libata: make ata_print_id atomic

This variable is incremented from multiple contexts (module_init via
libata-lldds and the libsas discovery thread).  Make it atomic to head
off any chance of libsas and libata creating duplicate ids.

Acked-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index ea8444e4d60738c7bf8734d60e4616205695cb5f..bd79c8b6edacc092317eef1be7db85e1b68cf0cf 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -97,7 +97,7 @@ static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
 static void ata_dev_xfermask(struct ata_device *dev);
 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
 
-unsigned int ata_print_id = 1;
+atomic_t ata_print_id = ATOMIC_INIT(1);
 
 struct ata_force_param {
        const char      *name;
@@ -6031,7 +6031,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
 
        /* give ports names and add SCSI hosts */
        for (i = 0; i < host->n_ports; i++)
-               host->ports[i]->print_id = ata_print_id++;
+               host->ports[i]->print_id = atomic_inc_return(&ata_print_id);
 
 
        /* Create associated sysfs transport objects  */

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 1ee00c8b5b0495674c30237f2be672dee81ee928..93dabdcd2cbe3712191f4ae05c0720a1bf42549d 100644 (file)
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3843,7 +3843,7 @@ int ata_sas_async_port_init(struct ata_port *ap)
        int rc = ap->ops->port_start(ap);
 
        if (!rc) {
-               ap->print_id = ata_print_id++;
+               ap->print_id = atomic_inc_return(&ata_print_id);
                __ata_port_probe(ap);
        }
 
@@ -3867,7 +3867,7 @@ int ata_sas_port_init(struct ata_port *ap)
        int rc = ap->ops->port_start(ap);
 
        if (!rc) {
-               ap->print_id = ata_print_id++;
+               ap->print_id = atomic_inc_return(&ata_print_id);
                rc = ata_port_probe(ap);
        }
 

diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 2e26fcaf635b211192238dcfea0d7eebdad5b25b..9d0fd0b7185224239030e51d42dbe83f27ebbafb 100644 (file)
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -53,7 +53,7 @@ enum {
        ATA_DNXFER_QUIET        = (1 << 31),
 };
 
-extern unsigned int ata_print_id;
+extern atomic_t ata_print_id;
 extern int atapi_passthru16;
 extern int libata_fua;
 extern int libata_noacpi;