projects / people / pmueller / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| 82094b55 AF |
1 | From: Hannes Reinecke <hare@suse.de> |
| 2 | Date: Tue, 18 Aug 2009 10:26:50 +0200 | |
| 3 | Subject: libiscsi: check suspend bit before each call to xmit_task | |
| 4 | References: bnc#472432 | |
| 5 | X-Git: 70b31c152dc49ef70bd2b34ad53ccbd9bb4116d4 | |
| 6 | ||
| 7 | If we had multiple tasks on the cmd or requeue lists, and iscsi_tcp | |
| 8 | returns a error, the write_space function can still run and queue | |
| 9 | iscsi_data_xmit. If it was a legetimate problem and iscsi_conn_failure | |
| 10 | was run but we raced and iscsi_data_xmit was run first it could miss | |
| 11 | the suspend bit checks, and start trying to send data again and hit | |
| 12 | another timeout. A similar problem is present when using cxgb3i. | |
| 13 | ||
| 14 | This has libiscsi check the suspend bit before calling the xmit | |
| 15 | task callout, so we at least do not try sending multiple tasks | |
| 16 | (one could be sent). | |
| 17 | ||
| 18 | It also adds a check in iscsi_tcp before calling | |
| 19 | the send function. The extra call in iscsi_tcp is needed because | |
| 20 | we can call sendpage/sendmsg multiple times for the same pdu | |
| 21 | and between each call iscsi_conn_failure could be called. | |
| 22 | ||
| 23 | Backported to SLES11. | |
| 24 | ||
| 25 | Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> | |
| 26 | Signed-off-by: Hannes Reinecke <hare@suse.de> | |
| 27 | --- | |
| 28 | drivers/scsi/libiscsi.c | 19 ++++++++++--------- | |
| 29 | 1 files changed, 10 insertions(+), 9 deletions(-) | |
| 30 | ||
| 31 | diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c | |
| 32 | index 0611558..95720cc 100644 | |
| 33 | --- a/drivers/scsi/libiscsi.c | |
| 34 | +++ b/drivers/scsi/libiscsi.c | |
| 35 | @@ -1150,6 +1150,9 @@ static int iscsi_xmit_task(struct iscsi_conn *conn) | |
| 36 | struct iscsi_task *task = conn->task; | |
| 37 | int rc; | |
| 38 | ||
| 39 | + if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) | |
| 40 | + return -ENODATA; | |
| 41 | + | |
| 42 | __iscsi_get_task(task); | |
| 43 | spin_unlock_bh(&conn->session->lock); | |
| 44 | rc = conn->session->tt->xmit_task(task); | |
| 45 | @@ -1192,7 +1195,7 @@ static int iscsi_data_xmit(struct iscsi_conn *conn) | |
| 46 | int rc = 0; | |
| 47 | ||
| 48 | spin_lock_bh(&conn->session->lock); | |
| 49 | - if (unlikely(conn->suspend_tx)) { | |
| 50 | + if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) { | |
| 51 | debug_scsi("conn %d Tx suspended!\n", conn->id); | |
| 52 | spin_unlock_bh(&conn->session->lock); | |
| 53 | return -ENODATA; | |
| 54 | @@ -1200,8 +1203,8 @@ static int iscsi_data_xmit(struct iscsi_conn *conn) | |
| 55 | ||
| 56 | if (conn->task) { | |
| 57 | rc = iscsi_xmit_task(conn); | |
| 58 | - if (rc) | |
| 59 | - goto again; | |
| 60 | + if (rc) | |
| 61 | + goto done; | |
| 62 | } | |
| 63 | ||
| 64 | /* | |
| 65 | @@ -1220,7 +1223,7 @@ check_mgmt: | |
| 66 | } | |
| 67 | rc = iscsi_xmit_task(conn); | |
| 68 | if (rc) | |
| 69 | - goto again; | |
| 70 | + goto done; | |
| 71 | } | |
| 72 | ||
| 73 | /* process pending command queue */ | |
| 74 | @@ -1240,7 +1243,7 @@ check_mgmt: | |
| 75 | } | |
| 76 | rc = iscsi_xmit_task(conn); | |
| 77 | if (rc) | |
| 78 | - goto again; | |
| 79 | + goto done; | |
| 80 | /* | |
| 81 | * we could continuously get new task requests so | |
| 82 | * we need to check the mgmt queue for nops that need to | |
| 83 | @@ -1266,16 +1269,14 @@ check_mgmt: | |
| 84 | list_move_tail(conn->requeue.next, &conn->run_list); | |
| 85 | rc = iscsi_xmit_task(conn); | |
| 86 | if (rc) | |
| 87 | - goto again; | |
| 88 | + goto done; | |
| 89 | if (!list_empty(&conn->mgmtqueue)) | |
| 90 | goto check_mgmt; | |
| 91 | } | |
| 92 | spin_unlock_bh(&conn->session->lock); | |
| 93 | return -ENODATA; | |
| 94 | ||
| 95 | -again: | |
| 96 | - if (unlikely(conn->suspend_tx)) | |
| 97 | - rc = -ENODATA; | |
| 98 | +done: | |
| 99 | spin_unlock_bh(&conn->session->lock); | |
| 100 | return rc; | |
| 101 | } | |
| 102 | -- | |
| 103 | 1.6.0.2 | |
| 104 |