Some issues resolved and bugs fixed, code for review and merge, thanks.

src/bio_helper.c

@@ -44,11 +44,10 @@ struct request_queue *dattobd_bio_get_queue(struct bio *bio)
  */
 void dattobd_bio_set_dev(struct bio *bio, struct block_device *bdev)
 {
-#ifdef HAVE_BIO_BI_BDEV
-        //#if LINUX_VERSION_CODE < KERNEL_VERSION(4,14,0)
-        bio->bi_bdev = bdev;
-#else
+#ifdef HAVE_BIO_SET_DEV
         bio_set_dev(bio, bdev);
+#else
+        bio->bi_bdev = bdev;
 #endif
 }
 

src/configure-tests/feature-tests/bio_set_dev.c

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Feature test: detect presence of bio_set_dev(bio, bdev)
+ */
+
+#include "includes.h"
+
+MODULE_LICENSE("GPL");
+
+static inline void dummy(void)
+{
+        struct bio *b = NULL;
+        struct block_device *d = NULL;
+        /* compile-time presence check */
+        bio_set_dev(b, d);
+}
+
+

src/cow_manager.c

@@ -505,8 +505,16 @@ int cow_sync_and_close(struct cow_manager *cm)
         if (ret)
                 goto error;
 
-        ret = cow_get_file_extents(cm->dev, cm->dfilp->filp);
-	if(ret) goto error;
+        /*
+         * If the fs support fiemap, we need to get the extents of the file,
+         * otherwise it is ignored.
+         */
+        if (cm->dfilp->filp->f_inode->i_op && cm->dfilp->filp->f_inode->i_op->fiemap) {
+                ret = cow_get_file_extents(cm->dev, cm->dfilp->filp);
+	        if(ret) goto error;
+        } else {
+                LOG_WARN("fiemap not supported, ignoring extents processing.");
+        }
 
         if (cm->dfilp){
                 __close_and_destroy_dattobd_mutable_file(cm->dfilp);
@@ -605,6 +613,7 @@ int cow_reload(const char *path, uint64_t elements, unsigned long sect_size,
         int ret;
         unsigned long i;
         struct cow_manager *cm;
+        struct snap_device *dev;
 
         LOG_DEBUG("allocating cow manager");
         cm = kzalloc(sizeof(struct cow_manager), GFP_KERNEL);
@@ -654,25 +663,31 @@ int cow_reload(const char *path, uint64_t elements, unsigned long sect_size,
                 cm->sects[i].has_data = 1;
         }
 
+        /* Get the dev of the cow manager and set the dev of the cow manager*/
+        dev = container_of(cm_out, struct snap_device, sd_cow);
+        LOG_DEBUG("cow_reload, setting dev of cow manager, cm: %p, dev: %p", cm, dev);
+        cm->dev = dev;
+
         *cm_out = cm;
         return 0;
 
 error:
         LOG_ERROR(ret, "error during cow manager initialization");
-        if (cm->dfilp){
-                __close_and_destroy_dattobd_mutable_file(cm->dfilp);
-                cm->dfilp = NULL;
-        }
 
-        if (cm->sects) {
-                if (cm->flags & (1 << COW_VMALLOC_UPPER))
-                        vfree(cm->sects);
-                else
-                        kfree(cm->sects);
-        }
+        if (cm) {
+                if (cm->dfilp){
+                        __close_and_destroy_dattobd_mutable_file(cm->dfilp);
+                        cm->dfilp = NULL;
+                }
 
-        if (cm)
+                if (cm->sects) {
+                        if (cm->flags & (1 << COW_VMALLOC_UPPER))
+                                vfree(cm->sects);
+                        else
+                                kfree(cm->sects);
+                }
                 kfree(cm);
+        }
 
         *cm_out = NULL;
         return ret;
@@ -775,21 +790,23 @@ int cow_init(struct snap_device *dev, const char *path, uint64_t elements, unsig
 
 error:
         LOG_ERROR(ret, "error during cow manager initialization");
-        if (cm->dfilp){
-                file_unlink(cm->dfilp);
-                __close_and_destroy_dattobd_mutable_file(cm->dfilp);
-                cm->dfilp = NULL;
-        }
 
-        if (cm->sects) {
-                if (cm->flags & (1 << COW_VMALLOC_UPPER))
-                        vfree(cm->sects);
-                else
-                        kfree(cm->sects);
-        }
+        if (cm) {
+                if (cm->dfilp){
+                        file_unlink(cm->dfilp);
+                        __close_and_destroy_dattobd_mutable_file(cm->dfilp);
+                        cm->dfilp = NULL;
+                }
+
+                if (cm->sects) {
+                        if (cm->flags & (1 << COW_VMALLOC_UPPER))
+                                vfree(cm->sects);
+                        else
+                                kfree(cm->sects);
+                }
 
-        if (cm)
                 kfree(cm);
+        }
 
         *cm_out = NULL;
         return ret;

src/ioctl_handlers.c

@@ -453,6 +453,7 @@ static int ioctl_expand_cow_file(uint64_t size, unsigned int minor)
         if(ret)
                 goto error;
 
+        put_snap_device_array(snap_devices);
         return 0;
 
 error:

src/proc_seq_file.c

@@ -245,8 +245,13 @@ static int dattobd_proc_show(struct seq_file *m, void *v)
 
 static int dattobd_proc_open(struct inode *inode, struct file *filp)
 {
-        mutex_lock(&ioctl_mutex);
-        return seq_open(filp, &dattobd_seq_proc_ops);
+	int ret;
+	mutex_lock(&ioctl_mutex);
+	ret = seq_open(filp, &dattobd_seq_proc_ops);
+	if (ret) {
+		mutex_unlock(&ioctl_mutex);
+	}
+	return ret;
 }
 
 static int dattobd_proc_release(struct inode *inode, struct file *file)