crypto: mxs-dcp - Remove global mutex

Remove mutex_lock from probe in order to avoid the following warning:

[    8.526613] Freeing unused kernel memory: 232K (c0683000 - c06bd000)
starting pid 56, tty '': '/etc/rc.d/rcS'
[    9.110314]
[    9.111864] =====================================
[    9.116603] [ BUG: init/1 still has locks held! ]
[    9.121488] 3.15.0-rc4-next-20140509-00001-g319564e #1154 Not tainted
[    9.128071] -------------------------------------
[    9.132825] 1 lock held by init/1:
[    9.136252]  #0:  (global_mutex){+.+.+.}, at: [<c0387d68>] mxs_dcp_probe+0x14
[    9.144196]
[    9.144196] stack backtrace:
[    9.148888] CPU: 0 PID: 1 Comm: init Not tainted 3.15.0-rc4-next-20140509-004
[    9.157610] [<c000da40>] (unwind_backtrace) from [<c000bda4>] (show_stack+0x)
[    9.165595] [<c000bda4>] (show_stack) from [<c00153d4>] (do_fork+0x2c8/0x3cc)
[    9.172921] [<c00153d4>] (do_fork) from [<c0015550>] (sys_vfork+0x20/0x2c)
[    9.179973] [<c0015550>] (sys_vfork) from [<c0009580>] (ret_fast_syscall+0x0)

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
index 7bbe0ab21eca70eb573cb645baf277ca141ba7b3..e48f0b87c383c04751f729ad35352f14354951fe 100644 (file)
--- a/drivers/crypto/mxs-dcp.c
+++ b/drivers/crypto/mxs-dcp.c
@@ -104,7 +104,6 @@ struct dcp_sha_req_ctx {
  * design of Linux Crypto API.
  */
 static struct dcp *global_sdcp;
-static DEFINE_MUTEX(global_mutex);
 
 /* DCP register layout. */
 #define MXS_DCP_CTRL                           0x00
@@ -907,60 +906,49 @@ static int mxs_dcp_probe(struct platform_device *pdev)
        struct resource *iores;
        int dcp_vmi_irq, dcp_irq;
 
-       mutex_lock(&global_mutex);
        if (global_sdcp) {
                dev_err(dev, "Only one DCP instance allowed!\n");
-               ret = -ENODEV;
-               goto err_mutex;
+               return -ENODEV;
        }
 
        iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        dcp_vmi_irq = platform_get_irq(pdev, 0);
-       if (dcp_vmi_irq < 0) {
-               ret = dcp_vmi_irq;
-               goto err_mutex;
-       }
+       if (dcp_vmi_irq < 0)
+               return dcp_vmi_irq;
 
        dcp_irq = platform_get_irq(pdev, 1);
-       if (dcp_irq < 0) {
-               ret = dcp_irq;
-               goto err_mutex;
-       }
+       if (dcp_irq < 0)
+               return dcp_irq;
 
        sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
-       if (!sdcp) {
-               ret = -ENOMEM;
-               goto err_mutex;
-       }
+       if (!sdcp)
+               return -ENOMEM;
 
        sdcp->dev = dev;
        sdcp->base = devm_ioremap_resource(dev, iores);
-       if (IS_ERR(sdcp->base)) {
-               ret = PTR_ERR(sdcp->base);
-               goto err_mutex;
-       }
+       if (IS_ERR(sdcp->base))
+               return PTR_ERR(sdcp->base);
+
 
        ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
                               "dcp-vmi-irq", sdcp);
        if (ret) {
                dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
-               goto err_mutex;
+               return ret;
        }
 
        ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
                               "dcp-irq", sdcp);
        if (ret) {
                dev_err(dev, "Failed to claim DCP IRQ!\n");
-               goto err_mutex;
+               return ret;
        }
 
        /* Allocate coherent helper block. */
        sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
                                   GFP_KERNEL);
-       if (!sdcp->coh) {
-               ret = -ENOMEM;
-               goto err_mutex;
-       }
+       if (!sdcp->coh)
+               return -ENOMEM;
 
        /* Re-align the structure so it fits the DCP constraints. */
        sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
@@ -968,7 +956,7 @@ static int mxs_dcp_probe(struct platform_device *pdev)
        /* Restart the DCP block. */
        ret = stmp_reset_block(sdcp->base);
        if (ret)
-               goto err_mutex;
+               return ret;
 
        /* Initialize control register. */
        writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
@@ -1006,8 +994,7 @@ static int mxs_dcp_probe(struct platform_device *pdev)
                                                      NULL, "mxs_dcp_chan/sha");
        if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
                dev_err(dev, "Error starting SHA thread!\n");
-               ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
-               goto err_mutex;
+               return PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
        }
 
        sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
@@ -1064,9 +1051,6 @@ err_destroy_aes_thread:
 
 err_destroy_sha_thread:
        kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
-
-err_mutex:
-       mutex_unlock(&global_mutex);
        return ret;
 }
 
@@ -1088,9 +1072,7 @@ static int mxs_dcp_remove(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, NULL);
 
-       mutex_lock(&global_mutex);
        global_sdcp = NULL;
-       mutex_unlock(&global_mutex);
 
        return 0;
 }