ide: fix PowerMac bootup oops

PowerMac bootup with CONFIG_IDE=y oopses in ide_pio_cycle_time():
because "ide: try to use PIO Mode 0 during probe if possible" causes
pmac_ide_set_pio_mode() to be called before drive->id has been set.

Bart points out other places which now need drive->id set earlier,
so follow his advice to allocate it in ide_port_alloc_devices()
(using kzalloc_node, without error message, as when allocating drive)
and memset it for reuse in ide_port_init_devices_data().

Fixed in passing: ide_host_alloc() was missing ide_port_free_devices()
from an error path.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Joao Ramos <joao.ramos@inov.pt>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 21 insertions, 26 deletions

diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
index f9c2fb7d0005..f371b0de314f 100644
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -465,23 +465,8 @@ static u8 probe_for_drive(ide_drive_t *drive)
         int rc;
         u8 cmd;
 
-        /*
-         *      In order to keep things simple we have an id
-         *      block for all drives at all times. If the device
-         *      is pre ATA or refuses ATA/ATAPI identify we
-         *      will add faked data to this.
-         *
-         *      Also note that 0 everywhere means "can't do X"
-         */
- 
         drive->dev_flags &= ~IDE_DFLAG_ID_READ;
 
-        drive->id = kzalloc(SECTOR_SIZE, GFP_KERNEL);
-        if (drive->id == NULL) {
-                printk(KERN_ERR "ide: out of memory for id data.\n");
-                return 0;
-        }
-
         m = (char *)&drive->id[ATA_ID_PROD];
         strcpy(m, "UNKNOWN");
 
@@ -497,7 +482,7 @@ static u8 probe_for_drive(ide_drive_t *drive)
                 }
 
                 if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
-                        goto out_free;
+                        return 0;
 
                 /* identification failed? */
                 if ((drive->dev_flags & IDE_DFLAG_ID_READ) == 0) {
@@ -521,7 +506,7 @@ static u8 probe_for_drive(ide_drive_t *drive)
         }
 
         if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
-                goto out_free;
+                return 0;
 
         /* The drive wasn't being helpful. Add generic info only */
         if ((drive->dev_flags & IDE_DFLAG_ID_READ) == 0) {
@@ -535,9 +520,6 @@ static u8 probe_for_drive(ide_drive_t *drive)
         }
 
         return 1;
-out_free:
-        kfree(drive->id);
-        return 0;
 }
 
 static void hwif_release_dev(struct device *dev)
@@ -825,8 +807,6 @@ static int ide_port_setup_devices(ide_hwif_t *hwif)
                 if (ide_init_queue(drive)) {
                         printk(KERN_ERR "ide: failed to init %s\n",
                                         drive->name);
-                        kfree(drive->id);
-                        drive->id = NULL;
                         drive->dev_flags &= ~IDE_DFLAG_PRESENT;
                         continue;
                 }
@@ -955,9 +935,6 @@ static void drive_release_dev (struct device *dev)
         blk_cleanup_queue(drive->queue);
         drive->queue = NULL;
 
-        kfree(drive->id);
-        drive->id = NULL;
-
         drive->dev_flags &= ~IDE_DFLAG_PRESENT;
 
         complete(&drive->gendev_rel_comp);
@@ -1140,8 +1117,11 @@ static void ide_port_init_devices_data(ide_hwif_t *hwif)
 
         ide_port_for_each_dev(i, drive, hwif) {
                 u8 j = (hwif->index * MAX_DRIVES) + i;
+                u16 *saved_id = drive->id;
 
                 memset(drive, 0, sizeof(*drive));
+                memset(saved_id, 0, SECTOR_SIZE);
+                drive->id = saved_id;
 
                 drive->media                    = ide_disk;
                 drive->select                   = (i << 4) | ATA_DEVICE_OBS;
@@ -1248,8 +1228,10 @@ static void ide_port_free_devices(ide_hwif_t *hwif)
         ide_drive_t *drive;
         int i;
 
-        ide_port_for_each_dev(i, drive, hwif)
+        ide_port_for_each_dev(i, drive, hwif) {
+                kfree(drive->id);
                 kfree(drive);
+        }
 }
 
 static int ide_port_alloc_devices(ide_hwif_t *hwif, int node)
@@ -1263,6 +1245,18 @@ static int ide_port_alloc_devices(ide_hwif_t *hwif, int node)
                 if (drive == NULL)
                         goto out_nomem;
 
+                /*
+                 * In order to keep things simple we have an id
+                 * block for all drives at all times. If the device
+                 * is pre ATA or refuses ATA/ATAPI identify we
+                 * will add faked data to this.
+                 *
+                 * Also note that 0 everywhere means "can't do X"
+                 */
+                drive->id = kzalloc_node(SECTOR_SIZE, GFP_KERNEL, node);
+                if (drive->id == NULL)
+                        goto out_nomem;
+
                 hwif->devices[i] = drive;
         }
         return 0;
@@ -1304,6 +1298,7 @@ struct ide_host *ide_host_alloc(const struct ide_port_info *d,
                 if (idx < 0) {
                         printk(KERN_ERR "%s: no free slot for interface\n",
                                         d ? d->name : "ide");
+                        ide_port_free_devices(hwif);
                         kfree(hwif);
                         continue;
                 }