ide: add port and host iterators

Add ide_port_for_each_dev() / ide_host_for_each_port() iterators
and update IDE code to use them.

While at it:
- s/unit/i/ variable in ide_port_wait_ready(), ide_probe_port(),
  ide_port_tune_devices(), ide_port_init_devices_data(), do_reset1(),
  ide_acpi_set_state() and scc_dma_end()
- s/d/i/ variable in ide_proc_port_register_devices()

There should be no functional changes caused by this patch.

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

7 files changed, 67 insertions, 85 deletions

diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
index fd155b8a256c..2f9e941968d6 100644
--- a/drivers/ide/ide-acpi.c
+++ b/drivers/ide/ide-acpi.c
@@ -641,7 +641,8 @@ void ide_acpi_push_timing(ide_hwif_t *hwif)
  */
 void ide_acpi_set_state(ide_hwif_t *hwif, int on)
 {
-        int unit;
+        ide_drive_t *drive;
+        int i;
 
         if (ide_noacpi || ide_noacpi_psx)
                 return;
@@ -655,9 +656,8 @@ void ide_acpi_set_state(ide_hwif_t *hwif, int on)
         /* channel first and then drives for power on and verse versa for power off */
         if (on)
                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
-        for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = hwif->devices[unit];
 
+        ide_port_for_each_dev(i, drive, hwif) {
                 if (!drive->acpidata->obj_handle)
                         drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
 
@@ -717,9 +717,7 @@ void ide_acpi_port_init_devices(ide_hwif_t *hwif)
         /*
          * Send IDENTIFY for each drive
          */
-        for (i = 0; i < MAX_DRIVES; i++) {
-                drive = hwif->devices[i];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 memset(drive->acpidata, 0, sizeof(*drive->acpidata));
 
                 if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
@@ -744,9 +742,7 @@ void ide_acpi_port_init_devices(ide_hwif_t *hwif)
         ide_acpi_get_timing(hwif);
         ide_acpi_push_timing(hwif);
 
-        for (i = 0; i < MAX_DRIVES; i++) {
-                drive = hwif->devices[i];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if (drive->dev_flags & IDE_DFLAG_PRESENT)
                         /* Execute ACPI startup code */
                         ide_acpi_exec_tfs(drive);
diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
index 26b58d15c4e6..1a22c31ce7ac 100644
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -1081,8 +1081,9 @@ static ide_startstop_t do_reset1 (ide_drive_t *drive, int do_not_try_atapi)
         struct ide_io_ports *io_ports = &hwif->io_ports;
         const struct ide_tp_ops *tp_ops = hwif->tp_ops;
         const struct ide_port_ops *port_ops;
+        ide_drive_t *tdrive;
         unsigned long flags, timeout;
-        unsigned int unit;
+        int i;
         DEFINE_WAIT(wait);
 
         spin_lock_irqsave(&hwif->lock, flags);
@@ -1110,9 +1111,7 @@ static ide_startstop_t do_reset1 (ide_drive_t *drive, int do_not_try_atapi)
 
                 prepare_to_wait(&ide_park_wq, &wait, TASK_UNINTERRUPTIBLE);
                 timeout = jiffies;
-                for (unit = 0; unit < MAX_DRIVES; unit++) {
-                        ide_drive_t *tdrive = hwif->devices[unit];
-
+                ide_port_for_each_dev(i, tdrive, hwif) {
                         if (tdrive->dev_flags & IDE_DFLAG_PRESENT &&
                             tdrive->dev_flags & IDE_DFLAG_PARKED &&
                             time_after(tdrive->sleep, timeout))
@@ -1133,8 +1132,8 @@ static ide_startstop_t do_reset1 (ide_drive_t *drive, int do_not_try_atapi)
          * First, reset any device state data we were maintaining
          * for any of the drives on this interface.
          */
-        for (unit = 0; unit < MAX_DRIVES; ++unit)
-                pre_reset(hwif->devices[unit]);
+        ide_port_for_each_dev(i, tdrive, hwif)
+                pre_reset(tdrive);
 
         if (io_ports->ctl_addr == 0) {
                 spin_unlock_irqrestore(&hwif->lock, flags);
diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c
index 006e601cafb8..e688ca1c967c 100644
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -697,7 +697,8 @@ out:
 
 static int ide_port_wait_ready(ide_hwif_t *hwif)
 {
-        int unit, rc;
+        ide_drive_t *drive;
+        int i, rc;
 
         printk(KERN_DEBUG "Probing IDE interface %s...\n", hwif->name);
 
@@ -714,9 +715,7 @@ static int ide_port_wait_ready(ide_hwif_t *hwif)
                 return rc;
 
         /* Now make sure both master & slave are ready */
-        for (unit = 0; unit < MAX_DRIVES; unit++) {
-                ide_drive_t *drive = hwif->devices[unit];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 /* Ignore disks that we will not probe for later. */
                 if ((drive->dev_flags & IDE_DFLAG_NOPROBE) == 0 ||
                     (drive->dev_flags & IDE_DFLAG_PRESENT)) {
@@ -732,7 +731,7 @@ static int ide_port_wait_ready(ide_hwif_t *hwif)
         }
 out:
         /* Exit function with master reselected (let's be sane) */
-        if (unit)
+        if (i)
                 SELECT_DRIVE(hwif->devices[0]);
 
         return rc;
@@ -778,9 +777,10 @@ EXPORT_SYMBOL_GPL(ide_undecoded_slave);
 
 static int ide_probe_port(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         unsigned long flags;
         unsigned int irqd;
-        int unit, rc = -ENODEV;
+        int i, rc = -ENODEV;
 
         BUG_ON(hwif->present);
 
@@ -806,9 +806,7 @@ static int ide_probe_port(ide_hwif_t *hwif)
          * Second drive should only exist if first drive was found,
          * but a lot of cdrom drives are configured as single slaves.
          */
-        for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = hwif->devices[unit];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 (void) probe_for_drive(drive);
                 if (drive->dev_flags & IDE_DFLAG_PRESENT)
                         rc = 0;
@@ -829,20 +827,17 @@ static int ide_probe_port(ide_hwif_t *hwif)
 static void ide_port_tune_devices(ide_hwif_t *hwif)
 {
         const struct ide_port_ops *port_ops = hwif->port_ops;
-        int unit;
-
-        for (unit = 0; unit < MAX_DRIVES; unit++) {
-                ide_drive_t *drive = hwif->devices[unit];
+        ide_drive_t *drive;
+        int i;
 
+        ide_port_for_each_dev(i, drive, hwif) {
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         if (port_ops && port_ops->quirkproc)
                                 port_ops->quirkproc(drive);
                 }
         }
 
-        for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = hwif->devices[unit];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         ide_set_max_pio(drive);
 
@@ -853,9 +848,7 @@ static void ide_port_tune_devices(ide_hwif_t *hwif)
                 }
         }
 
-        for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = hwif->devices[unit];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if ((hwif->host_flags & IDE_HFLAG_NO_IO_32BIT) ||
                     drive->id[ATA_ID_DWORD_IO])
                         drive->dev_flags |= IDE_DFLAG_NO_IO_32BIT;
@@ -927,12 +920,11 @@ static DEFINE_MUTEX(ide_cfg_mtx);
  */
 static int ide_port_setup_devices(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         int i, j = 0;
 
         mutex_lock(&ide_cfg_mtx);
-        for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = hwif->devices[i];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
                         continue;
 
@@ -1161,10 +1153,10 @@ out:
 
 static void hwif_register_devices(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         unsigned int i;
 
-        for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = hwif->devices[i];
+        ide_port_for_each_dev(i, drive, hwif) {
                 struct device *dev = &drive->gendev;
                 int ret;
 
@@ -1187,11 +1179,10 @@ static void hwif_register_devices(ide_hwif_t *hwif)
 static void ide_port_init_devices(ide_hwif_t *hwif)
 {
         const struct ide_port_ops *port_ops = hwif->port_ops;
+        ide_drive_t *drive;
         int i;
 
-        for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = hwif->devices[i];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 drive->dn = i + hwif->channel * 2;
 
                 if (hwif->host_flags & IDE_HFLAG_IO_32BIT)
@@ -1282,16 +1273,16 @@ static const u8 ide_hwif_to_major[] =
 
 static void ide_port_init_devices_data(ide_hwif_t *hwif)
 {
-        int unit;
+        ide_drive_t *drive;
+        int i;
 
-        for (unit = 0; unit < MAX_DRIVES; ++unit) {
-                ide_drive_t *drive = hwif->devices[unit];
-                u8 j = (hwif->index * MAX_DRIVES) + unit;
+        ide_port_for_each_dev(i, drive, hwif) {
+                u8 j = (hwif->index * MAX_DRIVES) + i;
 
                 memset(drive, 0, sizeof(*drive));
 
                 drive->media                    = ide_disk;
-                drive->select                   = (unit << 4) | ATA_DEVICE_OBS;
+                drive->select                   = (i << 4) | ATA_DEVICE_OBS;
                 drive->hwif                     = hwif;
                 drive->ready_stat               = ATA_DRDY;
                 drive->bad_wstat                = BAD_W_STAT;
@@ -1387,10 +1378,11 @@ static void ide_free_port_slot(int idx)
 
 static void ide_port_free_devices(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         int i;
 
-        for (i = 0; i < MAX_DRIVES; i++)
-                kfree(hwif->devices[i]);
+        ide_port_for_each_dev(i, drive, hwif)
+                kfree(drive);
 }
 
 static int ide_port_alloc_devices(ide_hwif_t *hwif, int node)
@@ -1478,9 +1470,7 @@ int ide_host_register(struct ide_host *host, const struct ide_port_info *d,
         ide_hwif_t *hwif, *mate = NULL;
         int i, j = 0;
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL) {
                         mate = NULL;
                         continue;
@@ -1506,9 +1496,7 @@ int ide_host_register(struct ide_host *host, const struct ide_port_info *d,
                 ide_port_init_devices(hwif);
         }
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL)
                         continue;
 
@@ -1523,9 +1511,7 @@ int ide_host_register(struct ide_host *host, const struct ide_port_info *d,
                         ide_port_tune_devices(hwif);
         }
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL)
                         continue;
 
@@ -1550,9 +1536,7 @@ int ide_host_register(struct ide_host *host, const struct ide_port_info *d,
                         ide_acpi_port_init_devices(hwif);
         }
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL)
                         continue;
 
@@ -1560,9 +1544,7 @@ int ide_host_register(struct ide_host *host, const struct ide_port_info *d,
                         hwif_register_devices(hwif);
         }
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL)
                         continue;
 
@@ -1602,11 +1584,10 @@ EXPORT_SYMBOL_GPL(ide_host_add);
 
 static void __ide_port_unregister_devices(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         int i;
 
-        for (i = 0; i < MAX_DRIVES; i++) {
-                ide_drive_t *drive = hwif->devices[i];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if (drive->dev_flags & IDE_DFLAG_PRESENT) {
                         device_unregister(&drive->gendev);
                         wait_for_completion(&drive->gendev_rel_comp);
@@ -1675,9 +1656,7 @@ void ide_host_free(struct ide_host *host)
         ide_hwif_t *hwif;
         int i;
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                hwif = host->ports[i];
-
+        ide_host_for_each_port(i, hwif, host) {
                 if (hwif == NULL)
                         continue;
 
@@ -1692,11 +1671,12 @@ EXPORT_SYMBOL_GPL(ide_host_free);
 
 void ide_host_remove(struct ide_host *host)
 {
+        ide_hwif_t *hwif;
         int i;
 
-        for (i = 0; i < MAX_HOST_PORTS; i++) {
-                if (host->ports[i])
-                        ide_unregister(host->ports[i]);
+        ide_host_for_each_port(i, hwif, host) {
+                if (hwif)
+                        ide_unregister(hwif);
         }
 
         ide_host_free(host);
diff --git a/drivers/ide/ide-proc.c b/drivers/ide/ide-proc.c
index 1dc827fa7061..1d8978b3314a 100644
--- a/drivers/ide/ide-proc.c
+++ b/drivers/ide/ide-proc.c
@@ -593,14 +593,13 @@ EXPORT_SYMBOL(ide_proc_unregister_driver);
 
 void ide_proc_port_register_devices(ide_hwif_t *hwif)
 {
-        int     d;
         struct proc_dir_entry *ent;
         struct proc_dir_entry *parent = hwif->proc;
+        ide_drive_t *drive;
         char name[64];
+        int i;
 
-        for (d = 0; d < MAX_DRIVES; d++) {
-                ide_drive_t *drive = hwif->devices[d];
-
+        ide_port_for_each_dev(i, drive, hwif) {
                 if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0 || drive->proc)
                         continue;
 
diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c
index 8a6f893d127e..258805da15c3 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -488,6 +488,7 @@ MODULE_PARM_DESC(ignore_cable, "ignore cable detection");
 
 void ide_port_apply_params(ide_hwif_t *hwif)
 {
+        ide_drive_t *drive;
         int i;
 
         if (ide_ignore_cable & (1 << hwif->index)) {
@@ -496,8 +497,8 @@ void ide_port_apply_params(ide_hwif_t *hwif)
                 hwif->cbl = ATA_CBL_PATA40_SHORT;
         }
 
-        for (i = 0; i < MAX_DRIVES; i++)
-                ide_dev_apply_params(hwif->devices[i], i);
+        ide_port_for_each_dev(i, drive, hwif)
+                ide_dev_apply_params(drive, i);
 }
 
 /*
diff --git a/drivers/ide/scc_pata.c b/drivers/ide/scc_pata.c
index 841164d7d3b9..5d53850c79d7 100644
--- a/drivers/ide/scc_pata.c
+++ b/drivers/ide/scc_pata.c
@@ -406,17 +406,17 @@ static int scc_dma_end(ide_drive_t *drive)
                         data_loss = 1;
                         if (retry++) {
                                 struct request *rq = hwif->rq;
-                                int unit;
+                                ide_drive_t *drive;
+                                int i;
+
                                 /* ERROR_RESET and drive->crc_count are needed
                                  * to reduce DMA transfer mode in retry process.
                                  */
                                 if (rq)
                                         rq->errors |= ERROR_RESET;
-                                for (unit = 0; unit < MAX_DRIVES; unit++) {
-                                        ide_drive_t *drive = hwif->devices[unit];
 
+                                ide_port_for_each_dev(i, drive, hwif)
                                         drive->crc_count++;
-                                }
                         }
                 }
         }
diff --git a/include/linux/ide.h b/include/linux/ide.h
index f00086b10be3..4cecd923fc79 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -753,7 +753,7 @@ typedef struct hwif_s {
 
         unsigned long   sata_scr[SATA_NR_PORTS];
 
-        ide_drive_t     *devices[MAX_DRIVES];
+        ide_drive_t     *devices[MAX_DRIVES + 1];
 
         u8 major;       /* our major number */
         u8 index;       /* 0 for ide0; 1 for ide1; ... */
@@ -861,7 +861,7 @@ typedef struct hwif_s {
 #define MAX_HOST_PORTS 4
 
 struct ide_host {
-        ide_hwif_t      *ports[MAX_HOST_PORTS];
+        ide_hwif_t      *ports[MAX_HOST_PORTS + 1];
         unsigned int    n_ports;
         struct device   *dev[2];
         unsigned int    (*init_chipset)(struct pci_dev *);
@@ -1604,4 +1604,11 @@ static inline ide_drive_t *ide_get_pair_dev(ide_drive_t *drive)
 
         return (peer->dev_flags & IDE_DFLAG_PRESENT) ? peer : NULL;
 }
+
+#define ide_port_for_each_dev(i, dev, port) \
+        for ((i) = 0; ((dev) = (port)->devices[i]) || (i) < MAX_DRIVES; (i)++)
+
+#define ide_host_for_each_port(i, port, host) \
+        for ((i) = 0; ((port) = (host)->ports[i]) || (i) < MAX_HOST_PORTS; (i)++)
+
 #endif /* _IDE_H */