[libata] ATAPI pad allocation fixes/cleanup

Use ata_pad_{alloc,free} in two drivers, to factor out common code.

Add ata_pad_{alloc,free} to two other drivers, which needed the padding
but had not been updated.

5 files changed, 71 insertions, 26 deletions

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index 8420204c2eaa..4612312c0c2d 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -307,21 +307,22 @@ static int ahci_port_start(struct ata_port *ap)
         void __iomem *port_mmio = ahci_port_base(mmio, ap->port_no);
         void *mem;
         dma_addr_t mem_dma;
+        int rc;
 
         pp = kmalloc(sizeof(*pp), GFP_KERNEL);
         if (!pp)
                 return -ENOMEM;
         memset(pp, 0, sizeof(*pp));
 
-        ap->pad = dma_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ, &ap->pad_dma, GFP_KERNEL);
-        if (!ap->pad) {
+        rc = ata_pad_alloc(ap, dev);
+        if (rc) {
                 kfree(pp);
-                return -ENOMEM;
+                return rc;
         }
 
         mem = dma_alloc_coherent(dev, AHCI_PORT_PRIV_DMA_SZ, &mem_dma, GFP_KERNEL);
         if (!mem) {
-                dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
+                ata_pad_free(ap, dev);
                 kfree(pp);
                 return -ENOMEM;
         }
@@ -397,7 +398,7 @@ static void ahci_port_stop(struct ata_port *ap)
         ap->private_data = NULL;
         dma_free_coherent(dev, AHCI_PORT_PRIV_DMA_SZ,
                           pp->cmd_slot, pp->cmd_slot_dma);
-        dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
+        ata_pad_free(ap, dev);
         kfree(pp);
 }
 
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index ae2475e4291c..e1346cddd37f 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4091,15 +4091,16 @@ err_out:
 int ata_port_start (struct ata_port *ap)
 {
         struct device *dev = ap->host_set->dev;
+        int rc;
 
         ap->prd = dma_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma, GFP_KERNEL);
         if (!ap->prd)
                 return -ENOMEM;
 
-        ap->pad = dma_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ, &ap->pad_dma, GFP_KERNEL);
-        if (!ap->pad) {
+        rc = ata_pad_alloc(ap, dev);
+        if (rc) {
                 dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
-                return -ENOMEM;
+                return rc;
         }
 
         DPRINTK("prd alloc, virt %p, dma %llx\n", ap->prd, (unsigned long long) ap->prd_dma);
@@ -4125,7 +4126,7 @@ void ata_port_stop (struct ata_port *ap)
         struct device *dev = ap->host_set->dev;
 
         dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
-        dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
+        ata_pad_free(ap, dev);
 }
 
 void ata_host_stop (struct ata_host_set *host_set)
diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c
index 64af334e71f4..0f469e3dabe2 100644
--- a/drivers/scsi/sata_mv.c
+++ b/drivers/scsi/sata_mv.c
@@ -670,6 +670,11 @@ static void mv_host_stop(struct ata_host_set *host_set)
         ata_host_stop(host_set);
 }
 
+static inline void mv_priv_free(struct mv_port_priv *pp, struct device *dev)
+{
+        dma_free_coherent(dev, MV_PORT_PRIV_DMA_SZ, pp->crpb, pp->crpb_dma);
+}
+
 /**
  *      mv_port_start - Port specific init/start routine.
  *      @ap: ATA channel to manipulate
@@ -687,21 +692,23 @@ static int mv_port_start(struct ata_port *ap)
         void __iomem *port_mmio = mv_ap_base(ap);
         void *mem;
         dma_addr_t mem_dma;
+        int rc = -ENOMEM;
 
         pp = kmalloc(sizeof(*pp), GFP_KERNEL);
-        if (!pp) {
-                return -ENOMEM;
-        }
+        if (!pp)
+                goto err_out;
         memset(pp, 0, sizeof(*pp));
 
         mem = dma_alloc_coherent(dev, MV_PORT_PRIV_DMA_SZ, &mem_dma, 
                                  GFP_KERNEL);
-        if (!mem) {
-                kfree(pp);
-                return -ENOMEM;
-        }
+        if (!mem)
+                goto err_out_pp;
         memset(mem, 0, MV_PORT_PRIV_DMA_SZ);
 
+        rc = ata_pad_alloc(ap, dev);
+        if (rc)
+                goto err_out_priv;
+
         /* First item in chunk of DMA memory: 
          * 32-slot command request table (CRQB), 32 bytes each in size
          */
@@ -746,6 +753,13 @@ static int mv_port_start(struct ata_port *ap)
          */
         ap->private_data = pp;
         return 0;
+
+err_out_priv:
+        mv_priv_free(pp, dev);
+err_out_pp:
+        kfree(pp);
+err_out:
+        return rc;
 }
 
 /**
@@ -768,7 +782,8 @@ static void mv_port_stop(struct ata_port *ap)
         spin_unlock_irqrestore(&ap->host_set->lock, flags);
 
         ap->private_data = NULL;
-        dma_free_coherent(dev, MV_PORT_PRIV_DMA_SZ, pp->crpb, pp->crpb_dma);
+        ata_pad_free(ap, dev);
+        mv_priv_free(pp, dev);
         kfree(pp);
 }
 
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index 211ec7eebc9c..e6c8e89c226f 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -635,6 +635,13 @@ static irqreturn_t sil24_interrupt(int irq, void *dev_instance, struct pt_regs *
         return IRQ_RETVAL(handled);
 }
 
+static inline void sil24_cblk_free(struct sil24_port_priv *pp, struct device *dev)
+{
+        const size_t cb_size = sizeof(*pp->cmd_block);
+
+        dma_free_coherent(dev, cb_size, pp->cmd_block, pp->cmd_block_dma);
+}
+
 static int sil24_port_start(struct ata_port *ap)
 {
         struct device *dev = ap->host_set->dev;
@@ -642,36 +649,44 @@ static int sil24_port_start(struct ata_port *ap)
         struct sil24_cmd_block *cb;
         size_t cb_size = sizeof(*cb);
         dma_addr_t cb_dma;
+        int rc = -ENOMEM;
 
-        pp = kmalloc(sizeof(*pp), GFP_KERNEL);
+        pp = kzalloc(sizeof(*pp), GFP_KERNEL);
         if (!pp)
-                return -ENOMEM;
-        memset(pp, 0, sizeof(*pp));
+                goto err_out;
 
         pp->tf.command = ATA_DRDY;
 
         cb = dma_alloc_coherent(dev, cb_size, &cb_dma, GFP_KERNEL);
-        if (!cb) {
-                kfree(pp);
-                return -ENOMEM;
-        }
+        if (!cb)
+                goto err_out_pp;
         memset(cb, 0, cb_size);
 
+        rc = ata_pad_alloc(ap, dev);
+        if (rc)
+                goto err_out_pad;
+
         pp->cmd_block = cb;
         pp->cmd_block_dma = cb_dma;
 
         ap->private_data = pp;
 
         return 0;
+
+err_out_pad:
+        sil24_cblk_free(pp, dev);
+err_out_pp:
+        kfree(pp);
+err_out:
+        return rc;
 }
 
 static void sil24_port_stop(struct ata_port *ap)
 {
         struct device *dev = ap->host_set->dev;
         struct sil24_port_priv *pp = ap->private_data;
-        size_t cb_size = sizeof(*pp->cmd_block);
 
-        dma_free_coherent(dev, cb_size, pp->cmd_block, pp->cmd_block_dma);
+        sil24_cblk_free(pp, dev);
         kfree(pp);
 }
 
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6225b78fa65b..dcd17e7458ab 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -777,4 +777,17 @@ static inline unsigned int __ac_err_mask(u8 status)
         return mask;
 }
 
+static inline int ata_pad_alloc(struct ata_port *ap, struct device *dev)
+{
+        ap->pad_dma = 0;
+        ap->pad = dma_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ,
+                                     &ap->pad_dma, GFP_KERNEL);
+        return (ap->pad == NULL) ? -ENOMEM : 0;
+}
+
+static inline void ata_pad_free(struct ata_port *ap, struct device *dev)
+{
+        dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
+}
+
 #endif /* __LINUX_LIBATA_H__ */