[PATCH 1/2] mpt2sas: Refcount sas_device objects and fix unsafe list usage

From: Calvin Owens
Date: Sun Jul 12 2015 - 00:26:20 EST

These objects can be referenced concurrently throughout the driver, we
need a way to make sure threads can't delete them out from under each
other. This patch adds the refcount, and refactors the code to use it.

Additionally, we cannot iterate over the sas_device_list without
holding the lock, or we risk corrupting random memory if items are
added or deleted as we iterate. This patch refactors _scsih_probe_sas()
to use the sas_device_list in a safe way.

Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Bart Van Assche <bart.vanassche@xxxxxxxxxxx>
Signed-off-by: Calvin Owens <calvinowens@xxxxxx>
---
drivers/scsi/mpt2sas/mpt2sas_base.h | 22 +-
drivers/scsi/mpt2sas/mpt2sas_scsih.c | 434 ++++++++++++++++++++-----------
drivers/scsi/mpt2sas/mpt2sas_transport.c | 12 +-
3 files changed, 315 insertions(+), 153 deletions(-)

diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index caff8d1..78f41ac 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -238,6 +238,7 @@
* @flags: MPT_TARGET_FLAGS_XXX flags
* @deleted: target flaged for deletion
* @tm_busy: target is busy with TM request.
+ * @sdev: The sas_device associated with this target
*/
struct MPT2SAS_TARGET {
struct scsi_target *starget;
@@ -248,6 +249,7 @@ struct MPT2SAS_TARGET {
u32 flags;
u8 deleted;
u8 tm_busy;
+ struct _sas_device *sdev;
};


@@ -376,8 +378,24 @@ struct _sas_device {
u8 phy;
u8 responding;
u8 pfa_led_on;
+ struct kref refcount;
};

+static inline void sas_device_get(struct _sas_device *s)
+{
+ kref_get(&s->refcount);
+}
+
+static inline void sas_device_free(struct kref *r)
+{
+ kfree(container_of(r, struct _sas_device, refcount));
+}
+
+static inline void sas_device_put(struct _sas_device *s)
+{
+ kref_put(&s->refcount, sas_device_free);
+}
+
/**
* struct _raid_device - raid volume link list
* @list: sas device list
@@ -1095,7 +1113,9 @@ struct _sas_node *mpt2sas_scsih_expander_find_by_handle(struct MPT2SAS_ADAPTER *
u16 handle);
struct _sas_node *mpt2sas_scsih_expander_find_by_sas_address(struct MPT2SAS_ADAPTER
*ioc, u64 sas_address);
-struct _sas_device *mpt2sas_scsih_sas_device_find_by_sas_address(
+struct _sas_device *mpt2sas_get_sdev_by_addr(
+ struct MPT2SAS_ADAPTER *ioc, u64 sas_address);
+struct _sas_device *__mpt2sas_get_sdev_by_addr(
struct MPT2SAS_ADAPTER *ioc, u64 sas_address);

void mpt2sas_port_enable_complete(struct MPT2SAS_ADAPTER *ioc);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 3f26147..fad80ce 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -526,8 +526,43 @@ _scsih_determine_boot_device(struct MPT2SAS_ADAPTER *ioc,
}
}

+struct _sas_device *
+__mpt2sas_get_sdev_from_target(struct MPT2SAS_TARGET *tgt_priv)
+{
+ struct _sas_device *ret;
+
+ ret = tgt_priv->sdev;
+ if (ret)
+ sas_device_get(ret);
+
+ return ret;
+}
+
+struct _sas_device *
+__mpt2sas_get_sdev_by_addr(struct MPT2SAS_ADAPTER *ioc,
+ u64 sas_address)
+{
+ struct _sas_device *sas_device;
+
+ assert_spin_locked(&ioc->sas_device_lock);
+
+ list_for_each_entry(sas_device, &ioc->sas_device_list, list)
+ if (sas_device->sas_address == sas_address)
+ goto found_device;
+
+ list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
+ if (sas_device->sas_address == sas_address)
+ goto found_device;
+
+ return NULL;
+
+found_device:
+ sas_device_get(sas_device);
+ return sas_device;
+}
+
/**
- * mpt2sas_scsih_sas_device_find_by_sas_address - sas device search
+ * mpt2sas_get_sdev_by_addr - sas device search
* @ioc: per adapter object
* @sas_address: sas address
* Context: Calling function should acquire ioc->sas_device_lock
@@ -536,24 +571,44 @@ _scsih_determine_boot_device(struct MPT2SAS_ADAPTER *ioc,
* object.
*/
struct _sas_device *
-mpt2sas_scsih_sas_device_find_by_sas_address(struct MPT2SAS_ADAPTER *ioc,
+mpt2sas_get_sdev_by_addr(struct MPT2SAS_ADAPTER *ioc,
u64 sas_address)
{
struct _sas_device *sas_device;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
+ sas_address);
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+ return sas_device;
+}
+
+static struct _sas_device *
+__mpt2sas_get_sdev_by_handle(struct MPT2SAS_ADAPTER *ioc, u16 handle)
+{
+ struct _sas_device *sas_device;
+
+ assert_spin_locked(&ioc->sas_device_lock);

list_for_each_entry(sas_device, &ioc->sas_device_list, list)
- if (sas_device->sas_address == sas_address)
- return sas_device;
+ if (sas_device->handle == handle)
+ goto found_device;

list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
- if (sas_device->sas_address == sas_address)
- return sas_device;
+ if (sas_device->handle == handle)
+ goto found_device;

return NULL;
+
+found_device:
+ sas_device_get(sas_device);
+ return sas_device;
}

/**
- * _scsih_sas_device_find_by_handle - sas device search
+ * mpt2sas_get_sdev_by_handle - sas device search
* @ioc: per adapter object
* @handle: sas device handle (assigned by firmware)
* Context: Calling function should acquire ioc->sas_device_lock
@@ -562,19 +617,16 @@ mpt2sas_scsih_sas_device_find_by_sas_address(struct MPT2SAS_ADAPTER *ioc,
* object.
*/
static struct _sas_device *
-_scsih_sas_device_find_by_handle(struct MPT2SAS_ADAPTER *ioc, u16 handle)
+mpt2sas_get_sdev_by_handle(struct MPT2SAS_ADAPTER *ioc, u16 handle)
{
struct _sas_device *sas_device;
+ unsigned long flags;

- list_for_each_entry(sas_device, &ioc->sas_device_list, list)
- if (sas_device->handle == handle)
- return sas_device;
-
- list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
- if (sas_device->handle == handle)
- return sas_device;
+ spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

- return NULL;
+ return sas_device;
}

/**
@@ -583,7 +635,7 @@ _scsih_sas_device_find_by_handle(struct MPT2SAS_ADAPTER *ioc, u16 handle)
* @sas_device: the sas_device object
* Context: This function will acquire ioc->sas_device_lock.
*
- * Removing object and freeing associated memory from the ioc->sas_device_list.
+ * If sas_device is on the list, remove it and decrement its reference count.
*/
static void
_scsih_sas_device_remove(struct MPT2SAS_ADAPTER *ioc,
@@ -594,9 +646,15 @@ _scsih_sas_device_remove(struct MPT2SAS_ADAPTER *ioc,
if (!sas_device)
return;

+ /*
+ * The lock serializes access to the list, but we still need to verify
+ * that nobody removed the entry while we were waiting on the lock.
+ */
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- list_del(&sas_device->list);
- kfree(sas_device);
+ if (!list_empty(&sas_device->list)) {
+ list_del_init(&sas_device->list);
+ sas_device_put(sas_device);
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}

@@ -620,6 +678,7 @@ _scsih_sas_device_add(struct MPT2SAS_ADAPTER *ioc,
sas_device->handle, (unsigned long long)sas_device->sas_address));

spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ sas_device_get(sas_device);
list_add_tail(&sas_device->list, &ioc->sas_device_list);
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

@@ -659,6 +718,7 @@ _scsih_sas_device_init_add(struct MPT2SAS_ADAPTER *ioc,
sas_device->handle, (unsigned long long)sas_device->sas_address));

spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ sas_device_get(sas_device);
list_add_tail(&sas_device->list, &ioc->sas_device_init_list);
_scsih_determine_boot_device(ioc, sas_device, 0);
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
@@ -1208,12 +1268,14 @@ _scsih_change_queue_depth(struct scsi_device *sdev, int qdepth)
goto not_sata;
if ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME))
goto not_sata;
+
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- sas_device_priv_data->sas_target->sas_address);
- if (sas_device && sas_device->device_info &
- MPI2_SAS_DEVICE_INFO_SATA_DEVICE)
+ sas_device = __mpt2sas_get_sdev_from_target(sas_target_priv_data);
+ if (sas_device && sas_device->device_info
+ & MPI2_SAS_DEVICE_INFO_SATA_DEVICE) {
max_depth = MPT2SAS_SATA_QUEUE_DEPTH;
+ sas_device_put(sas_device);
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

not_sata:
@@ -1271,18 +1333,21 @@ _scsih_target_alloc(struct scsi_target *starget)
/* sas/sata devices */
spin_lock_irqsave(&ioc->sas_device_lock, flags);
rphy = dev_to_rphy(starget->dev.parent);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
rphy->identify.sas_address);

if (sas_device) {
sas_target_priv_data->handle = sas_device->handle;
sas_target_priv_data->sas_address = sas_device->sas_address;
+ sas_target_priv_data->sdev = sas_device;
sas_device->starget = starget;
sas_device->id = starget->id;
sas_device->channel = starget->channel;
if (test_bit(sas_device->handle, ioc->pd_handles))
sas_target_priv_data->flags |=
MPT_TARGET_FLAGS_RAID_COMPONENT;
+
+ sas_device_put(sas_device);
}
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

@@ -1324,13 +1389,14 @@ _scsih_target_destroy(struct scsi_target *starget)

spin_lock_irqsave(&ioc->sas_device_lock, flags);
rphy = dev_to_rphy(starget->dev.parent);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- rphy->identify.sas_address);
+ sas_device = __mpt2sas_get_sdev_from_target(sas_target_priv_data);
if (sas_device && (sas_device->starget == starget) &&
(sas_device->id == starget->id) &&
(sas_device->channel == starget->channel))
sas_device->starget = NULL;

+ if (sas_device)
+ sas_device_put(sas_device);
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

out:
@@ -1386,7 +1452,7 @@ _scsih_slave_alloc(struct scsi_device *sdev)

if (!(sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)) {
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
sas_target_priv_data->sas_address);
if (sas_device && (sas_device->starget == NULL)) {
sdev_printk(KERN_INFO, sdev,
@@ -1394,6 +1460,10 @@ _scsih_slave_alloc(struct scsi_device *sdev)
__func__, __LINE__);
sas_device->starget = starget;
}
+
+ if (sas_device)
+ sas_device_put(sas_device);
+
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}

@@ -1428,10 +1498,12 @@ _scsih_slave_destroy(struct scsi_device *sdev)

if (!(sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)) {
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- sas_target_priv_data->sas_address);
+ sas_device = __mpt2sas_get_sdev_from_target(sas_target_priv_data);
if (sas_device && !sas_target_priv_data->num_luns)
sas_device->starget = NULL;
+
+ if (sas_device)
+ sas_device_put(sas_device);
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}

@@ -2078,7 +2150,7 @@ _scsih_slave_configure(struct scsi_device *sdev)
}

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
sas_device_priv_data->sas_target->sas_address);
if (!sas_device) {
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
@@ -2116,13 +2188,14 @@ _scsih_slave_configure(struct scsi_device *sdev)
if (!ssp_target)
_scsih_display_sata_capabilities(ioc, handle, sdev);

-
_scsih_change_queue_depth(sdev, qdepth);

if (ssp_target) {
sas_read_port_mode_page(sdev);
_scsih_enable_tlr(ioc, sdev);
}
+
+ sas_device_put(sas_device);
return 0;
}

@@ -2509,8 +2582,7 @@ _scsih_tm_display_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd)
device_str, (unsigned long long)priv_target->sas_address);
} else {
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- priv_target->sas_address);
+ sas_device = __mpt2sas_get_sdev_from_target(priv_target);
if (sas_device) {
if (priv_target->flags &
MPT_TARGET_FLAGS_RAID_COMPONENT) {
@@ -2529,6 +2601,8 @@ _scsih_tm_display_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd)
"enclosure_logical_id(0x%016llx), slot(%d)\n",
(unsigned long long)sas_device->enclosure_logical_id,
sas_device->slot);
+
+ sas_device_put(sas_device);
}
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}
@@ -2604,12 +2678,12 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
{
struct MPT2SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
struct MPT2SAS_DEVICE *sas_device_priv_data;
- struct _sas_device *sas_device;
- unsigned long flags;
+ struct _sas_device *sas_device = NULL;
u16 handle;
int r;

struct scsi_target *starget = scmd->device->sdev_target;
+ struct MPT2SAS_TARGET *target_priv_data = starget->hostdata;

starget_printk(KERN_INFO, starget, "attempting device reset! "
"scmd(%p)\n", scmd);
@@ -2629,12 +2703,9 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
handle = 0;
if (sas_device_priv_data->sas_target->flags &
MPT_TARGET_FLAGS_RAID_COMPONENT) {
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc,
- sas_device_priv_data->sas_target->handle);
+ sas_device = __mpt2sas_get_sdev_from_target(target_priv_data);
if (sas_device)
handle = sas_device->volume_handle;
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
} else
handle = sas_device_priv_data->sas_target->handle;

@@ -2651,6 +2722,10 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
out:
sdev_printk(KERN_INFO, scmd->device, "device reset: %s scmd(%p)\n",
((r == SUCCESS) ? "SUCCESS" : "FAILED"), scmd);
+
+ if (sas_device)
+ sas_device_put(sas_device);
+
return r;
}

@@ -2665,11 +2740,11 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
{
struct MPT2SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
struct MPT2SAS_DEVICE *sas_device_priv_data;
- struct _sas_device *sas_device;
- unsigned long flags;
+ struct _sas_device *sas_device = NULL;
u16 handle;
int r;
struct scsi_target *starget = scmd->device->sdev_target;
+ struct MPT2SAS_TARGET *target_priv_data = starget->hostdata;

starget_printk(KERN_INFO, starget, "attempting target reset! "
"scmd(%p)\n", scmd);
@@ -2689,12 +2764,9 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
handle = 0;
if (sas_device_priv_data->sas_target->flags &
MPT_TARGET_FLAGS_RAID_COMPONENT) {
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc,
- sas_device_priv_data->sas_target->handle);
+ sas_device = __mpt2sas_get_sdev_from_target(target_priv_data);
if (sas_device)
handle = sas_device->volume_handle;
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
} else
handle = sas_device_priv_data->sas_target->handle;

@@ -2711,6 +2783,10 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
out:
starget_printk(KERN_INFO, starget, "target reset: %s scmd(%p)\n",
((r == SUCCESS) ? "SUCCESS" : "FAILED"), scmd);
+
+ if (sas_device)
+ sas_device_put(sas_device);
+
return r;
}

@@ -3002,15 +3078,15 @@ _scsih_block_io_to_children_attached_to_ex(struct MPT2SAS_ADAPTER *ioc,

list_for_each_entry(mpt2sas_port,
&sas_expander->sas_port_list, port_list) {
- if (mpt2sas_port->remote_identify.device_type ==
- SAS_END_DEVICE) {
+ if (mpt2sas_port->remote_identify.device_type == SAS_END_DEVICE) {
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device =
- mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- mpt2sas_port->remote_identify.sas_address);
- if (sas_device)
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
+ mpt2sas_port->remote_identify.sas_address);
+ if (sas_device) {
set_bit(sas_device->handle,
- ioc->blocking_handles);
+ ioc->blocking_handles);
+ sas_device_put(sas_device);
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}
}
@@ -3080,7 +3156,7 @@ _scsih_tm_tr_send(struct MPT2SAS_ADAPTER *ioc, u16 handle)
{
Mpi2SCSITaskManagementRequest_t *mpi_request;
u16 smid;
- struct _sas_device *sas_device;
+ struct _sas_device *sas_device = NULL;
struct MPT2SAS_TARGET *sas_target_priv_data = NULL;
u64 sas_address = 0;
unsigned long flags;
@@ -3110,7 +3186,7 @@ _scsih_tm_tr_send(struct MPT2SAS_ADAPTER *ioc, u16 handle)
return;

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
if (sas_device && sas_device->starget &&
sas_device->starget->hostdata) {
sas_target_priv_data = sas_device->starget->hostdata;
@@ -3131,14 +3207,14 @@ _scsih_tm_tr_send(struct MPT2SAS_ADAPTER *ioc, u16 handle)
if (!smid) {
delayed_tr = kzalloc(sizeof(*delayed_tr), GFP_ATOMIC);
if (!delayed_tr)
- return;
+ goto out;
INIT_LIST_HEAD(&delayed_tr->list);
delayed_tr->handle = handle;
list_add_tail(&delayed_tr->list, &ioc->delayed_tr_list);
dewtprintk(ioc, printk(MPT2SAS_INFO_FMT
"DELAYED:tr:handle(0x%04x), (open)\n",
ioc->name, handle));
- return;
+ goto out;
}

dewtprintk(ioc, printk(MPT2SAS_INFO_FMT "tr_send:handle(0x%04x), "
@@ -3150,6 +3226,9 @@ _scsih_tm_tr_send(struct MPT2SAS_ADAPTER *ioc, u16 handle)
mpi_request->DevHandle = cpu_to_le16(handle);
mpi_request->TaskType = MPI2_SCSITASKMGMT_TASKTYPE_TARGET_RESET;
mpt2sas_base_put_smid_hi_priority(ioc, smid);
+out:
+ if (sas_device)
+ sas_device_put(sas_device);
}


@@ -4068,7 +4147,6 @@ _scsih_scsi_ioc_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
char *desc_scsi_state = ioc->tmp_string;
u32 log_info = le32_to_cpu(mpi_reply->IOCLogInfo);
struct _sas_device *sas_device = NULL;
- unsigned long flags;
struct scsi_target *starget = scmd->device->sdev_target;
struct MPT2SAS_TARGET *priv_target = starget->hostdata;
char *device_str = NULL;
@@ -4200,9 +4278,7 @@ _scsih_scsi_ioc_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
printk(MPT2SAS_WARN_FMT "\t%s wwid(0x%016llx)\n", ioc->name,
device_str, (unsigned long long)priv_target->sas_address);
} else {
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- priv_target->sas_address);
+ sas_device = __mpt2sas_get_sdev_from_target(priv_target);
if (sas_device) {
printk(MPT2SAS_WARN_FMT "\tsas_address(0x%016llx), "
"phy(%d)\n", ioc->name, sas_device->sas_address,
@@ -4211,8 +4287,9 @@ _scsih_scsi_ioc_info(struct MPT2SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
"\tenclosure_logical_id(0x%016llx), slot(%d)\n",
ioc->name, sas_device->enclosure_logical_id,
sas_device->slot);
+
+ sas_device_put(sas_device);
}
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
}

printk(MPT2SAS_WARN_FMT "\thandle(0x%04x), ioc_status(%s)(0x%04x), "
@@ -4259,7 +4336,7 @@ _scsih_turn_on_pfa_led(struct MPT2SAS_ADAPTER *ioc, u16 handle)
Mpi2SepRequest_t mpi_request;
struct _sas_device *sas_device;

- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+ sas_device = mpt2sas_get_sdev_by_handle(ioc, handle);
if (!sas_device)
return;

@@ -4274,7 +4351,7 @@ _scsih_turn_on_pfa_led(struct MPT2SAS_ADAPTER *ioc, u16 handle)
&mpi_request)) != 0) {
printk(MPT2SAS_ERR_FMT "failure at %s:%d/%s()!\n", ioc->name,
__FILE__, __LINE__, __func__);
- return;
+ goto out;
}
sas_device->pfa_led_on = 1;

@@ -4284,8 +4361,10 @@ _scsih_turn_on_pfa_led(struct MPT2SAS_ADAPTER *ioc, u16 handle)
"enclosure_processor: ioc_status (0x%04x), loginfo(0x%08x)\n",
ioc->name, le16_to_cpu(mpi_reply.IOCStatus),
le32_to_cpu(mpi_reply.IOCLogInfo)));
- return;
+ goto out;
}
+out:
+ sas_device_put(sas_device);
}

/**
@@ -4370,19 +4449,17 @@ _scsih_smart_predicted_fault(struct MPT2SAS_ADAPTER *ioc, u16 handle)

/* only handle non-raid devices */
spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
if (!sas_device) {
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
+ goto out_unlock;
}
starget = sas_device->starget;
sas_target_priv_data = starget->hostdata;

if ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_RAID_COMPONENT) ||
- ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME))) {
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
- }
+ ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)))
+ goto out_unlock;
+
starget_printk(KERN_WARNING, starget, "predicted fault\n");
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

@@ -4396,7 +4473,7 @@ _scsih_smart_predicted_fault(struct MPT2SAS_ADAPTER *ioc, u16 handle)
if (!event_reply) {
printk(MPT2SAS_ERR_FMT "failure at %s:%d/%s()!\n",
ioc->name, __FILE__, __LINE__, __func__);
- return;
+ goto out;
}

event_reply->Function = MPI2_FUNCTION_EVENT_NOTIFICATION;
@@ -4413,6 +4490,14 @@ _scsih_smart_predicted_fault(struct MPT2SAS_ADAPTER *ioc, u16 handle)
event_data->SASAddress = cpu_to_le64(sas_target_priv_data->sas_address);
mpt2sas_ctl_add_to_event_log(ioc, event_reply);
kfree(event_reply);
+out:
+ if (sas_device)
+ sas_device_put(sas_device);
+ return;
+
+out_unlock:
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+ goto out;
}

/**
@@ -5148,14 +5233,13 @@ _scsih_check_device(struct MPT2SAS_ADAPTER *ioc, u16 handle)

spin_lock_irqsave(&ioc->sas_device_lock, flags);
sas_address = le64_to_cpu(sas_device_pg0.SASAddress);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
sas_address);

if (!sas_device) {
printk(MPT2SAS_ERR_FMT "device is not present "
"handle(0x%04x), no sas_device!!!\n", ioc->name, handle);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
+ goto out_unlock;
}

if (unlikely(sas_device->handle != handle)) {
@@ -5172,19 +5256,22 @@ _scsih_check_device(struct MPT2SAS_ADAPTER *ioc, u16 handle)
MPI2_SAS_DEVICE0_FLAGS_DEVICE_PRESENT)) {
printk(MPT2SAS_ERR_FMT "device is not present "
"handle(0x%04x), flags!!!\n", ioc->name, handle);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
+ goto out_unlock;
}

/* check if there were any issues with discovery */
if (_scsih_check_access_status(ioc, sas_address, handle,
- sas_device_pg0.AccessStatus)) {
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
- }
+ sas_device_pg0.AccessStatus))
+ goto out_unlock;
+
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
_scsih_ublock_io_device(ioc, sas_address);
+ return;

+out_unlock:
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+ if (sas_device)
+ sas_device_put(sas_device);
}

/**
@@ -5208,7 +5295,6 @@ _scsih_add_device(struct MPT2SAS_ADAPTER *ioc, u16 handle, u8 phy_num, u8 is_pd)
u32 ioc_status;
__le64 sas_address;
u32 device_info;
- unsigned long flags;

if ((mpt2sas_config_get_sas_device_pg0(ioc, &mpi_reply, &sas_device_pg0,
MPI2_SAS_DEVICE_PGAD_FORM_HANDLE, handle))) {
@@ -5250,14 +5336,13 @@ _scsih_add_device(struct MPT2SAS_ADAPTER *ioc, u16 handle, u8 phy_num, u8 is_pd)
return -1;
}

-
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = mpt2sas_get_sdev_by_addr(ioc,
sas_address);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);

- if (sas_device)
+ if (sas_device) {
+ sas_device_put(sas_device);
return 0;
+ }

sas_device = kzalloc(sizeof(struct _sas_device),
GFP_KERNEL);
@@ -5267,6 +5352,7 @@ _scsih_add_device(struct MPT2SAS_ADAPTER *ioc, u16 handle, u8 phy_num, u8 is_pd)
return -1;
}

+ kref_init(&sas_device->refcount);
sas_device->handle = handle;
if (_scsih_get_sas_address(ioc, le16_to_cpu
(sas_device_pg0.ParentDevHandle),
@@ -5344,7 +5430,6 @@ _scsih_remove_device(struct MPT2SAS_ADAPTER *ioc,
"handle(0x%04x), sas_addr(0x%016llx)\n", ioc->name, __func__,
sas_device->handle, (unsigned long long)
sas_device->sas_address));
- kfree(sas_device);
}
/**
* _scsih_device_remove_by_handle - removing device object by handle
@@ -5363,12 +5448,17 @@ _scsih_device_remove_by_handle(struct MPT2SAS_ADAPTER *ioc, u16 handle)
return;

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
- if (sas_device)
- list_del(&sas_device->list);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
+ if (sas_device) {
+ list_del_init(&sas_device->list);
+ sas_device_put(sas_device);
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- if (sas_device)
+
+ if (sas_device) {
_scsih_remove_device(ioc, sas_device);
+ sas_device_put(sas_device);
+ }
}

/**
@@ -5389,13 +5479,17 @@ mpt2sas_device_remove_by_sas_address(struct MPT2SAS_ADAPTER *ioc,
return;

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
- sas_address);
- if (sas_device)
- list_del(&sas_device->list);
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc, sas_address);
+ if (sas_device) {
+ list_del_init(&sas_device->list);
+ sas_device_put(sas_device);
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- if (sas_device)
+
+ if (sas_device) {
_scsih_remove_device(ioc, sas_device);
+ sas_device_put(sas_device);
+ }
}
#ifdef CONFIG_SCSI_MPT2SAS_LOGGING
/**
@@ -5716,26 +5810,28 @@ _scsih_sas_device_status_change_event(struct MPT2SAS_ADAPTER *ioc,

spin_lock_irqsave(&ioc->sas_device_lock, flags);
sas_address = le64_to_cpu(event_data->SASAddress);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
sas_address);

- if (!sas_device || !sas_device->starget) {
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
- }
+ if (!sas_device || !sas_device->starget)
+ goto out;

target_priv_data = sas_device->starget->hostdata;
- if (!target_priv_data) {
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- return;
- }
+ if (!target_priv_data)
+ goto out;

if (event_data->ReasonCode ==
MPI2_EVENT_SAS_DEV_STAT_RC_INTERNAL_DEVICE_RESET)
target_priv_data->tm_busy = 1;
else
target_priv_data->tm_busy = 0;
+
+out:
+ if (sas_device)
+ sas_device_put(sas_device);
+
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
}

#ifdef CONFIG_SCSI_MPT2SAS_LOGGING
@@ -6123,7 +6219,7 @@ _scsih_sas_pd_expose(struct MPT2SAS_ADAPTER *ioc,
u16 handle = le16_to_cpu(element->PhysDiskDevHandle);

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
if (sas_device) {
sas_device->volume_handle = 0;
sas_device->volume_wwid = 0;
@@ -6142,6 +6238,8 @@ _scsih_sas_pd_expose(struct MPT2SAS_ADAPTER *ioc,
/* exposing raid component */
if (starget)
starget_for_each_device(starget, NULL, _scsih_reprobe_lun);
+
+ sas_device_put(sas_device);
}

/**
@@ -6170,7 +6268,7 @@ _scsih_sas_pd_hide(struct MPT2SAS_ADAPTER *ioc,
&volume_wwid);

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+ sas_device = __mpt2sas_get_sdev_by_handle(ioc, handle);
if (sas_device) {
set_bit(handle, ioc->pd_handles);
if (sas_device->starget && sas_device->starget->hostdata) {
@@ -6189,6 +6287,8 @@ _scsih_sas_pd_hide(struct MPT2SAS_ADAPTER *ioc,
/* hiding raid component */
if (starget)
starget_for_each_device(starget, (void *)1, _scsih_reprobe_lun);
+
+ sas_device_put(sas_device);
}

/**
@@ -6221,7 +6321,6 @@ _scsih_sas_pd_add(struct MPT2SAS_ADAPTER *ioc,
Mpi2EventIrConfigElement_t *element)
{
struct _sas_device *sas_device;
- unsigned long flags;
u16 handle = le16_to_cpu(element->PhysDiskDevHandle);
Mpi2ConfigReply_t mpi_reply;
Mpi2SasDevicePage0_t sas_device_pg0;
@@ -6231,11 +6330,11 @@ _scsih_sas_pd_add(struct MPT2SAS_ADAPTER *ioc,

set_bit(handle, ioc->pd_handles);

- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- if (sas_device)
+ sas_device = mpt2sas_get_sdev_by_handle(ioc, handle);
+ if (sas_device) {
+ sas_device_put(sas_device);
return;
+ }

if ((mpt2sas_config_get_sas_device_pg0(ioc, &mpi_reply, &sas_device_pg0,
MPI2_SAS_DEVICE_PGAD_FORM_HANDLE, handle))) {
@@ -6509,7 +6608,6 @@ _scsih_sas_ir_physical_disk_event(struct MPT2SAS_ADAPTER *ioc,
u16 handle, parent_handle;
u32 state;
struct _sas_device *sas_device;
- unsigned long flags;
Mpi2ConfigReply_t mpi_reply;
Mpi2SasDevicePage0_t sas_device_pg0;
u32 ioc_status;
@@ -6542,12 +6640,11 @@ _scsih_sas_ir_physical_disk_event(struct MPT2SAS_ADAPTER *ioc,
if (!ioc->is_warpdrive)
set_bit(handle, ioc->pd_handles);

- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-
- if (sas_device)
+ sas_device = mpt2sas_get_sdev_by_handle(ioc, handle);
+ if (sas_device) {
+ sas_device_put(sas_device);
return;
+ }

if ((mpt2sas_config_get_sas_device_pg0(ioc, &mpi_reply,
&sas_device_pg0, MPI2_SAS_DEVICE_PGAD_FORM_HANDLE,
@@ -7015,6 +7112,7 @@ _scsih_remove_unresponding_sas_devices(struct MPT2SAS_ADAPTER *ioc)
struct _raid_device *raid_device, *raid_device_next;
struct list_head tmp_list;
unsigned long flags;
+ LIST_HEAD(head);

printk(MPT2SAS_INFO_FMT "removing unresponding devices: start\n",
ioc->name);
@@ -7022,14 +7120,29 @@ _scsih_remove_unresponding_sas_devices(struct MPT2SAS_ADAPTER *ioc)
/* removing unresponding end devices */
printk(MPT2SAS_INFO_FMT "removing unresponding devices: end-devices\n",
ioc->name);
+
+ /*
+ * Iterate, pulling off devices marked as non-responding. We become the
+ * owner for the reference the list had on any object we prune.
+ */
+ spin_lock_irqsave(&ioc->sas_device_lock, flags);
list_for_each_entry_safe(sas_device, sas_device_next,
- &ioc->sas_device_list, list) {
+ &ioc->sas_device_list, list) {
if (!sas_device->responding)
- mpt2sas_device_remove_by_sas_address(ioc,
- sas_device->sas_address);
+ list_move_tail(&sas_device->list, &head);
else
sas_device->responding = 0;
}
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+ /*
+ * Now, uninitialize and remove the unresponding devices we pruned.
+ */
+ list_for_each_entry_safe(sas_device, sas_device_next, &head, list) {
+ _scsih_remove_device(ioc, sas_device);
+ list_del_init(&sas_device->list);
+ sas_device_put(sas_device);
+ }

/* removing unresponding volumes */
if (ioc->ir_firmware) {
@@ -7179,11 +7292,11 @@ _scsih_scan_for_devices_after_reset(struct MPT2SAS_ADAPTER *ioc)
}
phys_disk_num = pd_pg0.PhysDiskNum;
handle = le16_to_cpu(pd_pg0.DevHandle);
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- if (sas_device)
+ sas_device = mpt2sas_get_sdev_by_handle(ioc, handle);
+ if (sas_device) {
+ sas_device_put(sas_device);
continue;
+ }
if (mpt2sas_config_get_sas_device_pg0(ioc, &mpi_reply,
&sas_device_pg0, MPI2_SAS_DEVICE_PGAD_FORM_HANDLE,
handle) != 0)
@@ -7302,12 +7415,12 @@ _scsih_scan_for_devices_after_reset(struct MPT2SAS_ADAPTER *ioc)
if (!(_scsih_is_end_device(
le32_to_cpu(sas_device_pg0.DeviceInfo))))
continue;
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = mpt2sas_get_sdev_by_addr(ioc,
le64_to_cpu(sas_device_pg0.SASAddress));
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
- if (sas_device)
+ if (sas_device) {
+ sas_device_put(sas_device);
continue;
+ }
parent_handle = le16_to_cpu(sas_device_pg0.ParentDevHandle);
if (!_scsih_get_sas_address(ioc, parent_handle, &sas_address)) {
printk(MPT2SAS_INFO_FMT "\tBEFORE adding end device: "
@@ -7966,6 +8079,37 @@ _scsih_probe_raid(struct MPT2SAS_ADAPTER *ioc)
}
}

+static struct _sas_device *dequeue_next_sas_device(struct MPT2SAS_ADAPTER *ioc)
+{
+ struct _sas_device *sas_device = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ if (!list_empty(&ioc->sas_device_init_list)) {
+ sas_device = list_first_entry(&ioc->sas_device_init_list,
+ struct _sas_device, list);
+ list_del_init(&sas_device->list);
+ }
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+ /*
+ * If an item was dequeued, the caller now owns the reference that was
+ * previously owned by the list
+ */
+ return sas_device;
+}
+
+static void sas_device_make_active(struct MPT2SAS_ADAPTER *ioc,
+ struct _sas_device *sas_device)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ioc->sas_device_lock, flags);
+ sas_device_get(sas_device);
+ list_add_tail(&sas_device->list, &ioc->sas_device_list);
+ spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+}
+
/**
* _scsih_probe_sas - reporting sas devices to sas transport
* @ioc: per adapter object
@@ -7975,34 +8119,28 @@ _scsih_probe_raid(struct MPT2SAS_ADAPTER *ioc)
static void
_scsih_probe_sas(struct MPT2SAS_ADAPTER *ioc)
{
- struct _sas_device *sas_device, *next;
- unsigned long flags;
-
- /* SAS Device List */
- list_for_each_entry_safe(sas_device, next, &ioc->sas_device_init_list,
- list) {
+ struct _sas_device *sas_device;

- if (ioc->hide_drives)
- continue;
+ if (ioc->hide_drives)
+ return;

+ while ((sas_device = dequeue_next_sas_device(ioc))) {
if (!mpt2sas_transport_port_add(ioc, sas_device->handle,
- sas_device->sas_address_parent)) {
- list_del(&sas_device->list);
- kfree(sas_device);
+ sas_device->sas_address_parent)) {
+ sas_device_put(sas_device);
continue;
} else if (!sas_device->starget) {
if (!ioc->is_driver_loading) {
mpt2sas_transport_port_remove(ioc,
- sas_device->sas_address,
- sas_device->sas_address_parent);
- list_del(&sas_device->list);
- kfree(sas_device);
+ sas_device->sas_address,
+ sas_device->sas_address_parent);
+ sas_device_put(sas_device);
continue;
}
}
- spin_lock_irqsave(&ioc->sas_device_lock, flags);
- list_move_tail(&sas_device->list, &ioc->sas_device_list);
- spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+ sas_device_make_active(ioc, sas_device);
+ sas_device_put(sas_device);
}
}

diff --git a/drivers/scsi/mpt2sas/mpt2sas_transport.c b/drivers/scsi/mpt2sas/mpt2sas_transport.c
index ff2500a..af86800 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_transport.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_transport.c
@@ -1323,15 +1323,17 @@ _transport_get_enclosure_identifier(struct sas_rphy *rphy, u64 *identifier)
int rc;

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
rphy->identify.sas_address);
if (sas_device) {
*identifier = sas_device->enclosure_logical_id;
rc = 0;
+ sas_device_put(sas_device);
} else {
*identifier = 0;
rc = -ENXIO;
}
+
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
return rc;
}
@@ -1351,12 +1353,14 @@ _transport_get_bay_identifier(struct sas_rphy *rphy)
int rc;

spin_lock_irqsave(&ioc->sas_device_lock, flags);
- sas_device = mpt2sas_scsih_sas_device_find_by_sas_address(ioc,
+ sas_device = __mpt2sas_get_sdev_by_addr(ioc,
rphy->identify.sas_address);
- if (sas_device)
+ if (sas_device) {
rc = sas_device->slot;
- else
+ sas_device_put(sas_device);
+ } else {
rc = -ENXIO;
+ }
spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
return rc;
}
--
1.8.1

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