ide: dynamic allocation of device structures

Allocate device structures dynamically instead of having them embedded
in ide_hwif_t:

* Remove needless zeroing of port structure from ide_init_port_data().

* Add ide_hwif_t.devices[MAX_DRIVES] (table of pointers to the devices).

* Add ide_port_{alloc,free}_devices() helpers and use them respectively
  in ide_{host,free}_alloc().

* Convert all users of ->drives[] to use ->devices[] instead.

While at it:

* Use drive->dn for the slave device check in scc_pata.c.

As a nice side-effect this patch cuts ~1kB (x86-32) from the resulting
code size:

   text    data     bss     dec     hex filename
  53963    1244     237   55444    d894 drivers/ide/ide-core.o.before
  52981    1244     237   54462    d4be drivers/ide/ide-core.o.after

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 51 insertions, 20 deletions

diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
index 00c7e5a67bd1..006e601cafb8 100644
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -463,7 +463,7 @@ static int do_probe (ide_drive_t *drive, u8 cmd)
         if (ide_read_device(drive) != drive->select && present == 0) {
                 if (drive->dn & 1) {
                         /* exit with drive0 selected */
-                        SELECT_DRIVE(&hwif->drives[0]);
+                        SELECT_DRIVE(hwif->devices[0]);
                         /* allow ATA_BUSY to assert & clear */
                         msleep(50);
                 }
@@ -509,7 +509,7 @@ static int do_probe (ide_drive_t *drive, u8 cmd)
         }
         if (drive->dn & 1) {
                 /* exit with drive0 selected */
-                SELECT_DRIVE(&hwif->drives[0]);
+                SELECT_DRIVE(hwif->devices[0]);
                 msleep(50);
                 /* ensure drive irq is clear */
                 (void)tp_ops->read_status(hwif);
@@ -715,7 +715,7 @@ static int ide_port_wait_ready(ide_hwif_t *hwif)
 
         /* Now make sure both master & slave are ready */
         for (unit = 0; unit < MAX_DRIVES; unit++) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
 
                 /* Ignore disks that we will not probe for later. */
                 if ((drive->dev_flags & IDE_DFLAG_NOPROBE) == 0 ||
@@ -733,7 +733,7 @@ static int ide_port_wait_ready(ide_hwif_t *hwif)
 out:
         /* Exit function with master reselected (let's be sane) */
         if (unit)
-                SELECT_DRIVE(&hwif->drives[0]);
+                SELECT_DRIVE(hwif->devices[0]);
 
         return rc;
 }
@@ -749,7 +749,7 @@ out:
 
 void ide_undecoded_slave(ide_drive_t *dev1)
 {
-        ide_drive_t *dev0 = &dev1->hwif->drives[0];
+        ide_drive_t *dev0 = dev1->hwif->devices[0];
 
         if ((dev1->dn & 1) == 0 || (dev0->dev_flags & IDE_DFLAG_PRESENT) == 0)
                 return;
@@ -784,8 +784,8 @@ static int ide_probe_port(ide_hwif_t *hwif)
 
         BUG_ON(hwif->present);
 
-        if ((hwif->drives[0].dev_flags & IDE_DFLAG_NOPROBE) &&
-            (hwif->drives[1].dev_flags & IDE_DFLAG_NOPROBE))
+        if ((hwif->devices[0]->dev_flags & IDE_DFLAG_NOPROBE) &&
+            (hwif->devices[1]->dev_flags & IDE_DFLAG_NOPROBE))
                 return -EACCES;
 
         /*
@@ -807,7 +807,7 @@ static int ide_probe_port(ide_hwif_t *hwif)
          * but a lot of cdrom drives are configured as single slaves.
          */
         for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
 
                 (void) probe_for_drive(drive);
                 if (drive->dev_flags & IDE_DFLAG_PRESENT)
@@ -832,7 +832,7 @@ static void ide_port_tune_devices(ide_hwif_t *hwif)
         int unit;
 
         for (unit = 0; unit < MAX_DRIVES; unit++) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
 
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         if (port_ops && port_ops->quirkproc)
@@ -841,7 +841,7 @@ static void ide_port_tune_devices(ide_hwif_t *hwif)
         }
 
         for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
 
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         ide_set_max_pio(drive);
@@ -854,7 +854,7 @@ static void ide_port_tune_devices(ide_hwif_t *hwif)
         }
 
         for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
 
                 if ((hwif->host_flags & IDE_HFLAG_NO_IO_32BIT) ||
                     drive->id[ATA_ID_DWORD_IO])
@@ -931,7 +931,7 @@ static int ide_port_setup_devices(ide_hwif_t *hwif)
 
         mutex_lock(&ide_cfg_mtx);
         for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = &hwif->drives[i];
+                ide_drive_t *drive = hwif->devices[i];
 
                 if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
                         continue;
@@ -1017,7 +1017,7 @@ static struct kobject *ata_probe(dev_t dev, int *part, void *data)
 {
         ide_hwif_t *hwif = data;
         int unit = *part >> PARTN_BITS;
-        ide_drive_t *drive = &hwif->drives[unit];
+        ide_drive_t *drive = hwif->devices[unit];
 
         if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
                 return NULL;
@@ -1164,7 +1164,7 @@ static void hwif_register_devices(ide_hwif_t *hwif)
         unsigned int i;
 
         for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = &hwif->drives[i];
+                ide_drive_t *drive = hwif->devices[i];
                 struct device *dev = &drive->gendev;
                 int ret;
 
@@ -1190,7 +1190,7 @@ static void ide_port_init_devices(ide_hwif_t *hwif)
         int i;
 
         for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = &hwif->drives[i];
+                ide_drive_t *drive = hwif->devices[i];
 
                 drive->dn = i + hwif->channel * 2;
 
@@ -1285,7 +1285,7 @@ static void ide_port_init_devices_data(ide_hwif_t *hwif)
         int unit;
 
         for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = &hwif->drives[unit];
+                ide_drive_t *drive = hwif->devices[unit];
                 u8 j = (hwif->index * MAX_DRIVES) + unit;
 
                 memset(drive, 0, sizeof(*drive));
@@ -1309,9 +1309,6 @@ static void ide_port_init_devices_data(ide_hwif_t *hwif)
 
 static void ide_init_port_data(ide_hwif_t *hwif, unsigned int index)
 {
-        /* bulk initialize hwif & drive info with zeros */
-        memset(hwif, 0, sizeof(ide_hwif_t));
-
         /* fill in any non-zero initial values */
         hwif->index     = index;
         hwif->major     = ide_hwif_to_major[index];
@@ -1388,6 +1385,34 @@ static void ide_free_port_slot(int idx)
         mutex_unlock(&ide_cfg_mtx);
 }
 
+static void ide_port_free_devices(ide_hwif_t *hwif)
+{
+        int i;
+
+        for (i = 0; i < MAX_DRIVES; i++)
+                kfree(hwif->devices[i]);
+}
+
+static int ide_port_alloc_devices(ide_hwif_t *hwif, int node)
+{
+        int i;
+
+        for (i = 0; i < MAX_DRIVES; i++) {
+                ide_drive_t *drive;
+
+                drive = kzalloc_node(sizeof(*drive), GFP_KERNEL, node);
+                if (drive == NULL)
+                        goto out_nomem;
+
+                hwif->devices[i] = drive;
+        }
+        return 0;
+
+out_nomem:
+        ide_port_free_devices(hwif);
+        return -ENOMEM;
+}
+
 struct ide_host *ide_host_alloc(const struct ide_port_info *d, hw_regs_t **hws)
 {
         struct ide_host *host;
@@ -1410,6 +1435,11 @@ struct ide_host *ide_host_alloc(const struct ide_port_info *d, hw_regs_t **hws)
                 if (hwif == NULL)
                         continue;
 
+                if (ide_port_alloc_devices(hwif, node) < 0) {
+                        kfree(hwif);
+                        continue;
+                }
+
                 idx = ide_find_port_slot(d);
                 if (idx < 0) {
                         printk(KERN_ERR "%s: no free slot for interface\n",
@@ -1575,7 +1605,7 @@ static void __ide_port_unregister_devices(ide_hwif_t *hwif)
         int i;
 
         for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = &hwif->drives[i];
+                ide_drive_t *drive = hwif->devices[i];
 
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         device_unregister(&drive->gendev);
@@ -1651,6 +1681,7 @@ void ide_host_free(struct ide_host *host)
                 if (hwif == NULL)
                         continue;
 
+                ide_port_free_devices(hwif);
                 ide_free_port_slot(hwif->index);
                 kfree(hwif);
         }