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authorHendrik Brueckner <brueckner@linux.vnet.ibm.com>2010-03-08 06:25:15 -0500
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2010-03-08 06:25:29 -0500
commit91a970d9889c7d6f451ee91ed361d0f0119d3778 (patch)
tree90cae28b66ac49543b3146194c88205c72f9f926 /drivers
parent596a95cdf0ba35ea353fb5b65750f596d712041e (diff)
[S390] hvc_iucv: allocate memory buffers for IUCV in zone DMA
The device driver must allocate memory for IUCV buffers with GFP_DMA, because IUCV cannot address memory above 2GB (31bit addresses only). Because the IUCV ignores the higher bits of the address, sending and receiving IUCV data with this driver might cause memory corruptions. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/char/hvc_iucv.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/char/hvc_iucv.c b/drivers/char/hvc_iucv.c
index 21681a81cc35..37b0542a4eeb 100644
--- a/drivers/char/hvc_iucv.c
+++ b/drivers/char/hvc_iucv.c
@@ -139,6 +139,8 @@ struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num)
139 * 139 *
140 * This function allocates a new struct iucv_tty_buffer element and, optionally, 140 * This function allocates a new struct iucv_tty_buffer element and, optionally,
141 * allocates an internal data buffer with the specified size @size. 141 * allocates an internal data buffer with the specified size @size.
142 * The internal data buffer is always allocated with GFP_DMA which is
143 * required for receiving and sending data with IUCV.
142 * Note: The total message size arises from the internal buffer size and the 144 * Note: The total message size arises from the internal buffer size and the
143 * members of the iucv_tty_msg structure. 145 * members of the iucv_tty_msg structure.
144 * The function returns NULL if memory allocation has failed. 146 * The function returns NULL if memory allocation has failed.
@@ -154,7 +156,7 @@ static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags)
154 156
155 if (size > 0) { 157 if (size > 0) {
156 bufp->msg.length = MSG_SIZE(size); 158 bufp->msg.length = MSG_SIZE(size);
157 bufp->mbuf = kmalloc(bufp->msg.length, flags); 159 bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA);
158 if (!bufp->mbuf) { 160 if (!bufp->mbuf) {
159 mempool_free(bufp, hvc_iucv_mempool); 161 mempool_free(bufp, hvc_iucv_mempool);
160 return NULL; 162 return NULL;
@@ -237,7 +239,7 @@ static int hvc_iucv_write(struct hvc_iucv_private *priv,
237 if (!rb->mbuf) { /* message not yet received ... */ 239 if (!rb->mbuf) { /* message not yet received ... */
238 /* allocate mem to store msg data; if no memory is available 240 /* allocate mem to store msg data; if no memory is available
239 * then leave the buffer on the list and re-try later */ 241 * then leave the buffer on the list and re-try later */
240 rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC); 242 rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA);
241 if (!rb->mbuf) 243 if (!rb->mbuf)
242 return -ENOMEM; 244 return -ENOMEM;
243 245