[PATCH] libata: use preallocated buffers
It's not a very good idea to allocate memory during EH. Use
statically allocated buffer for dev->id[] and add 512byte buffer
ap->sector_buf. This buffer is owned by EH (or probing) and to be
used as temporary buffer for various purposes (IDENTIFY, NCQ log page
10h, PM GSCR block).
Signed-off-by: Tejun Heo <htejun@gmail.com>
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 13bce43..af55861 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1099,7 +1099,7 @@
* @dev: target device
* @p_class: pointer to class of the target device (may be changed)
* @post_reset: is this read ID post-reset?
- * @p_id: read IDENTIFY page (newly allocated)
+ * @id: buffer to read IDENTIFY data into
*
* Read ID data from the specified device. ATA_CMD_ID_ATA is
* performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
@@ -1113,12 +1113,11 @@
* 0 on success, -errno otherwise.
*/
static int ata_dev_read_id(struct ata_port *ap, struct ata_device *dev,
- unsigned int *p_class, int post_reset, u16 **p_id)
+ unsigned int *p_class, int post_reset, u16 *id)
{
unsigned int class = *p_class;
struct ata_taskfile tf;
unsigned int err_mask = 0;
- u16 *id;
const char *reason;
int rc;
@@ -1126,13 +1125,6 @@
ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */
- id = kmalloc(sizeof(id[0]) * ATA_ID_WORDS, GFP_KERNEL);
- if (id == NULL) {
- rc = -ENOMEM;
- reason = "out of memory";
- goto err_out;
- }
-
retry:
ata_tf_init(ap, &tf, dev->devno);
@@ -1194,13 +1186,12 @@
}
*p_class = class;
- *p_id = id;
+
return 0;
err_out:
printk(KERN_WARNING "ata%u: dev %u failed to IDENTIFY (%s)\n",
ap->id, dev->devno, reason);
- kfree(id);
return rc;
}
@@ -1425,9 +1416,7 @@
if (!ata_dev_enabled(dev))
continue;
- kfree(dev->id);
- dev->id = NULL;
- rc = ata_dev_read_id(ap, dev, &dev->class, 1, &dev->id);
+ rc = ata_dev_read_id(ap, dev, &dev->class, 1, dev->id);
if (rc)
goto fail;
@@ -2788,7 +2777,7 @@
int post_reset)
{
unsigned int class = dev->class;
- u16 *id = NULL;
+ u16 *id = (void *)ap->sector_buf;
int rc;
if (!ata_dev_enabled(dev)) {
@@ -2796,8 +2785,8 @@
goto fail;
}
- /* allocate & read ID data */
- rc = ata_dev_read_id(ap, dev, &class, post_reset, &id);
+ /* read ID data */
+ rc = ata_dev_read_id(ap, dev, &class, post_reset, id);
if (rc)
goto fail;
@@ -2807,8 +2796,7 @@
goto fail;
}
- kfree(dev->id);
- dev->id = id;
+ memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
/* configure device according to the new ID */
rc = ata_dev_configure(ap, dev, 0);
@@ -2818,7 +2806,6 @@
fail:
printk(KERN_ERR "ata%u: dev %u revalidation failed (errno=%d)\n",
ap->id, dev->devno, rc);
- kfree(id);
return rc;
}
@@ -4873,14 +4860,11 @@
int ata_scsi_release(struct Scsi_Host *host)
{
struct ata_port *ap = ata_shost_to_port(host);
- int i;
DPRINTK("ENTER\n");
ap->ops->port_disable(ap);
ata_host_remove(ap, 0);
- for (i = 0; i < ATA_MAX_DEVICES; i++)
- kfree(ap->device[i].id);
DPRINTK("EXIT\n");
return 1;