GCC 8.1 warned:
In function 'rte_pktmbuf_prepend':
rte_mbuf.h:1908:17: warning: conversion from 'int' to 'uint16_t'
{aka 'short unsigned int'} may change value [-Wconversion]
m->data_off -= len;
^~~
m->data_off is a uint16_t
uint16_t data_off;
len (a uint16_t) is promoted to an int using -=. Do the
subtraction explicitly and cast the result to uint16_t.
The below += or -= changes are solving the same thing.
In function 'rte_pktmbuf_adj':
rte_mbuf.h:1969:17: warning: conversion from 'int' to 'uint16_t'
{aka 'short unsigned int'} may change value [-Wconversion]
m->data_off += len;
^~~
In function 'rte_pktmbuf_chain':
rte_mbuf.h:2082:19: warning: conversion from 'int' to 'uint16_t'
{aka 'short unsigned int'} may change value [-Wconversion]
head->nb_segs += tail->nb_segs;
^~~~
Also uint16_t
uint16_t nb_segs; /**< Number of segments. */
Fixes:
08b563ffb19d ("mbuf: replace data pointer by an offset")
Fixes:
1a60a0daa6e4 ("mbuf: fix segments number type increase")
Cc: stable@dpdk.org
Signed-off-by: Andy Green <andy@warmcat.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
if (unlikely(len > rte_pktmbuf_headroom(m)))
return NULL;
if (unlikely(len > rte_pktmbuf_headroom(m)))
return NULL;
+ /* NB: elaborating the subtraction like this instead of using
+ * -= allows us to ensure the result type is uint16_t
+ * avoiding compiler warnings on gcc 8.1 at least */
+ m->data_off = (uint16_t)(m->data_off - len);
m->data_len = (uint16_t)(m->data_len + len);
m->pkt_len = (m->pkt_len + len);
m->data_len = (uint16_t)(m->data_len + len);
m->pkt_len = (m->pkt_len + len);
if (unlikely(len > m->data_len))
return NULL;
if (unlikely(len > m->data_len))
return NULL;
+ /* NB: elaborating the addition like this instead of using
+ * += allows us to ensure the result type is uint16_t
+ * avoiding compiler warnings on gcc 8.1 at least */
m->data_len = (uint16_t)(m->data_len - len);
m->data_len = (uint16_t)(m->data_len - len);
+ m->data_off = (uint16_t)(m->data_off + len);
m->pkt_len = (m->pkt_len - len);
return (char *)m->buf_addr + m->data_off;
}
m->pkt_len = (m->pkt_len - len);
return (char *)m->buf_addr + m->data_off;
}
cur_tail = rte_pktmbuf_lastseg(head);
cur_tail->next = tail;
cur_tail = rte_pktmbuf_lastseg(head);
cur_tail->next = tail;
- /* accumulate number of segments and total length. */
- head->nb_segs += tail->nb_segs;
+ /* accumulate number of segments and total length.
+ * NB: elaborating the addition like this instead of using
+ * -= allows us to ensure the result type is uint16_t
+ * avoiding compiler warnings on gcc 8.1 at least */
+ head->nb_segs = (uint16_t)(head->nb_segs + tail->nb_segs);
head->pkt_len += tail->pkt_len;
/* pkt_len is only set in the head */
head->pkt_len += tail->pkt_len;
/* pkt_len is only set in the head */