[PATCH] Char: stallion, implement fail paths

This driver expect everything to work.  Implement fail paths logic to release
regions, irq hangler, memory...  if something is in bad state.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 128 insertions, 71 deletions

diff --git a/drivers/char/stallion.c b/drivers/char/stallion.c
index bc2911396b7e..24bdb48310c2 100644
--- a/drivers/char/stallion.c
+++ b/drivers/char/stallion.c
@@ -779,7 +779,8 @@ static void __init stl_argbrds(void)
                 brdp->ioaddr2 = conf.ioaddr2;
                 brdp->irq = conf.irq;
                 brdp->irqtype = conf.irqtype;
-                stl_brdinit(brdp);
+                if (stl_brdinit(brdp))
+                        kfree(brdp);
         }
 }
 
@@ -1965,6 +1966,29 @@ static int __init stl_initports(struct stlbrd *brdp, struct stlpanel *panelp)
         return(0);
 }
 
+static void stl_cleanup_panels(struct stlbrd *brdp)
+{
+        struct stlpanel *panelp;
+        struct stlport *portp;
+        unsigned int j, k;
+
+        for (j = 0; j < STL_MAXPANELS; j++) {
+                panelp = brdp->panels[j];
+                if (panelp == NULL)
+                        continue;
+                for (k = 0; k < STL_PORTSPERPANEL; k++) {
+                        portp = panelp->ports[k];
+                        if (portp == NULL)
+                                continue;
+                        if (portp->tty != NULL)
+                                stl_hangup(portp->tty);
+                        kfree(portp->tx.buf);
+                        kfree(portp);
+                }
+                kfree(panelp);
+        }
+}
+
 /*****************************************************************************/
 
 /*
@@ -1976,7 +2000,7 @@ static int __init stl_initeio(struct stlbrd *brdp)
         struct stlpanel *panelp;
         unsigned int    status;
         char            *name;
-        int             rc;
+        int             retval;
 
         pr_debug("stl_initeio(brdp=%p)\n", brdp);
 
@@ -2003,18 +2027,20 @@ static int __init stl_initeio(struct stlbrd *brdp)
                     (stl_vecmap[brdp->irq] == (unsigned char) 0xff)) {
                         printk("STALLION: invalid irq=%d for brd=%d\n",
                                 brdp->irq, brdp->brdnr);
-                        return(-EINVAL);
+                        retval = -EINVAL;
+                        goto err;
                 }
                 outb((stl_vecmap[brdp->irq] | EIO_0WS |
                         ((brdp->irqtype) ? EIO_INTLEVEL : EIO_INTEDGE)),
                         brdp->ioctrl);
         }
 
+        retval = -EBUSY;
         if (!request_region(brdp->ioaddr1, brdp->iosize1, name)) {
                 printk(KERN_WARNING "STALLION: Warning, board %d I/O address "
                         "%x conflicts with another device\n", brdp->brdnr, 
                         brdp->ioaddr1);
-                return(-EBUSY);
+                goto err;
         }
         
         if (brdp->iosize2 > 0)
@@ -2025,8 +2051,7 @@ static int __init stl_initeio(struct stlbrd *brdp)
                         printk(KERN_WARNING "STALLION: Warning, also "
                                 "releasing board %d I/O address %x \n", 
                                 brdp->brdnr, brdp->ioaddr1);
-                        release_region(brdp->ioaddr1, brdp->iosize1);
-                        return(-EBUSY);
+                        goto err_rel1;
                 }
 
 /*
@@ -2035,6 +2060,7 @@ static int __init stl_initeio(struct stlbrd *brdp)
         brdp->clk = CD1400_CLK;
         brdp->isr = stl_eiointr;
 
+        retval = -ENODEV;
         switch (status & EIO_IDBITMASK) {
         case EIO_8PORTM:
                 brdp->clk = CD1400_CLK8M;
@@ -2058,11 +2084,11 @@ static int __init stl_initeio(struct stlbrd *brdp)
                         brdp->nrports = 16;
                         break;
                 default:
-                        return(-ENODEV);
+                        goto err_rel2;
                 }
                 break;
         default:
-                return(-ENODEV);
+                goto err_rel2;
         }
 
 /*
@@ -2074,7 +2100,8 @@ static int __init stl_initeio(struct stlbrd *brdp)
         if (!panelp) {
                 printk(KERN_WARNING "STALLION: failed to allocate memory "
                         "(size=%Zd)\n", sizeof(struct stlpanel));
-                return -ENOMEM;
+                retval = -ENOMEM;
+                goto err_rel2;
         }
 
         panelp->magic = STL_PANELMAGIC;
@@ -2098,11 +2125,20 @@ static int __init stl_initeio(struct stlbrd *brdp)
         if (request_irq(brdp->irq, stl_intr, IRQF_SHARED, name, brdp) != 0) {
                 printk("STALLION: failed to register interrupt "
                     "routine for %s irq=%d\n", name, brdp->irq);
-                rc = -ENODEV;
-        } else {
-                rc = 0;
+                retval = -ENODEV;
+                goto err_fr;
         }
-        return rc;
+
+        return 0;
+err_fr:
+        stl_cleanup_panels(brdp);
+err_rel2:
+        if (brdp->iosize2 > 0)
+                release_region(brdp->ioaddr2, brdp->iosize2);
+err_rel1:
+        release_region(brdp->ioaddr1, brdp->iosize1);
+err:
+        return retval;
 }
 
 /*****************************************************************************/
@@ -2116,7 +2152,7 @@ static int __init stl_initech(struct stlbrd *brdp)
 {
         struct stlpanel *panelp;
         unsigned int    status, nxtid, ioaddr, conflict;
-        int             panelnr, banknr, i;
+        int             panelnr, banknr, i, retval;
         char            *name;
 
         pr_debug("stl_initech(brdp=%p)\n", brdp);
@@ -2136,13 +2172,16 @@ static int __init stl_initech(struct stlbrd *brdp)
                 brdp->ioctrl = brdp->ioaddr1 + 1;
                 brdp->iostatus = brdp->ioaddr1 + 1;
                 status = inb(brdp->iostatus);
-                if ((status & ECH_IDBITMASK) != ECH_ID)
-                        return(-ENODEV);
+                if ((status & ECH_IDBITMASK) != ECH_ID) {
+                        retval = -ENODEV;
+                        goto err;
+                }
                 if ((brdp->irq < 0) || (brdp->irq > 15) ||
                     (stl_vecmap[brdp->irq] == (unsigned char) 0xff)) {
                         printk("STALLION: invalid irq=%d for brd=%d\n",
                                 brdp->irq, brdp->brdnr);
-                        return(-EINVAL);
+                        retval = -EINVAL;
+                        goto err;
                 }
                 status = ((brdp->ioaddr2 & ECH_ADDR2MASK) >> 1);
                 status |= (stl_vecmap[brdp->irq] << 1);
@@ -2162,13 +2201,16 @@ static int __init stl_initech(struct stlbrd *brdp)
                 brdp->ioctrl = brdp->ioaddr1 + 0x20;
                 brdp->iostatus = brdp->ioctrl;
                 status = inb(brdp->iostatus);
-                if ((status & ECH_IDBITMASK) != ECH_ID)
-                        return(-ENODEV);
+                if ((status & ECH_IDBITMASK) != ECH_ID) {
+                        retval = -ENODEV;
+                        goto err;
+                }
                 if ((brdp->irq < 0) || (brdp->irq > 15) ||
                     (stl_vecmap[brdp->irq] == (unsigned char) 0xff)) {
                         printk("STALLION: invalid irq=%d for brd=%d\n",
                                 brdp->irq, brdp->brdnr);
-                        return(-EINVAL);
+                        retval = -EINVAL;
+                        goto err;
                 }
                 outb(ECHMC_BRDRESET, brdp->ioctrl);
                 outb(ECHMC_INTENABLE, brdp->ioctrl);
@@ -2195,19 +2237,20 @@ static int __init stl_initech(struct stlbrd *brdp)
 
         default:
                 printk("STALLION: unknown board type=%d\n", brdp->brdtype);
-                return(-EINVAL);
-                break;
+                retval = -EINVAL;
+                goto err;
         }
 
 /*
  *      Check boards for possible IO address conflicts and return fail status 
  *      if an IO conflict found.
  */
+        retval = -EBUSY;
         if (!request_region(brdp->ioaddr1, brdp->iosize1, name)) {
                 printk(KERN_WARNING "STALLION: Warning, board %d I/O address "
                         "%x conflicts with another device\n", brdp->brdnr, 
                         brdp->ioaddr1);
-                return(-EBUSY);
+                goto err;
         }
         
         if (brdp->iosize2 > 0)
@@ -2218,8 +2261,7 @@ static int __init stl_initech(struct stlbrd *brdp)
                         printk(KERN_WARNING "STALLION: Warning, also "
                                 "releasing board %d I/O address %x \n", 
                                 brdp->brdnr, brdp->ioaddr1);
-                        release_region(brdp->ioaddr1, brdp->iosize1);
-                        return(-EBUSY);
+                        goto err_rel1;
                 }
 
 /*
@@ -2241,12 +2283,12 @@ static int __init stl_initech(struct stlbrd *brdp)
                 }
                 status = inb(ioaddr + ECH_PNLSTATUS);
                 if ((status & ECH_PNLIDMASK) != nxtid)
-                        break;
+                        goto err_fr;
                 panelp = kzalloc(sizeof(struct stlpanel), GFP_KERNEL);
                 if (!panelp) {
                         printk("STALLION: failed to allocate memory "
                                 "(size=%Zd)\n", sizeof(struct stlpanel));
-                        break;
+                        goto err_fr;
                 }
                 panelp->magic = STL_PANELMAGIC;
                 panelp->brdnr = brdp->brdnr;
@@ -2294,7 +2336,7 @@ static int __init stl_initech(struct stlbrd *brdp)
                 brdp->panels[panelnr++] = panelp;
                 if ((brdp->brdtype != BRD_ECHPCI) &&
                     (ioaddr >= (brdp->ioaddr2 + brdp->iosize2)))
-                        break;
+                        goto err_fr;
         }
 
         brdp->nrpanels = panelnr;
@@ -2306,12 +2348,19 @@ static int __init stl_initech(struct stlbrd *brdp)
         if (request_irq(brdp->irq, stl_intr, IRQF_SHARED, name, brdp) != 0) {
                 printk("STALLION: failed to register interrupt "
                     "routine for %s irq=%d\n", name, brdp->irq);
-                i = -ENODEV;
-        } else {
-                i = 0;
+                retval = -ENODEV;
+                goto err_fr;
         }
 
-        return(i);
+        return 0;
+err_fr:
+        stl_cleanup_panels(brdp);
+        if (brdp->iosize2 > 0)
+                release_region(brdp->ioaddr2, brdp->iosize2);
+err_rel1:
+        release_region(brdp->ioaddr1, brdp->iosize1);
+err:
+        return retval;
 }
 
 /*****************************************************************************/
@@ -2325,25 +2374,30 @@ static int __init stl_initech(struct stlbrd *brdp)
 
 static int __init stl_brdinit(struct stlbrd *brdp)
 {
-        int     i;
+        int i, retval;
 
         pr_debug("stl_brdinit(brdp=%p)\n", brdp);
 
         switch (brdp->brdtype) {
         case BRD_EASYIO:
         case BRD_EASYIOPCI:
-                stl_initeio(brdp);
+                retval = stl_initeio(brdp);
+                if (retval)
+                        goto err;
                 break;
         case BRD_ECH:
         case BRD_ECHMC:
         case BRD_ECHPCI:
         case BRD_ECH64PCI:
-                stl_initech(brdp);
+                retval = stl_initech(brdp);
+                if (retval)
+                        goto err;
                 break;
         default:
                 printk("STALLION: board=%d is unknown board type=%d\n",
                         brdp->brdnr, brdp->brdtype);
-                return(ENODEV);
+                retval = -ENODEV;
+                goto err;
         }
 
         stl_brds[brdp->brdnr] = brdp;
@@ -2351,7 +2405,7 @@ static int __init stl_brdinit(struct stlbrd *brdp)
                 printk("STALLION: %s board not found, board=%d io=%x irq=%d\n",
                         stl_brdnames[brdp->brdtype], brdp->brdnr,
                         brdp->ioaddr1, brdp->irq);
-                return(ENODEV);
+                goto err_free;
         }
 
         for (i = 0; (i < STL_MAXPANELS); i++)
@@ -2362,7 +2416,20 @@ static int __init stl_brdinit(struct stlbrd *brdp)
                 "nrpanels=%d nrports=%d\n", stl_brdnames[brdp->brdtype],
                 brdp->brdnr, brdp->ioaddr1, brdp->irq, brdp->nrpanels,
                 brdp->nrports);
-        return(0);
+
+        return 0;
+err_free:
+        free_irq(brdp->irq, brdp);
+
+        stl_cleanup_panels(brdp);
+
+        release_region(brdp->ioaddr1, brdp->iosize1);
+        if (brdp->iosize2 > 0)
+                release_region(brdp->ioaddr2, brdp->iosize2);
+
+        stl_brds[brdp->brdnr] = NULL;
+err:
+        return retval;
 }
 
 /*****************************************************************************/
@@ -2385,29 +2452,6 @@ static int __init stl_getbrdnr(void)
         return(-1);
 }
 
-static void stl_cleanup_panels(struct stlbrd *brdp)
-{
-        struct stlpanel *panelp;
-        struct stlport *portp;
-        unsigned int j, k;
-
-        for (j = 0; j < STL_MAXPANELS; j++) {
-                panelp = brdp->panels[j];
-                if (panelp == NULL)
-                        continue;
-                for (k = 0; k < STL_PORTSPERPANEL; k++) {
-                        portp = panelp->ports[k];
-                        if (portp == NULL)
-                                continue;
-                        if (portp->tty != NULL)
-                                stl_hangup(portp->tty);
-                        kfree(portp->tx.buf);
-                        kfree(portp);
-                }
-                kfree(panelp);
-        }
-}
-
 /*****************************************************************************/
 /*
  *      We have a Stallion board. Allocate a board structure and
@@ -2420,21 +2464,27 @@ static int __devinit stl_pciprobe(struct pci_dev *pdev,
 {
         struct stlbrd *brdp;
         unsigned int brdtype = ent->driver_data;
+        int retval = -ENODEV;
 
         if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE)
-                return -ENODEV;
+                goto err;
 
         dev_info(&pdev->dev, "please, report this to LKML: %x/%x/%x\n",
                         pdev->vendor, pdev->device, pdev->class);
 
-        if (pci_enable_device(pdev))
-                return(-EIO);
-        if ((brdp = stl_allocbrd()) == NULL)
-                return(-ENOMEM);
-        if ((brdp->brdnr = stl_getbrdnr()) < 0) {
+        retval = pci_enable_device(pdev);
+        if (retval)
+                goto err;
+        brdp = stl_allocbrd();
+        if (brdp == NULL) {
+                retval = -ENOMEM;
+                goto err;
+        }
+        brdp->brdnr = stl_getbrdnr();
+        if (brdp->brdnr < 0) {
                 dev_err(&pdev->dev, "too many boards found, "
                         "maximum supported %d\n", STL_MAXBRDS);
-                return(0);
+                goto err_fr;
         }
         brdp->brdtype = brdtype;
 
@@ -2461,11 +2511,17 @@ static int __devinit stl_pciprobe(struct pci_dev *pdev,
         }
 
         brdp->irq = pdev->irq;
-        stl_brdinit(brdp);
+        retval = stl_brdinit(brdp);
+        if (retval)
+                goto err_fr;
 
         pci_set_drvdata(pdev, brdp);
 
-        return(0);
+        return 0;
+err_fr:
+        kfree(brdp);
+err:
+        return retval;
 }
 
 static void __devexit stl_pciremove(struct pci_dev *pdev)
@@ -2528,7 +2584,8 @@ static int __init stl_initbrds(void)
                 brdp->ioaddr2 = confp->ioaddr2;
                 brdp->irq = confp->irq;
                 brdp->irqtype = confp->irqtype;
-                stl_brdinit(brdp);
+                if (stl_brdinit(brdp))
+                        kfree(brdp);
         }
 
 /*