summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJeff Garzik <jgarzik@pobox.com>2005-10-30 23:31:48 -0500
committerJeff Garzik <jgarzik@pobox.com>2005-10-30 23:31:48 -0500
commit005a5a06a6dd13a0ca3f2c6a0218e8d94ed36d8a (patch)
tree5b270817df4bc9661365d789d51c04f3774c3ddd
parente533825447dcb60a82b7cc9d73d06423c849b9a2 (diff)
[libata] locking rewrite (== fix)
A lot of power packed into a little patch. This change eliminates the sharing between our controller-wide spinlock and the SCSI core's Scsi_Host lock. As the locking in libata was already highly compartmentalized, always referencing our own lock, and never scsi_host::host_lock. As a side effect, this change eliminates a deadlock from calling scsi_finish_command() while inside our spinlock.
-rw-r--r--drivers/scsi/libata-core.c2
-rw-r--r--drivers/scsi/libata-scsi.c9
2 files changed, 8 insertions, 3 deletions
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index a17e12032f65..ff18fa7044c5 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4089,8 +4089,6 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host,
host->unique_id = ata_unique_id++;
host->max_cmd_len = 12;
- scsi_assign_lock(host, &host_set->lock);
-
ap->flags = ATA_FLAG_PORT_DISABLED;
ap->id = host->unique_id;
ap->host = host;
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 1e3792f86fcf..248baae96486 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -39,6 +39,7 @@
#include <scsi/scsi.h>
#include "scsi.h"
#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
#include <linux/libata.h>
#include <linux/hdreg.h>
#include <asm/uaccess.h>
@@ -2405,8 +2406,12 @@ int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
struct ata_port *ap;
struct ata_device *dev;
struct scsi_device *scsidev = cmd->device;
+ struct Scsi_Host *shost = scsidev->host;
- ap = (struct ata_port *) &scsidev->host->hostdata[0];
+ ap = (struct ata_port *) &shost->hostdata[0];
+
+ spin_unlock(shost->host_lock);
+ spin_lock(&ap->host_set->lock);
ata_scsi_dump_cdb(ap, cmd);
@@ -2429,6 +2434,8 @@ int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
ata_scsi_translate(ap, dev, cmd, done, atapi_xlat);
out_unlock:
+ spin_unlock(&ap->host_set->lock);
+ spin_lock(shost->host_lock);
return 0;
}