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Date: Fri, 6 Feb 2009 10:57:06 -0700
From: Bjorn Helgaas <bjorn.helgaas@...com>
To: Philippe De Muyter <phdm@...qel.be>
Cc: Andrew Morton <akpm@...ux-foundation.org>,
linux-kernel@...r.kernel.org, hancockrwd@...il.com, abelay@....edu,
lenb@...nel.org, stable@...nel.org
Subject: Re: [PATCH] floppy: release only the ports we actually requested
On Friday 06 February 2009 09:20:13 am Bjorn Helgaas wrote:
> On Friday 06 February 2009 01:55:01 am Philippe De Muyter wrote:
> > Bjorn, Andrew,
> >
> > --
> >
> > With the last floppy patch, the floppy driver requests only the ports that
> > it really uses, but the code contains yet places where it releases those
> > unrequested ports. I don't know if it is harmfull, but I think it is cleaner
> > that the parameters of the release_region calls match the request_region ones.
>
> Doh! Boy, do I feel stupid. I doubt this is in any git trees yet,
> so I'll combine the two patches and send a cleaner one.
Philippe, can you give this a once-over? I can compile it, but I don't
have a machine with a floppy drive handy to test it. Since you pointed
out all the places I forgot to change, I went ahead and factored out
the request/release stuff so they're all in one place now.
Bjorn
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index cf29cc4..c2b3db4 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -558,6 +558,8 @@ static void process_fd_request(void);
static void recalibrate_floppy(void);
static void floppy_shutdown(unsigned long);
+static int floppy_request_regions(int);
+static void floppy_release_regions(int);
static int floppy_grab_irq_and_dma(void);
static void floppy_release_irq_and_dma(void);
@@ -4274,8 +4276,7 @@ static int __init floppy_init(void)
FDCS->rawcmd = 2;
if (user_reset_fdc(-1, FD_RESET_ALWAYS, 0)) {
/* free ioports reserved by floppy_grab_irq_and_dma() */
- release_region(FDCS->address + 2, 4);
- release_region(FDCS->address + 7, 1);
+ floppy_release_regions(fdc);
FDCS->address = -1;
FDCS->version = FDC_NONE;
continue;
@@ -4284,8 +4285,7 @@ static int __init floppy_init(void)
FDCS->version = get_fdc_version();
if (FDCS->version == FDC_NONE) {
/* free ioports reserved by floppy_grab_irq_and_dma() */
- release_region(FDCS->address + 2, 4);
- release_region(FDCS->address + 7, 1);
+ floppy_release_regions(fdc);
FDCS->address = -1;
continue;
}
@@ -4358,6 +4358,38 @@ out_put_disk:
static DEFINE_SPINLOCK(floppy_usage_lock);
+static int floppy_request_regions(int fdc)
+{
+ if (!request_region(FDCS->address + 2, 1, "floppy")) {
+ DPRINT("Floppy io-port 0x%04lx in use\n", FDCS->address + 2);
+ return -EBUSY;
+ }
+ if (!request_region(FDCS->address + 4, 2, "floppy")) {
+ DPRINT("Floppy io-port 0x%04lx in use\n", FDCS->address + 4);
+ goto cleanup1;
+ }
+ if (!request_region(FDCS->address + 7, 1, "floppy DIR")) {
+ DPRINT("Floppy io-port 0x%04lx in use\n", FDCS->address + 7);
+ goto cleanup2;
+ }
+ /* address + 6 is reserved, and may be taken by IDE.
+ * Unfortunately, Adaptec doesn't know this :-(, */
+ return 0;
+
+cleanup2:
+ release_region(FDCS->address + 4, 2);
+cleanup1:
+ release_region(FDCS->address + 2, 1);
+ return -EBUSY;
+}
+
+static void floppy_release_regions(int fdc)
+{
+ release_region(FDCS->address + 2, 1);
+ release_region(FDCS->address + 4, 2);
+ release_region(FDCS->address + 7, 1);
+}
+
static int floppy_grab_irq_and_dma(void)
{
unsigned long flags;
@@ -4399,18 +4431,8 @@ static int floppy_grab_irq_and_dma(void)
for (fdc = 0; fdc < N_FDC; fdc++) {
if (FDCS->address != -1) {
- if (!request_region(FDCS->address + 2, 4, "floppy")) {
- DPRINT("Floppy io-port 0x%04lx in use\n",
- FDCS->address + 2);
- goto cleanup1;
- }
- if (!request_region(FDCS->address + 7, 1, "floppy DIR")) {
- DPRINT("Floppy io-port 0x%04lx in use\n",
- FDCS->address + 7);
- goto cleanup2;
- }
- /* address + 6 is reserved, and may be taken by IDE.
- * Unfortunately, Adaptec doesn't know this :-(, */
+ if (floppy_request_regions(fdc))
+ goto cleanup;
}
}
for (fdc = 0; fdc < N_FDC; fdc++) {
@@ -4432,15 +4454,11 @@ static int floppy_grab_irq_and_dma(void)
fdc = 0;
irqdma_allocated = 1;
return 0;
-cleanup2:
- release_region(FDCS->address + 2, 4);
-cleanup1:
+cleanup:
fd_free_irq();
fd_free_dma();
- while (--fdc >= 0) {
- release_region(FDCS->address + 2, 4);
- release_region(FDCS->address + 7, 1);
- }
+ while (--fdc >= 0)
+ floppy_release_regions(fdc);
spin_lock_irqsave(&floppy_usage_lock, flags);
usage_count--;
spin_unlock_irqrestore(&floppy_usage_lock, flags);
@@ -4502,8 +4520,7 @@ static void floppy_release_irq_and_dma(void)
old_fdc = fdc;
for (fdc = 0; fdc < N_FDC; fdc++)
if (FDCS->address != -1) {
- release_region(FDCS->address + 2, 4);
- release_region(FDCS->address + 7, 1);
+ floppy_release_regions(fdc);
}
fdc = old_fdc;
}
--
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