libceph: make ceph_msg->bio_seg be unsigned

The bio_seg field is used by the ceph messenger in iterating through
a bio.  It should never have a negative value, so make it an
unsigned.  (I contemplated making it unsigned short to match the
struct bio definition, but it offered no benefit.)

Change variables used to hold bio_seg values to all be unsigned as
well.  Change two variable names in init_bio_iter() to match the
convention used everywhere else.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

2 files changed, 10 insertions, 8 deletions

diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
index 60903e0f665c..8297288a66e0 100644
--- a/include/linux/ceph/messenger.h
+++ b/include/linux/ceph/messenger.h
@@ -86,7 +86,7 @@ struct ceph_msg {
 #ifdef CONFIG_BLOCK
         struct bio  *bio;               /* instead of pages/pagelist */
         struct bio  *bio_iter;          /* bio iterator */
-        int bio_seg;                    /* current bio segment */
+        unsigned int bio_seg;           /* current bio segment */
 #endif /* CONFIG_BLOCK */
         struct ceph_pagelist *trail;    /* the trailing part of the data */
         bool front_is_vmalloc;
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 2c0669fb54e3..c06f94009d73 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -697,18 +697,19 @@ static void con_out_kvec_add(struct ceph_connection *con,
 }
 
 #ifdef CONFIG_BLOCK
-static void init_bio_iter(struct bio *bio, struct bio **iter, int *seg)
+static void init_bio_iter(struct bio *bio, struct bio **bio_iter,
+                        unsigned int *bio_seg)
 {
         if (!bio) {
-                *iter = NULL;
-                *seg = 0;
+                *bio_iter = NULL;
+                *bio_seg = 0;
                 return;
         }
-        *iter = bio;
-        *seg = bio->bi_idx;
+        *bio_iter = bio;
+        *bio_seg = (unsigned int) bio->bi_idx;
 }
 
-static void iter_bio_next(struct bio **bio_iter, int *seg)
+static void iter_bio_next(struct bio **bio_iter, unsigned int *seg)
 {
         if (*bio_iter == NULL)
                 return;
@@ -1818,7 +1819,8 @@ static int read_partial_message_pages(struct ceph_connection *con,
 
 #ifdef CONFIG_BLOCK
 static int read_partial_message_bio(struct ceph_connection *con,
-                                    struct bio **bio_iter, int *bio_seg,
+                                    struct bio **bio_iter,
+                                    unsigned int *bio_seg,
                                     unsigned int data_len, bool do_datacrc)
 {
         struct bio_vec *bv = bio_iovec_idx(*bio_iter, *bio_seg);