lkml.org 
[lkml]   [2016]   [Sep]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 21/46] mtd: nandsim: Implement preliminary destructor function
Date
From: Richard Weinberger <richard@nod.at>

This function will be used via ioctl() to remove nandsim instances.

Signed-off-by: Richard Weinberger <richard@nod.at>
---
drivers/mtd/nand/nandsim.c | 81 +++++++++++++++++++++++++++++++++++++++++++--
include/linux/mtd/nandsim.h | 2 +-
2 files changed, 79 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c
index 344f5c4..bac3fde 100644
--- a/drivers/mtd/nand/nandsim.c
+++ b/drivers/mtd/nand/nandsim.c
@@ -39,6 +39,7 @@
#include <linux/mtd/nandsim.h>
#include <linux/delay.h>
#include <linux/list.h>
+#include <linux/spinlock.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/fs.h>
@@ -328,7 +329,10 @@ struct ns_file_data {
*/
struct nandsim {
unsigned int index;
+ unsigned int refcnt;
+ spinlock_t refcnt_lock;
struct mtd_partition partitions[CONFIG_NANDSIM_MAX_PARTS];
+ bool destroying;
unsigned int nbparts;

uint busw; /* flash chip bus width (8 or 16) */
@@ -2509,6 +2513,41 @@ static int ns_ctrl_new_instance(struct ns_new_instance_req *req)
return ns->index;
}

+static int ns_ctrl_destroy_instance(struct ns_destroy_instance_req *req)
+{
+ struct mtd_info *nsmtd;
+ int id = req->id, ret = 0;
+ struct nand_chip *chip;
+ struct nandsim *ns;
+
+ if (id < 0 || id >= NS_MAX_DEVICES)
+ return -EINVAL;
+
+ mutex_lock(&ns_mtd_mutex);
+ nsmtd = ns_mtds[id];
+ if (nsmtd) {
+ chip = mtd_to_nand(nsmtd);
+ ns = nand_get_controller_data(chip);
+ spin_lock(&ns->refcnt_lock);
+ if (ns->refcnt > 0) {
+ ret = -EBUSY;
+ spin_unlock(&ns->refcnt_lock);
+ goto out;
+ }
+ ns->destroying = true;
+ spin_unlock(&ns->refcnt_lock);
+ ret = ns_destroy_instance(nsmtd);
+ if (ret)
+ goto out;
+ ns_mtds[id] = NULL;
+ }
+
+out:
+ mutex_unlock(&ns_mtd_mutex);
+
+ return ret;
+}
+
static long ns_ctrl_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -2543,6 +2582,32 @@ static struct miscdevice nandsim_ctrl_cdev = {
.fops = &nansim_ctrl_fops,
};

+static void ns_put_device(struct mtd_info *mtd)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct nandsim *ns = nand_get_controller_data(chip);
+
+ spin_lock(&ns->refcnt_lock);
+ ns->refcnt -= 1;
+ spin_unlock(&ns->refcnt_lock);
+}
+
+static int ns_get_device(struct mtd_info *mtd)
+{
+ int ret = 0;
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct nandsim *ns = nand_get_controller_data(chip);
+
+ spin_lock(&ns->refcnt_lock);
+ if (ns->destroying)
+ ret = -EBUSY;
+ else
+ ns->refcnt += 1;
+ spin_unlock(&ns->refcnt_lock);
+
+ return ret;
+}
+
struct mtd_info *ns_new_instance(struct nandsim_params *nsparam)
{
struct nand_chip *chip;
@@ -2587,6 +2652,7 @@ struct mtd_info *ns_new_instance(struct nandsim_params *nsparam)
INIT_LIST_HEAD(&nand->grave_pages);
INIT_LIST_HEAD(&nand->weak_pages);
INIT_LIST_HEAD(&nand->weak_blocks);
+ spin_lock_init(&nand->refcnt_lock);

/*
* Register simulator's callbacks.
@@ -2637,6 +2703,8 @@ struct mtd_info *ns_new_instance(struct nandsim_params *nsparam)
}

nsmtd->owner = THIS_MODULE;
+ nsmtd->_get_device = ns_get_device;
+ nsmtd->_put_device = ns_put_device;

if ((retval = parse_weakblocks(nand, nsparam->weakblocks)) != 0)
goto error;
@@ -2750,11 +2818,16 @@ error:
}
EXPORT_SYMBOL_GPL(ns_new_instance);

-void ns_destroy_instance(struct mtd_info *nsmtd)
+int ns_destroy_instance(struct mtd_info *nsmtd)
{
+ int i, ret;
struct nand_chip *chip = mtd_to_nand(nsmtd);
struct nandsim *ns = nand_get_controller_data(chip);
- int i;
+
+ ret = mtd_device_unregister(nsmtd);
+ if (ret)
+ return ret;
+ nand_cleanup(nsmtd);

nandsim_debugfs_remove(ns);
free_lists(ns);
@@ -2763,6 +2836,8 @@ void ns_destroy_instance(struct mtd_info *nsmtd)
for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)
kfree(ns->partitions[i].name);
kfree(mtd_to_nand(nsmtd)); /* Free other structures */
+
+ return 0;
}
EXPORT_SYMBOL_GPL(ns_destroy_instance);

@@ -2773,7 +2848,7 @@ static void ns_destroy_all(void)
mutex_lock(&ns_mtd_mutex);
for (i = 0; i < NS_MAX_DEVICES; i++)
if (ns_mtds[i])
- ns_destroy_instance(ns_mtds[i]);
+ WARN_ON(ns_destroy_instance(ns_mtds[i]) != 0);
mutex_unlock(&ns_mtd_mutex);
}

diff --git a/include/linux/mtd/nandsim.h b/include/linux/mtd/nandsim.h
index 6e3b4a2..a0ca0fb 100644
--- a/include/linux/mtd/nandsim.h
+++ b/include/linux/mtd/nandsim.h
@@ -75,7 +75,7 @@ struct ns_backend_ops {
};

struct mtd_info *ns_new_instance(struct nandsim_params *nsparam);
-void ns_destroy_instance(struct mtd_info *nsmtd);
+int ns_destroy_instance(struct mtd_info *nsmtd);
struct nandsim_geom *nandsim_get_geom(struct nandsim *ns);
struct nandsim_regs *nandsim_get_regs(struct nandsim *ns);
void nandsim_set_backend_data(struct nandsim *ns, void *data);
--
2.8.3
\
 
 \ /
  Last update: 2016-09-22 23:58    [W:0.346 / U:0.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site