ide: switch to DMA-mapping API part #2

Follow-up to commit 5c05ff68b9a9b40a9be949497e0aa980185565cf
("ide: switch to DMA-mapping API"):

* pci_{alloc,free}_consistent() -> dma_{alloc,free}_coherent()
  in ide_{allocate,release}_dma_engine().

* Add ->prd_max_nents and ->prd_ent_size fields to ide_hwif_t
  (+ set default values in ide_allocate_dma_engine()).

* Make ide_{allocate,release}_dma_engine() available also
  for CONFIG_BLK_DEV_IDEDMA_SFF=n.  Then convert au1xxx-ide.c,
  scc_pata.c and sgiioc4.c to use them.

* Add missing ->init_dma method to scc_pata.

This patch also fixes:
- ->dmatable_cpu leak for au1xxx-ide
- too early realease of ->dmatable_cpu for scc_pata
- wrong amount of ->dmatable_cpu memory being freed for sgiioc4

While at it:
- remove superfluous ->dma_base check from ide_unregister()
- return -ENOMEM on error in ide_release_dma_engine()
- beautify error message in ide_release_dma_engine()

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

6 files changed, 47 insertions, 40 deletions

diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index 244b61b573ce..3f949b5db353 100644
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -844,36 +844,43 @@ void ide_dma_timeout(ide_drive_t *drive)
 }
 EXPORT_SYMBOL_GPL(ide_dma_timeout);
 
-#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
 void ide_release_dma_engine(ide_hwif_t *hwif)
 {
         if (hwif->dmatable_cpu) {
-                struct pci_dev *pdev = to_pci_dev(hwif->dev);
+                int prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 
-                pci_free_consistent(pdev, PRD_ENTRIES * PRD_BYTES,
-                                    hwif->dmatable_cpu, hwif->dmatable_dma);
+                dma_free_coherent(hwif->dev, prd_size,
+                                  hwif->dmatable_cpu, hwif->dmatable_dma);
                 hwif->dmatable_cpu = NULL;
         }
 }
+EXPORT_SYMBOL_GPL(ide_release_dma_engine);
 
 int ide_allocate_dma_engine(ide_hwif_t *hwif)
 {
-        struct pci_dev *pdev = to_pci_dev(hwif->dev);
+        int prd_size;
 
-        hwif->dmatable_cpu = pci_alloc_consistent(pdev,
-                                                  PRD_ENTRIES * PRD_BYTES,
-                                                  &hwif->dmatable_dma);
+        if (hwif->prd_max_nents == 0)
+                hwif->prd_max_nents = PRD_ENTRIES;
+        if (hwif->prd_ent_size == 0)
+                hwif->prd_ent_size = PRD_BYTES;
 
-        if (hwif->dmatable_cpu)
-                return 0;
+        prd_size = hwif->prd_max_nents * hwif->prd_ent_size;
 
-        printk(KERN_ERR "%s: -- Error, unable to allocate DMA table.\n",
+        hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev, prd_size,
+                                                &hwif->dmatable_dma,
+                                                GFP_ATOMIC);
+        if (hwif->dmatable_cpu == NULL) {
+                printk(KERN_ERR "%s: unable to allocate PRD table\n",
                         hwif->name);
+                return -ENOMEM;
+        }
 
-        return 1;
+        return 0;
 }
 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
 
+#ifdef CONFIG_BLK_DEV_IDEDMA_SFF
 const struct ide_dma_ops sff_dma_ops = {
         .dma_host_set           = ide_dma_host_set,
         .dma_setup              = ide_dma_setup,
diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c
index a498245dc213..083783e851d1 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -227,8 +227,7 @@ void ide_unregister(ide_hwif_t *hwif)
         kfree(hwif->sg_table);
         unregister_blkdev(hwif->major, hwif->name);
 
-        if (hwif->dma_base)
-                ide_release_dma_engine(hwif);
+        ide_release_dma_engine(hwif);
 
         mutex_unlock(&ide_cfg_mtx);
 }
diff --git a/drivers/ide/mips/au1xxx-ide.c b/drivers/ide/mips/au1xxx-ide.c
index f9e88cfec827..0ec8fd1e4dcb 100644
--- a/drivers/ide/mips/au1xxx-ide.c
+++ b/drivers/ide/mips/au1xxx-ide.c
@@ -427,10 +427,9 @@ static int auide_ddma_init(ide_hwif_t *hwif, const struct ide_port_info *d)
                                                              NUM_DESCRIPTORS);
         auide->rx_desc_head = (void*)au1xxx_dbdma_ring_alloc(auide->rx_chan,
                                                              NUM_DESCRIPTORS);
- 
-        hwif->dmatable_cpu = dma_alloc_coherent(hwif->dev,
-                                                PRD_ENTRIES * PRD_BYTES,        /* 1 Page */
-                                                &hwif->dmatable_dma, GFP_KERNEL);
+
+        /* FIXME: check return value */
+        (void)ide_allocate_dma_engine(hwif);
         
         au1xxx_dbdma_start( auide->tx_chan );
         au1xxx_dbdma_start( auide->rx_chan );
diff --git a/drivers/ide/pci/scc_pata.c b/drivers/ide/pci/scc_pata.c
index 3e75bf5f5e37..9ce1d8059921 100644
--- a/drivers/ide/pci/scc_pata.c
+++ b/drivers/ide/pci/scc_pata.c
@@ -821,6 +821,12 @@ static void __devinit init_iops_scc(ide_hwif_t *hwif)
         init_mmio_iops_scc(hwif);
 }
 
+static int __devinit scc_init_dma(ide_hwif_t *hwif,
+                                  const struct ide_port_info *d)
+{
+        return ide_allocate_dma_engine(hwif);
+}
+
 static u8 scc_cable_detect(ide_hwif_t *hwif)
 {
         return ATA_CBL_PATA80;
@@ -885,6 +891,7 @@ static const struct ide_dma_ops scc_dma_ops = {
   {                                                     \
       .name             = name_str,                     \
       .init_iops        = init_iops_scc,                \
+      .init_dma         = scc_init_dma,                 \
       .init_hwif        = init_hwif_scc,                \
       .tp_ops           = &scc_tp_ops,          \
       .port_ops         = &scc_port_ops,                \
@@ -922,13 +929,6 @@ static void __devexit scc_remove(struct pci_dev *dev)
 {
         struct scc_ports *ports = pci_get_drvdata(dev);
         struct ide_host *host = ports->host;
-        ide_hwif_t *hwif = host->ports[0];
-
-        if (hwif->dmatable_cpu) {
-                pci_free_consistent(dev, PRD_ENTRIES * PRD_BYTES,
-                                    hwif->dmatable_cpu, hwif->dmatable_dma);
-                hwif->dmatable_cpu = NULL;
-        }
 
         ide_host_remove(host);
 
diff --git a/drivers/ide/pci/sgiioc4.c b/drivers/ide/pci/sgiioc4.c
index 84cd986810cf..dd634541ce36 100644
--- a/drivers/ide/pci/sgiioc4.c
+++ b/drivers/ide/pci/sgiioc4.c
@@ -357,14 +357,13 @@ ide_dma_sgiioc4(ide_hwif_t *hwif, const struct ide_port_info *d)
         }
         hwif->dma_base = (unsigned long) virt_dma_base;
 
-        hwif->dmatable_cpu = pci_alloc_consistent(dev,
-                                          IOC4_PRD_ENTRIES * IOC4_PRD_BYTES,
-                                          &hwif->dmatable_dma);
+        hwif->sg_max_nents = IOC4_PRD_ENTRIES;
 
-        if (!hwif->dmatable_cpu)
-                goto dma_pci_alloc_failure;
+        hwif->prd_max_nents = IOC4_PRD_ENTRIES;
+        hwif->prd_ent_size = IOC4_PRD_BYTES;
 
-        hwif->sg_max_nents = IOC4_PRD_ENTRIES;
+        if (ide_allocate_dma_engine(hwif))
+                goto dma_pci_alloc_failure;
 
         pad = pci_alloc_consistent(dev, IOC4_IDE_CACHELINE_SIZE,
                                    (dma_addr_t *)&hwif->extra_base);
@@ -373,8 +372,8 @@ ide_dma_sgiioc4(ide_hwif_t *hwif, const struct ide_port_info *d)
                 return 0;
         }
 
-        pci_free_consistent(dev, IOC4_PRD_ENTRIES * IOC4_PRD_BYTES,
-                            hwif->dmatable_cpu, hwif->dmatable_dma);
+        ide_release_dma_engine(hwif);
+
         printk(KERN_ERR "%s(%s) -- ERROR: Unable to allocate DMA maps\n",
                __func__, hwif->name);
         printk(KERN_INFO "%s: changing from DMA to PIO mode", hwif->name);
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 39aaff8ff457..8121aa9240c4 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -788,6 +788,12 @@ typedef struct hwif_s {
         unsigned int    *dmatable_cpu;
         /* dma physical region descriptor table (dma view) */
         dma_addr_t      dmatable_dma;
+
+        /* maximum number of PRD table entries */
+        int prd_max_nents;
+        /* PRD entry size in bytes */
+        int prd_ent_size;
+
         /* Scatter-gather list used to build the above */
         struct scatterlist *sg_table;
         int sg_max_nents;               /* Maximum number of entries in it */
@@ -1423,14 +1429,14 @@ int ide_set_dma(ide_drive_t *);
 void ide_check_dma_crc(ide_drive_t *);
 ide_startstop_t ide_dma_intr(ide_drive_t *);
 
+int ide_allocate_dma_engine(ide_hwif_t *);
+void ide_release_dma_engine(ide_hwif_t *);
+
 int ide_build_sglist(ide_drive_t *, struct request *);
 void ide_destroy_dmatable(ide_drive_t *);
 
 #ifdef CONFIG_BLK_DEV_IDEDMA_SFF
 extern int ide_build_dmatable(ide_drive_t *, struct request *);
-int ide_allocate_dma_engine(ide_hwif_t *);
-void ide_release_dma_engine(ide_hwif_t *);
-
 void ide_dma_host_set(ide_drive_t *, int);
 extern int ide_dma_setup(ide_drive_t *);
 void ide_dma_exec_cmd(ide_drive_t *, u8);
@@ -1453,11 +1459,8 @@ static inline void ide_dma_on(ide_drive_t *drive) { ; }
 static inline void ide_dma_verbose(ide_drive_t *drive) { ; }
 static inline int ide_set_dma(ide_drive_t *drive) { return 1; }
 static inline void ide_check_dma_crc(ide_drive_t *drive) { ; }
-#endif /* CONFIG_BLK_DEV_IDEDMA */
-
-#ifndef CONFIG_BLK_DEV_IDEDMA_SFF
 static inline void ide_release_dma_engine(ide_hwif_t *hwif) { ; }
-#endif
+#endif /* CONFIG_BLK_DEV_IDEDMA */
 
 #ifdef CONFIG_BLK_DEV_IDEACPI
 extern int ide_acpi_exec_tfs(ide_drive_t *drive);