->iov_len) {
@@ -1742,10 +1742,10 @@ int iov_iter_for_each_range(struct iov_iter *i, size_t 
bytes,
                return 0;
 
        iterate_all_kinds(i, bytes, v, -EINVAL, ({
-               w.iov_base = kmap(v.bv_page) + v.bv_offset;
+               w.iov_base = kmap_thread(v.bv_page) + v.bv_offset;
                w.iov_len = v.bv_len;
                err = f(&w, context);
-               kunmap(v.bv_page);
+               kunmap_thread(v.bv_page);
                err;}), ({
                w = v;
                err = f(&w, context);})
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index ca7d635bccd9..441f822f56ba 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -6506,11 +6506,11 @@ static void *generate_test_data(struct bpf_test *test, 
int sub)
                if (!page)
                        goto err_kfree_skb;
 
-               ptr = kmap(page);
+               ptr = kmap_thread(page);
                if (!ptr)
                        goto err_free_page;
                memcpy(ptr, test->frag_data, MAX_DATA);
-               kunmap(page);
+               kunmap_thread(page);
                skb_add_rx_frag(skb, 0, page, 0, MAX_DATA, MAX_DATA);
        }
 
diff --git a/lib/test_hmm.c b/lib/test_hmm.c
index e7dc3de355b7..e40d26f97f45 100644
--- a/lib/test_hmm.c
+++ b/lib/test_hmm.c
@@ -329,9 +329,9 @@ static int dmirror_do_read(struct dmirror *dmirror, 
unsigned long start,
                if (!page)
                        return -ENOENT;
 
-               tmp = kmap(page);
+               tmp = kmap_thread(page);
                memcpy(ptr, tmp, PAGE_SIZE);
-               kunmap(page);
+               kunmap_thread(page);
 
                ptr += PAGE_SIZE;
                bounce->cpages++;
@@ -398,9 +398,9 @@ static int dmirror_do_write(struct dmirror *dmirror, 
unsigned long start,
                if (!page || xa_pointer_tag(entry) != DPT_XA_TAG_WRITE)
                        return -ENOENT;
 
-               tmp = kmap(page);
+               tmp = kmap_thread(page);
                memcpy(tmp, ptr, PAGE_SIZE);
-               kunmap(page);
+               kunmap_thread(page);
 
                ptr += PAGE_SIZE;
                bounce->cpages++;
-- 
2.28.0.rc0.12.gb6a658bd00c9