kmem_zalloc with KM_SLEEP will never return NULL

These allocations can never fail.  Leaving the error handling
code here gives the impression they can so it has been removed.

Signed-off-by: luozhengzheng <luo.zhengzheng@zte.com.cn>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #5048

diff --git a/module/zfs/fm.c b/module/zfs/fm.c
index 09e7913b9d04c98475a5f35e3b0679609f4f0c8a..2a425a7401d2a5ae541abf42353c4f50e47c797d 100644 (file)
--- a/module/zfs/fm.c
+++ b/module/zfs/fm.c
@@ -426,8 +426,6 @@ zfs_zevent_alloc(void)
        zevent_t *ev;
 
        ev = kmem_zalloc(sizeof (zevent_t), KM_SLEEP);
-       if (ev == NULL)
-               return (NULL);
 
        list_create(&ev->ev_ze_list, sizeof (zfs_zevent_t),
                    offsetof(zfs_zevent_t, ze_node));

diff --git a/module/zpios/pios.c b/module/zpios/pios.c
index 8f4a8fd69b58074971f36303e6c8e0f33248ea2d..43af6bff0cecd44f16d8eaa27da201e678e2403d 100644 (file)
--- a/module/zpios/pios.c
+++ b/module/zpios/pios.c
@@ -287,11 +287,6 @@ zpios_setup_run(run_args_t **run_args, zpios_cmd_t *kcmd, struct file *file)
        size = sizeof (*ra) + kcmd->cmd_region_count * sizeof (zpios_region_t);
 
        ra = vmem_zalloc(size, KM_SLEEP);
-       if (ra == NULL) {
-               zpios_print(file, "Unable to vmem_zalloc() %d bytes "
-                           "for regions\n", size);
-               return (-ENOMEM);
-       }
 
        *run_args = ra;
        strncpy(ra->pool, kcmd->cmd_pool, ZPIOS_NAME_SIZE - 1);
@@ -734,16 +729,8 @@ zpios_threads_run(run_args_t *run_args)
        int i, rc = 0, tc = run_args->thread_count;
 
        tsks = kmem_zalloc(sizeof (struct task_struct *) * tc, KM_SLEEP);
-       if (tsks == NULL) {
-               rc = -ENOMEM;
-               goto cleanup2;
-       }
 
        run_args->threads = kmem_zalloc(sizeof (thread_data_t *)*tc, KM_SLEEP);
-       if (run_args->threads == NULL) {
-               rc = -ENOMEM;
-               goto cleanup;
-       }
 
        init_waitqueue_head(&run_args->waitq);
        run_args->threads_done = 0;
@@ -751,10 +738,6 @@ zpios_threads_run(run_args_t *run_args)
        /* Create all the needed threads which will sleep until awoken */
        for (i = 0; i < tc; i++) {
                thr = kmem_zalloc(sizeof (thread_data_t), KM_SLEEP);
-               if (thr == NULL) {
-                       rc = -ENOMEM;
-                       goto taskerr;
-               }
 
                thr->thread_no = i;
                thr->run_args = run_args;
@@ -846,8 +829,6 @@ out:
 
 cleanup:
        kmem_free(tsks, sizeof (struct task_struct *) * tc);
-cleanup2:
-       /* Returns first encountered thread error (if any) */
        return (rc);
 
 taskerr:
@@ -943,17 +924,11 @@ zpios_open(struct inode *inode, struct file *file)
        zpios_info_t *info;
 
        info = (zpios_info_t *)kmem_alloc(sizeof (*info), KM_SLEEP);
-       if (info == NULL)
-               return (-ENOMEM);
 
        spin_lock_init(&info->info_lock);
        info->info_size = ZPIOS_INFO_BUFFER_SIZE;
        info->info_buffer =
            (char *) vmem_alloc(ZPIOS_INFO_BUFFER_SIZE, KM_SLEEP);
-       if (info->info_buffer == NULL) {
-               kmem_free(info, sizeof (*info));
-               return (-ENOMEM);
-       }
 
        info->info_head = info->info_buffer;
        file->private_data = (void *)info;
@@ -1006,10 +981,6 @@ zpios_buffer_size(struct file *file, zpios_cfg_t *kcfg, unsigned long arg)
 
                size = kcfg->cfg_arg1;
                buf = (char *)vmem_alloc(size, KM_SLEEP);
-               if (buf == NULL) {
-                       rc = -ENOMEM;
-                       goto out;
-               }
 
                /* Zero fill and truncate contents when coping buffer */
                min = ((size < info->info_size) ? size : info->info_size);
@@ -1026,7 +997,7 @@ zpios_buffer_size(struct file *file, zpios_cfg_t *kcfg, unsigned long arg)
        if (copy_to_user((struct zpios_cfg_t __user *)arg,
            kcfg, sizeof (*kcfg)))
                rc = -EFAULT;
-out:
+
        spin_unlock(&info->info_lock);
 
        return (rc);
@@ -1080,11 +1051,6 @@ zpios_ioctl_cmd(struct file *file, unsigned long arg)
        int rc = -EINVAL;
 
        kcmd = kmem_alloc(sizeof (zpios_cmd_t), KM_SLEEP);
-       if (kcmd == NULL) {
-               zpios_print(file, "Unable to kmem_alloc() %ld byte for "
-                           "zpios_cmd_t\n", (long int)sizeof (zpios_cmd_t));
-               return (-ENOMEM);
-       }
 
        rc = copy_from_user(kcmd, (zpios_cfg_t *)arg, sizeof (zpios_cmd_t));
        if (rc) {
@@ -1103,13 +1069,6 @@ zpios_ioctl_cmd(struct file *file, unsigned long arg)
        /* Allocate memory for any opaque data the caller needed to pass on */
        if (kcmd->cmd_data_size > 0) {
                data = (void *)vmem_alloc(kcmd->cmd_data_size, KM_SLEEP);
-               if (data == NULL) {
-                       zpios_print(file, "Unable to vmem_alloc() %ld "
-                                   "bytes for data buffer\n",
-                                   (long)kcmd->cmd_data_size);
-                       rc = -ENOMEM;
-                       goto out_cmd;
-               }
 
                rc = copy_from_user(data, (void *)(arg + offsetof(zpios_cmd_t,
                    cmd_data_str)), kcmd->cmd_data_size);