block/swim3: Locking fixes

The old PowerMac swim3 driver has some "interesting" locking issues,
using a private lock and failing to lock the queue before completing
requests, which triggered WARN_ONs among others.

This rips out the private lock, makes everything operate under the
block queue lock, and generally makes things simpler.

We used to also share a queue between the two possible instances which
was problematic since we might pick the wrong controller in some cases,
so make the queue and the current request per-instance and use
queuedata to point to our private data which is a lot cleaner.

We still share the queue lock but then, it's nearly impossible to actually
use 2 swim3's simultaneously: one would need to have a Wallstreet
PowerBook, the only machine afaik with two of these on the motherboard,
and populate both hotswap bays with a floppy drive (the machine ships
only with one), so nobody cares...

While at it, add a little fix to clear up stale interrupts when loading
the driver or plugging a floppy drive in a bay.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 215 insertions, 147 deletions

diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index ae3e167e17ad..89ddab127e33 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -16,6 +16,8 @@
  * handle GCR disks
  */
 
+#undef DEBUG
+
 #include <linux/stddef.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
@@ -36,13 +38,11 @@
 #include <asm/machdep.h>
 #include <asm/pmac_feature.h>
 
-static DEFINE_MUTEX(swim3_mutex);
-static struct request_queue *swim3_queue;
-static struct gendisk *disks[2];
-static struct request *fd_req;
-
 #define MAX_FLOPPIES    2
 
+static DEFINE_MUTEX(swim3_mutex);
+static struct gendisk *disks[MAX_FLOPPIES];
+
 enum swim_state {
         idle,
         locating,
@@ -177,7 +177,6 @@ struct swim3 {
 
 struct floppy_state {
         enum swim_state state;
-        spinlock_t lock;
         struct swim3 __iomem *swim3;    /* hardware registers */
         struct dbdma_regs __iomem *dma; /* DMA controller registers */
         int     swim3_intr;     /* interrupt number for SWIM3 */
@@ -204,8 +203,20 @@ struct floppy_state {
         int     wanted;
         struct macio_dev *mdev;
         char    dbdma_cmd_space[5 * sizeof(struct dbdma_cmd)];
+        int     index;
+        struct request *cur_req;
 };
 
+#define swim3_err(fmt, arg...)  dev_err(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#define swim3_warn(fmt, arg...) dev_warn(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#define swim3_info(fmt, arg...) dev_info(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+
+#ifdef DEBUG
+#define swim3_dbg(fmt, arg...)  dev_dbg(&fs->mdev->ofdev.dev, "[fd%d] " fmt, fs->index, arg)
+#else
+#define swim3_dbg(fmt, arg...)  do { } while(0)
+#endif
+
 static struct floppy_state floppy_states[MAX_FLOPPIES];
 static int floppy_count = 0;
 static DEFINE_SPINLOCK(swim3_lock);
@@ -224,17 +235,8 @@ static unsigned short write_postamble[] = {
         0, 0, 0, 0, 0, 0
 };
 
-static void swim3_select(struct floppy_state *fs, int sel);
-static void swim3_action(struct floppy_state *fs, int action);
-static int swim3_readbit(struct floppy_state *fs, int bit);
-static void do_fd_request(struct request_queue * q);
-static void start_request(struct floppy_state *fs);
-static void set_timeout(struct floppy_state *fs, int nticks,
-                        void (*proc)(unsigned long));
-static void scan_track(struct floppy_state *fs);
 static void seek_track(struct floppy_state *fs, int n);
 static void init_dma(struct dbdma_cmd *cp, int cmd, void *buf, int count);
-static void setup_transfer(struct floppy_state *fs);
 static void act(struct floppy_state *fs);
 static void scan_timeout(unsigned long data);
 static void seek_timeout(unsigned long data);
@@ -254,18 +256,21 @@ static unsigned int floppy_check_events(struct gendisk *disk,
                                         unsigned int clearing);
 static int floppy_revalidate(struct gendisk *disk);
 
-static bool swim3_end_request(int err, unsigned int nr_bytes)
+static bool swim3_end_request(struct floppy_state *fs, int err, unsigned int nr_bytes)
 {
-        if (__blk_end_request(fd_req, err, nr_bytes))
-                return true;
+        struct request *req = fs->cur_req;
+        int rc;
 
-        fd_req = NULL;
-        return false;
-}
+        swim3_dbg("  end request, err=%d nr_bytes=%d, cur_req=%p\n",
+                  err, nr_bytes, req);
 
-static bool swim3_end_request_cur(int err)
-{
-        return swim3_end_request(err, blk_rq_cur_bytes(fd_req));
+        if (err)
+                nr_bytes = blk_rq_cur_bytes(req);
+        rc = __blk_end_request(req, err, nr_bytes);
+        if (rc)
+                return true;
+        fs->cur_req = NULL;
+        return false;
 }
 
 static void swim3_select(struct floppy_state *fs, int sel)
@@ -303,50 +308,53 @@ static int swim3_readbit(struct floppy_state *fs, int bit)
         return (stat & DATA) == 0;
 }
 
-static void do_fd_request(struct request_queue * q)
-{
-        int i;
-
-        for(i=0; i<floppy_count; i++) {
-                struct floppy_state *fs = &floppy_states[i];
-                if (fs->mdev->media_bay &&
-                    check_media_bay(fs->mdev->media_bay) != MB_FD)
-                        continue;
-                start_request(fs);
-        }
-}
-
 static void start_request(struct floppy_state *fs)
 {
         struct request *req;
         unsigned long x;
 
+        swim3_dbg("start request, initial state=%d\n", fs->state);
+
         if (fs->state == idle && fs->wanted) {
                 fs->state = available;
                 wake_up(&fs->wait);
                 return;
         }
         while (fs->state == idle) {
-                if (!fd_req) {
-                        fd_req = blk_fetch_request(swim3_queue);
-                        if (!fd_req)
+                swim3_dbg("start request, idle loop, cur_req=%p\n", fs->cur_req);
+                if (!fs->cur_req) {
+                        fs->cur_req = blk_fetch_request(disks[fs->index]->queue);
+                        swim3_dbg("  fetched request %p\n", fs->cur_req);
+                        if (!fs->cur_req)
                                 break;
                 }
-                req = fd_req;
-#if 0
-                printk("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%u buf=%p\n",
-                       req->rq_disk->disk_name, req->cmd,
-                       (long)blk_rq_pos(req), blk_rq_sectors(req), req->buffer);
-                printk("           errors=%d current_nr_sectors=%u\n",
-                       req->errors, blk_rq_cur_sectors(req));
+                req = fs->cur_req;
+
+                if (fs->mdev->media_bay &&
+                    check_media_bay(fs->mdev->media_bay) != MB_FD) {
+                        swim3_dbg("%s", "  media bay absent, dropping req\n");
+                        swim3_end_request(fs, -ENODEV, 0);
+                        continue;
+                }
+
+#if 0 /* This is really too verbose */
+                swim3_dbg("do_fd_req: dev=%s cmd=%d sec=%ld nr_sec=%u buf=%p\n",
+                          req->rq_disk->disk_name, req->cmd,
+                          (long)blk_rq_pos(req), blk_rq_sectors(req),
+                          req->buffer);
+                swim3_dbg("           errors=%d current_nr_sectors=%u\n",
+                          req->errors, blk_rq_cur_sectors(req));
 #endif
 
                 if (blk_rq_pos(req) >= fs->total_secs) {
-                        swim3_end_request_cur(-EIO);
+                        swim3_dbg("  pos out of bounds (%ld, max is %ld)\n",
+                                  (long)blk_rq_pos(req), (long)fs->total_secs);
+                        swim3_end_request(fs, -EIO, 0);
                         continue;
                 }
                 if (fs->ejected) {
-                        swim3_end_request_cur(-EIO);
+                        swim3_dbg("%s", "  disk ejected\n");
+                        swim3_end_request(fs, -EIO, 0);
                         continue;
                 }
 
@@ -354,7 +362,8 @@ static void start_request(struct floppy_state *fs)
                         if (fs->write_prot < 0)
                                 fs->write_prot = swim3_readbit(fs, WRITE_PROT);
                         if (fs->write_prot) {
-                                swim3_end_request_cur(-EIO);
+                                swim3_dbg("%s", "  try to write, disk write protected\n");
+                                swim3_end_request(fs, -EIO, 0);
                                 continue;
                         }
                 }
@@ -369,7 +378,6 @@ static void start_request(struct floppy_state *fs)
                 x = ((long)blk_rq_pos(req)) % fs->secpercyl;
                 fs->head = x / fs->secpertrack;
                 fs->req_sector = x % fs->secpertrack + 1;
-                fd_req = req;
                 fs->state = do_transfer;
                 fs->retries = 0;
 
@@ -377,12 +385,14 @@ static void start_request(struct floppy_state *fs)
         }
 }
 
+static void do_fd_request(struct request_queue * q)
+{
+        start_request(q->queuedata);
+}
+
 static void set_timeout(struct floppy_state *fs, int nticks,
                         void (*proc)(unsigned long))
 {
-        unsigned long flags;
-
-        spin_lock_irqsave(&fs->lock, flags);
         if (fs->timeout_pending)
                 del_timer(&fs->timeout);
         fs->timeout.expires = jiffies + nticks;
@@ -390,7 +400,6 @@ static void set_timeout(struct floppy_state *fs, int nticks,
         fs->timeout.data = (unsigned long) fs;
         add_timer(&fs->timeout);
         fs->timeout_pending = 1;
-        spin_unlock_irqrestore(&fs->lock, flags);
 }
 
 static inline void scan_track(struct floppy_state *fs)
@@ -442,40 +451,45 @@ static inline void setup_transfer(struct floppy_state *fs)
         struct swim3 __iomem *sw = fs->swim3;
         struct dbdma_cmd *cp = fs->dma_cmd;
         struct dbdma_regs __iomem *dr = fs->dma;
+        struct request *req = fs->cur_req;
 
-        if (blk_rq_cur_sectors(fd_req) <= 0) {
-                printk(KERN_ERR "swim3: transfer 0 sectors?\n");
+        if (blk_rq_cur_sectors(req) <= 0) {
+                swim3_warn("%s", "Transfer 0 sectors ?\n");
                 return;
         }
-        if (rq_data_dir(fd_req) == WRITE)
+        if (rq_data_dir(req) == WRITE)
                 n = 1;
         else {
                 n = fs->secpertrack - fs->req_sector + 1;
-                if (n > blk_rq_cur_sectors(fd_req))
-                        n = blk_rq_cur_sectors(fd_req);
+                if (n > blk_rq_cur_sectors(req))
+                        n = blk_rq_cur_sectors(req);
         }
+
+        swim3_dbg("  setup xfer at sect %d (of %d) head %d for %d\n",
+                  fs->req_sector, fs->secpertrack, fs->head, n);
+
         fs->scount = n;
         swim3_select(fs, fs->head? READ_DATA_1: READ_DATA_0);
         out_8(&sw->sector, fs->req_sector);
         out_8(&sw->nsect, n);
         out_8(&sw->gap3, 0);
         out_le32(&dr->cmdptr, virt_to_bus(cp));
-        if (rq_data_dir(fd_req) == WRITE) {
+        if (rq_data_dir(req) == WRITE) {
                 /* Set up 3 dma commands: write preamble, data, postamble */
                 init_dma(cp, OUTPUT_MORE, write_preamble, sizeof(write_preamble));
                 ++cp;
-                init_dma(cp, OUTPUT_MORE, fd_req->buffer, 512);
+                init_dma(cp, OUTPUT_MORE, req->buffer, 512);
                 ++cp;
                 init_dma(cp, OUTPUT_LAST, write_postamble, sizeof(write_postamble));
         } else {
-                init_dma(cp, INPUT_LAST, fd_req->buffer, n * 512);
+                init_dma(cp, INPUT_LAST, req->buffer, n * 512);
         }
         ++cp;
         out_le16(&cp->command, DBDMA_STOP);
         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
         in_8(&sw->error);
         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
-        if (rq_data_dir(fd_req) == WRITE)
+        if (rq_data_dir(req) == WRITE)
                 out_8(&sw->control_bis, WRITE_SECTORS);
         in_8(&sw->intr);
         out_le32(&dr->control, (RUN << 16) | RUN);
@@ -488,12 +502,16 @@ static inline void setup_transfer(struct floppy_state *fs)
 static void act(struct floppy_state *fs)
 {
         for (;;) {
+                swim3_dbg("  act loop, state=%d, req_cyl=%d, cur_cyl=%d\n",
+                          fs->state, fs->req_cyl, fs->cur_cyl);
+
                 switch (fs->state) {
                 case idle:
                         return;         /* XXX shouldn't get here */
 
                 case locating:
                         if (swim3_readbit(fs, TRACK_ZERO)) {
+                                swim3_dbg("%s", "    locate track 0\n");
                                 fs->cur_cyl = 0;
                                 if (fs->req_cyl == 0)
                                         fs->state = do_transfer;
@@ -511,7 +529,7 @@ static void act(struct floppy_state *fs)
                                 break;
                         }
                         if (fs->req_cyl == fs->cur_cyl) {
-                                printk("whoops, seeking 0\n");
+                                swim3_warn("%s", "Whoops, seeking 0\n");
                                 fs->state = do_transfer;
                                 break;
                         }
@@ -527,7 +545,9 @@ static void act(struct floppy_state *fs)
                 case do_transfer:
                         if (fs->cur_cyl != fs->req_cyl) {
                                 if (fs->retries > 5) {
-                                        swim3_end_request_cur(-EIO);
+                                        swim3_err("Wrong cylinder in transfer, want: %d got %d\n",
+                                                  fs->req_cyl, fs->cur_cyl);
+                                        swim3_end_request(fs, -EIO, 0);
                                         fs->state = idle;
                                         return;
                                 }
@@ -542,7 +562,7 @@ static void act(struct floppy_state *fs)
                         return;
 
                 default:
-                        printk(KERN_ERR"swim3: unknown state %d\n", fs->state);
+                        swim3_err("Unknown state %d\n", fs->state);
                         return;
                 }
         }
@@ -552,59 +572,75 @@ static void scan_timeout(unsigned long data)
 {
         struct floppy_state *fs = (struct floppy_state *) data;
         struct swim3 __iomem *sw = fs->swim3;
+        unsigned long flags;
+
+        swim3_dbg("* scan timeout, state=%d\n", fs->state);
 
+        spin_lock_irqsave(&swim3_lock, flags);
         fs->timeout_pending = 0;
         out_8(&sw->control_bic, DO_ACTION | WRITE_SECTORS);
         out_8(&sw->select, RELAX);
         out_8(&sw->intr_enable, 0);
         fs->cur_cyl = -1;
         if (fs->retries > 5) {
-                swim3_end_request_cur(-EIO);
+                swim3_end_request(fs, -EIO, 0);
                 fs->state = idle;
                 start_request(fs);
         } else {
                 fs->state = jogging;
                 act(fs);
         }
+        spin_unlock_irqrestore(&swim3_lock, flags);
 }
 
 static void seek_timeout(unsigned long data)
 {
         struct floppy_state *fs = (struct floppy_state *) data;
         struct swim3 __iomem *sw = fs->swim3;
+        unsigned long flags;
+
+        swim3_dbg("* seek timeout, state=%d\n", fs->state);
 
+        spin_lock_irqsave(&swim3_lock, flags);
         fs->timeout_pending = 0;
         out_8(&sw->control_bic, DO_SEEK);
         out_8(&sw->select, RELAX);
         out_8(&sw->intr_enable, 0);
-        printk(KERN_ERR "swim3: seek timeout\n");
-        swim3_end_request_cur(-EIO);
+        swim3_err("%s", "Seek timeout\n");
+        swim3_end_request(fs, -EIO, 0);
         fs->state = idle;
         start_request(fs);
+        spin_unlock_irqrestore(&swim3_lock, flags);
 }
 
 static void settle_timeout(unsigned long data)
 {
         struct floppy_state *fs = (struct floppy_state *) data;
         struct swim3 __iomem *sw = fs->swim3;
+        unsigned long flags;
+
+        swim3_dbg("* settle timeout, state=%d\n", fs->state);
 
+        spin_lock_irqsave(&swim3_lock, flags);
         fs->timeout_pending = 0;
         if (swim3_readbit(fs, SEEK_COMPLETE)) {
                 out_8(&sw->select, RELAX);
                 fs->state = locating;
                 act(fs);
-                return;
+                goto unlock;
         }
         out_8(&sw->select, RELAX);
         if (fs->settle_time < 2*HZ) {
                 ++fs->settle_time;
                 set_timeout(fs, 1, settle_timeout);
-                return;
+                goto unlock;
         }
-        printk(KERN_ERR "swim3: seek settle timeout\n");
-        swim3_end_request_cur(-EIO);
+        swim3_err("%s", "Seek settle timeout\n");
+        swim3_end_request(fs, -EIO, 0);
         fs->state = idle;
         start_request(fs);
+ unlock:
+        spin_unlock_irqrestore(&swim3_lock, flags);
 }
 
 static void xfer_timeout(unsigned long data)
@@ -612,8 +648,12 @@ static void xfer_timeout(unsigned long data)
         struct floppy_state *fs = (struct floppy_state *) data;
         struct swim3 __iomem *sw = fs->swim3;
         struct dbdma_regs __iomem *dr = fs->dma;
+        unsigned long flags;
         int n;
 
+        swim3_dbg("* xfer timeout, state=%d\n", fs->state);
+
+        spin_lock_irqsave(&swim3_lock, flags);
         fs->timeout_pending = 0;
         out_le32(&dr->control, RUN << 16);
         /* We must wait a bit for dbdma to stop */
@@ -622,12 +662,13 @@ static void xfer_timeout(unsigned long data)
         out_8(&sw->intr_enable, 0);
         out_8(&sw->control_bic, WRITE_SECTORS | DO_ACTION);
         out_8(&sw->select, RELAX);
-        printk(KERN_ERR "swim3: timeout %sing sector %ld\n",
-               (rq_data_dir(fd_req)==WRITE? "writ": "read"),
-               (long)blk_rq_pos(fd_req));
-        swim3_end_request_cur(-EIO);
+        swim3_err("Timeout %sing sector %ld\n",
+               (rq_data_dir(fs->cur_req)==WRITE? "writ": "read"),
+               (long)blk_rq_pos(fs->cur_req));
+        swim3_end_request(fs, -EIO, 0);
         fs->state = idle;
         start_request(fs);
+        spin_unlock_irqrestore(&swim3_lock, flags);
 }
 
 static irqreturn_t swim3_interrupt(int irq, void *dev_id)
@@ -638,12 +679,17 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
         int stat, resid;
         struct dbdma_regs __iomem *dr;
         struct dbdma_cmd *cp;
+        unsigned long flags;
+        struct request *req = fs->cur_req;
+
+        swim3_dbg("* interrupt, state=%d\n", fs->state);
 
+        spin_lock_irqsave(&swim3_lock, flags);
         intr = in_8(&sw->intr);
         err = (intr & ERROR_INTR)? in_8(&sw->error): 0;
         if ((intr & ERROR_INTR) && fs->state != do_transfer)
-                printk(KERN_ERR "swim3_interrupt, state=%d, dir=%x, intr=%x, err=%x\n",
-                       fs->state, rq_data_dir(fd_req), intr, err);
+                swim3_err("Non-transfer error interrupt: state=%d, dir=%x, intr=%x, err=%x\n",
+                          fs->state, rq_data_dir(req), intr, err);
         switch (fs->state) {
         case locating:
                 if (intr & SEEN_SECTOR) {
@@ -653,10 +699,10 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
                         del_timer(&fs->timeout);
                         fs->timeout_pending = 0;
                         if (sw->ctrack == 0xff) {
-                                printk(KERN_ERR "swim3: seen sector but cyl=ff?\n");
+                                swim3_err("%s", "Seen sector but cyl=ff?\n");
                                 fs->cur_cyl = -1;
                                 if (fs->retries > 5) {
-                                        swim3_end_request_cur(-EIO);
+                                        swim3_end_request(fs, -EIO, 0);
                                         fs->state = idle;
                                         start_request(fs);
                                 } else {
@@ -668,8 +714,8 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
                         fs->cur_cyl = sw->ctrack;
                         fs->cur_sector = sw->csect;
                         if (fs->expect_cyl != -1 && fs->expect_cyl != fs->cur_cyl)
-                                printk(KERN_ERR "swim3: expected cyl %d, got %d\n",
-                                       fs->expect_cyl, fs->cur_cyl);
+                                swim3_err("Expected cyl %d, got %d\n",
+                                          fs->expect_cyl, fs->cur_cyl);
                         fs->state = do_transfer;
                         act(fs);
                 }
@@ -704,7 +750,7 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
                 fs->timeout_pending = 0;
                 dr = fs->dma;
                 cp = fs->dma_cmd;
-                if (rq_data_dir(fd_req) == WRITE)
+                if (rq_data_dir(req) == WRITE)
                         ++cp;
                 /*
                  * Check that the main data transfer has finished.
@@ -729,31 +775,32 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
                 if (intr & ERROR_INTR) {
                         n = fs->scount - 1 - resid / 512;
                         if (n > 0) {
-                                blk_update_request(fd_req, 0, n << 9);
+                                blk_update_request(req, 0, n << 9);
                                 fs->req_sector += n;
                         }
                         if (fs->retries < 5) {
                                 ++fs->retries;
                                 act(fs);
                         } else {
-                                printk("swim3: error %sing block %ld (err=%x)\n",
-                                       rq_data_dir(fd_req) == WRITE? "writ": "read",
-                                       (long)blk_rq_pos(fd_req), err);
-                                swim3_end_request_cur(-EIO);
+                                swim3_err("Error %sing block %ld (err=%x)\n",
+                                       rq_data_dir(req) == WRITE? "writ": "read",
+                                       (long)blk_rq_pos(req), err);
+                                swim3_end_request(fs, -EIO, 0);
                                 fs->state = idle;
                         }
                 } else {
                         if ((stat & ACTIVE) == 0 || resid != 0) {
                                 /* musta been an error */
-                                printk(KERN_ERR "swim3: fd dma: stat=%x resid=%d\n", stat, resid);
-                                printk(KERN_ERR "  state=%d, dir=%x, intr=%x, err=%x\n",
-                                       fs->state, rq_data_dir(fd_req), intr, err);
-                                swim3_end_request_cur(-EIO);
+                                swim3_err("fd dma error: stat=%x resid=%d\n", stat, resid);
+                                swim3_err("  state=%d, dir=%x, intr=%x, err=%x\n",
+                                          fs->state, rq_data_dir(req), intr, err);
+                                swim3_end_request(fs, -EIO, 0);
                                 fs->state = idle;
                                 start_request(fs);
                                 break;
                         }
-                        if (swim3_end_request(0, fs->scount << 9)) {
+                        fs->retries = 0;
+                        if (swim3_end_request(fs, 0, fs->scount << 9)) {
                                 fs->req_sector += fs->scount;
                                 if (fs->req_sector > fs->secpertrack) {
                                         fs->req_sector -= fs->secpertrack;
@@ -770,8 +817,9 @@ static irqreturn_t swim3_interrupt(int irq, void *dev_id)
                         start_request(fs);
                 break;
         default:
-                printk(KERN_ERR "swim3: don't know what to do in state %d\n", fs->state);
+                swim3_err("Don't know what to do in state %d\n", fs->state);
         }
+        spin_unlock_irqrestore(&swim3_lock, flags);
         return IRQ_HANDLED;
 }
 
@@ -781,26 +829,31 @@ static void fd_dma_interrupt(int irq, void *dev_id)
 }
 */
 
+/* Called under the mutex to grab exclusive access to a drive */
 static int grab_drive(struct floppy_state *fs, enum swim_state state,
                       int interruptible)
 {
         unsigned long flags;
 
-        spin_lock_irqsave(&fs->lock, flags);
-        if (fs->state != idle) {
+        swim3_dbg("%s", "-> grab drive\n");
+
+        spin_lock_irqsave(&swim3_lock, flags);
+        if (fs->state != idle && fs->state != available) {
                 ++fs->wanted;
                 while (fs->state != available) {
+                        spin_unlock_irqrestore(&swim3_lock, flags);
                         if (interruptible && signal_pending(current)) {
                                 --fs->wanted;
-                                spin_unlock_irqrestore(&fs->lock, flags);
                                 return -EINTR;
                         }
                         interruptible_sleep_on(&fs->wait);
+                        spin_lock_irqsave(&swim3_lock, flags);
                 }
                 --fs->wanted;
         }
         fs->state = state;
-        spin_unlock_irqrestore(&fs->lock, flags);
+        spin_unlock_irqrestore(&swim3_lock, flags);
+
         return 0;
 }
 
@@ -808,10 +861,12 @@ static void release_drive(struct floppy_state *fs)
 {
         unsigned long flags;
 
-        spin_lock_irqsave(&fs->lock, flags);
+        swim3_dbg("%s", "-> release drive\n");
+
+        spin_lock_irqsave(&swim3_lock, flags);
         fs->state = idle;
         start_request(fs);
-        spin_unlock_irqrestore(&fs->lock, flags);
+        spin_unlock_irqrestore(&swim3_lock, flags);
 }
 
 static int fd_eject(struct floppy_state *fs)
@@ -966,6 +1021,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 {
         struct floppy_state *fs = disk->private_data;
         struct swim3 __iomem *sw = fs->swim3;
+
         mutex_lock(&swim3_mutex);
         if (fs->ref_count > 0 && --fs->ref_count == 0) {
                 swim3_action(fs, MOTOR_OFF);
@@ -1031,30 +1087,48 @@ static const struct block_device_operations floppy_fops = {
         .revalidate_disk= floppy_revalidate,
 };
 
+static void swim3_mb_event(struct macio_dev* mdev, int mb_state)
+{
+        struct floppy_state *fs = macio_get_drvdata(mdev);
+        struct swim3 __iomem *sw = fs->swim3;
+
+        if (!fs)
+                return;
+        if (mb_state != MB_FD)
+                return;
+
+        /* Clear state */
+        out_8(&sw->intr_enable, 0);
+        in_8(&sw->intr);
+        in_8(&sw->error);
+}
+
 static int swim3_add_device(struct macio_dev *mdev, int index)
 {
         struct device_node *swim = mdev->ofdev.dev.of_node;
         struct floppy_state *fs = &floppy_states[index];
         int rc = -EBUSY;
 
+        /* Do this first for message macros */
+        memset(fs, 0, sizeof(*fs));
+        fs->mdev = mdev;
+        fs->index = index;
+
         /* Check & Request resources */
         if (macio_resource_count(mdev) < 2) {
-                printk(KERN_WARNING "ifd%d: no address for %s\n",
-                       index, swim->full_name);
+                swim3_err("%s", "No address in device-tree\n");
                 return -ENXIO;
         }
-        if (macio_irq_count(mdev) < 2) {
-                printk(KERN_WARNING "fd%d: no intrs for device %s\n",
-                        index, swim->full_name);
+        if (macio_irq_count(mdev) < 1) {
+                swim3_err("%s", "No interrupt in device-tree\n");
+                return -ENXIO;
         }
         if (macio_request_resource(mdev, 0, "swim3 (mmio)")) {
-                printk(KERN_ERR "fd%d: can't request mmio resource for %s\n",
-                       index, swim->full_name);
+                swim3_err("%s", "Can't request mmio resource\n");
                 return -EBUSY;
         }
         if (macio_request_resource(mdev, 1, "swim3 (dma)")) {
-                printk(KERN_ERR "fd%d: can't request dma resource for %s\n",
-                       index, swim->full_name);
+                swim3_err("%s", "Can't request dma resource\n");
                 macio_release_resource(mdev, 0);
                 return -EBUSY;
         }
@@ -1063,22 +1137,18 @@ static int swim3_add_device(struct macio_dev *mdev, int index)
         if (mdev->media_bay == NULL)
                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 1);
         
-        memset(fs, 0, sizeof(*fs));
-        spin_lock_init(&fs->lock);
         fs->state = idle;
         fs->swim3 = (struct swim3 __iomem *)
                 ioremap(macio_resource_start(mdev, 0), 0x200);
         if (fs->swim3 == NULL) {
-                printk("fd%d: couldn't map registers for %s\n",
-                       index, swim->full_name);
+                swim3_err("%s", "Couldn't map mmio registers\n");
                 rc = -ENOMEM;
                 goto out_release;
         }
         fs->dma = (struct dbdma_regs __iomem *)
                 ioremap(macio_resource_start(mdev, 1), 0x200);
         if (fs->dma == NULL) {
-                printk("fd%d: couldn't map DMA for %s\n",
-                       index, swim->full_name);
+                swim3_err("%s", "Couldn't map dma registers\n");
                 iounmap(fs->swim3);
                 rc = -ENOMEM;
                 goto out_release;
@@ -1090,31 +1160,25 @@ static int swim3_add_device(struct macio_dev *mdev, int index)
         fs->secpercyl = 36;
         fs->secpertrack = 18;
         fs->total_secs = 2880;
-        fs->mdev = mdev;
         init_waitqueue_head(&fs->wait);
 
         fs->dma_cmd = (struct dbdma_cmd *) DBDMA_ALIGN(fs->dbdma_cmd_space);
         memset(fs->dma_cmd, 0, 2 * sizeof(struct dbdma_cmd));
         st_le16(&fs->dma_cmd[1].command, DBDMA_STOP);
 
+        if (mdev->media_bay == NULL || check_media_bay(mdev->media_bay) == MB_FD)
+                swim3_mb_event(mdev, MB_FD);
+
         if (request_irq(fs->swim3_intr, swim3_interrupt, 0, "SWIM3", fs)) {
-                printk(KERN_ERR "fd%d: couldn't request irq %d for %s\n",
-                       index, fs->swim3_intr, swim->full_name);
+                swim3_err("%s", "Couldn't request interrupt\n");
                 pmac_call_feature(PMAC_FTR_SWIM3_ENABLE, swim, 0, 0);
                 goto out_unmap;
                 return -EBUSY;
         }
-/*
-        if (request_irq(fs->dma_intr, fd_dma_interrupt, 0, "SWIM3-dma", fs)) {
-                printk(KERN_ERR "Couldn't get irq %d for SWIM3 DMA",
-                       fs->dma_intr);
-                return -EBUSY;
-        }
-*/
 
         init_timer(&fs->timeout);
 
-        printk(KERN_INFO "fd%d: SWIM3 floppy controller %s\n", floppy_count,
+        swim3_info("SWIM3 floppy controller %s\n",
                 mdev->media_bay ? "in media bay" : "");
 
         return 0;
@@ -1132,41 +1196,42 @@ static int swim3_add_device(struct macio_dev *mdev, int index)
 
 static int __devinit swim3_attach(struct macio_dev *mdev, const struct of_device_id *match)
 {
-        int i, rc;
         struct gendisk *disk;
+        int index, rc;
+
+        index = floppy_count++;
+        if (index >= MAX_FLOPPIES)
+                return -ENXIO;
 
         /* Add the drive */
-        rc = swim3_add_device(mdev, floppy_count);
+        rc = swim3_add_device(mdev, index);
         if (rc)
                 return rc;
+        /* Now register that disk. Same comment about failure handling */
+        disk = disks[index] = alloc_disk(1);
+        if (disk == NULL)
+                return -ENOMEM;
+        disk->queue = blk_init_queue(do_fd_request, &swim3_lock);
+        if (disk->queue == NULL) {
+                put_disk(disk);
+                return -ENOMEM;
+        }
+        disk->queue->queuedata = &floppy_states[index];
 
-        /* Now create the queue if not there yet */
-        if (swim3_queue == NULL) {
+        if (index == 0) {
                 /* If we failed, there isn't much we can do as the driver is still
                  * too dumb to remove the device, just bail out
                  */
                 if (register_blkdev(FLOPPY_MAJOR, "fd"))
                         return 0;
-                swim3_queue = blk_init_queue(do_fd_request, &swim3_lock);
-                if (swim3_queue == NULL) {
-                        unregister_blkdev(FLOPPY_MAJOR, "fd");
-                        return 0;
-                }
         }
 
-        /* Now register that disk. Same comment about failure handling */
-        i = floppy_count++;
-        disk = disks[i] = alloc_disk(1);
-        if (disk == NULL)
-                return 0;
-
         disk->major = FLOPPY_MAJOR;
-        disk->first_minor = i;
+        disk->first_minor = index;
         disk->fops = &floppy_fops;
-        disk->private_data = &floppy_states[i];
-        disk->queue = swim3_queue;
+        disk->private_data = &floppy_states[index];
         disk->flags |= GENHD_FL_REMOVABLE;
-        sprintf(disk->disk_name, "fd%d", i);
+        sprintf(disk->disk_name, "fd%d", index);
         set_capacity(disk, 2880);
         add_disk(disk);
 
@@ -1194,6 +1259,9 @@ static struct macio_driver swim3_driver =
                 .of_match_table = swim3_match,
         },
         .probe          = swim3_attach,
+#ifdef CONFIG_PMAC_MEDIABAY
+        .mediabay_event = swim3_mb_event,
+#endif
 #if 0
         .suspend        = swim3_suspend,
         .resume         = swim3_resume,