scst: Use kernel_{read,write}() instead of scst_{read,write}()

This patch does not change any functionality.


git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@8065 d57e44dd-8a1f-0410-8b47-8ef2f437770f

scst/include/backport.h

@@ -452,6 +452,24 @@ kernel_read_backport(struct file *file, void *buf, size_t count, loff_t *pos)
 
 #define kernel_read(file, buf, count, pos)			\
 	kernel_read_backport((file), (buf), (count), (pos))
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 9, 0)
+/*
+ * See also commit 7bb307e894d5 ("export kernel_write(), convert open-coded
+ * instances") # v3.9.
+ */
+static inline ssize_t
+kernel_write_backport(struct file *file, const void *buf, size_t count,
+		      loff_t *pos)
+{
+	return kernel_write(file, buf, count, *pos);
+}
+
+#define kernel_write kernel_write_backport
+#else
+ssize_t kernel_write(struct file *file, const void *buf, size_t count,
+		     loff_t *pos);
+#endif
 #endif
 
 /* <linux/iocontext.h> */

scst/include/scst.h

@@ -5599,9 +5599,6 @@ struct scst_data_descriptor {
 	uint64_t sdd_blocks;
 };
 
-ssize_t scst_read(struct file *file, void *buf, size_t count, loff_t *pos);
-ssize_t scst_write(struct file *file, const void *buf, size_t count,
-		   loff_t *pos);
 ssize_t scst_readv(struct file *file, const struct iovec *vec,
 		   unsigned long vlen, loff_t *pos);
 ssize_t scst_writev(struct file *file, const struct iovec *vec,

scst/src/dev_handlers/scst_vdisk.c

@@ -2995,21 +2995,6 @@ out:
 	return ret;
 }
 
-/* Note: Updates *@loff if reading succeeded. */
-static ssize_t fileio_read_sync(struct file *fd, void *buf, size_t len,
-				loff_t *loff)
-{
-	mm_segment_t old_fs;
-	ssize_t ret;
-
-	old_fs = get_fs();
-	set_fs(KERNEL_DS);
-	ret = scst_read(fd, buf, len, loff);
-	set_fs(old_fs);
-
-	return ret;
-}
-
 /* Note: Updates *@loff if reading succeeded except for NULLIO devices. */
 static ssize_t vdev_read_sync(struct scst_vdisk_dev *virt_dev, void *buf,
 			      size_t len, loff_t *loff)
@@ -3027,7 +3012,7 @@ static ssize_t vdev_read_sync(struct scst_vdisk_dev *virt_dev, void *buf,
 		}
 		return read;
 	} else {
-		return fileio_read_sync(virt_dev->fd, buf, len, loff);
+		return kernel_read(virt_dev->fd, buf, len, loff);
 	}
 }
 

scst/src/scst_lib.c

@@ -5933,44 +5933,31 @@ static int scst_cmp_fs_ds(void)
 	return memcmp(&fs, &ds, sizeof(fs));
 }
 
-ssize_t scst_read(struct file *file, void *buf, size_t count, loff_t *pos)
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 9, 0) && !defined(RHEL_MAJOR)
+ssize_t kernel_write(struct file *file, const void *buf, size_t count,
+		     loff_t *pos)
 {
+	mm_segment_t old_fs = get_fs();
+	ssize_t result;
+	set_fs(KERNEL_DS);
+	{
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 14, 0)
 	struct iovec iov = {
 		.iov_base = (void __force __user *)buf,
 		.iov_len = count
 	};
 
-	WARN_ON_ONCE(scst_cmp_fs_ds() != 0);
-
-	return scst_readv(file, &iov, 1, pos);
+	result = scst_writev(file, &iov, 1, pos);
 #else
-	WARN_ON_ONCE(scst_cmp_fs_ds() != 0);
-
-	return vfs_read(file, (void __force __user *)buf, count, pos);
+	result = vfs_write(file, (void __force __user *)buf, count, pos);
 #endif
+	}
+	set_fs(old_fs);
+
+	return result;
 }
-EXPORT_SYMBOL(scst_read);
-
-ssize_t scst_write(struct file *file, const void *buf, size_t count,
-		   loff_t *pos)
-{
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 14, 0)
-	struct iovec iov = {
-		.iov_base = (void __force __user *)buf,
-		.iov_len = count
-	};
-
-	WARN_ON_ONCE(scst_cmp_fs_ds() != 0);
-
-	return scst_writev(file, &iov, 1, pos);
-#else
-	WARN_ON_ONCE(scst_cmp_fs_ds() != 0);
-
-	return vfs_write(file, (void __force __user *)buf, count, pos);
+EXPORT_SYMBOL(kernel_write);
 #endif
-}
-EXPORT_SYMBOL(scst_write);
 
 ssize_t scst_readv(struct file *file, const struct iovec *vec,
 		   unsigned long vlen, loff_t *pos)
@@ -15044,7 +15031,6 @@ int scst_copy_file(const char *src, const char *dest)
 	loff_t file_size, pos;
 	uint8_t *buf = NULL;
 	struct file *file_src = NULL, *file_dest = NULL;
-	mm_segment_t old_fs = get_fs();
 
 	TRACE_ENTRY();
 
@@ -15057,8 +15043,6 @@ int scst_copy_file(const char *src, const char *dest)
 
 	TRACE_DBG("Copying '%s' into '%s'", src, dest);
 
-	set_fs(KERNEL_DS);
-
 	file_src = filp_open(src, O_RDONLY, 0);
 	if (IS_ERR(file_src)) {
 		res = PTR_ERR(file_src);
@@ -15083,7 +15067,6 @@ int scst_copy_file(const char *src, const char *dest)
 	} else {
 		PRINT_ERROR("Invalid file mode 0x%x", inode->i_mode);
 		res = -EINVAL;
-		set_fs(old_fs);
 		goto out_skip;
 	}
 
@@ -15097,14 +15080,14 @@ int scst_copy_file(const char *src, const char *dest)
 	}
 
 	pos = 0;
-	res = scst_read(file_src, buf, file_size, &pos);
+	res = kernel_read(file_src, buf, file_size, &pos);
 	if (res != file_size) {
 		PRINT_ERROR("Unable to read file '%s' - error %d", src, res);
 		goto out_skip;
 	}
 
 	pos = 0;
-	res = scst_write(file_dest, buf, file_size, &pos);
+	res = kernel_write(file_dest, buf, file_size, &pos);
 	if (res != file_size) {
 		PRINT_ERROR("Unable to write to '%s' - error %d", dest, res);
 		goto out_skip;
@@ -15126,8 +15109,6 @@ out_free:
 	if (buf != NULL)
 		vfree(buf);
 
-	set_fs(old_fs);
-
 out:
 	TRACE_EXIT_RES(res);
 	return res;
@@ -15174,7 +15155,6 @@ int scst_write_file_transactional(const char *name, const char *name1,
 {
 	int res;
 	struct file *file;
-	mm_segment_t old_fs = get_fs();
 	loff_t pos = 0;
 	char n = '\n';
 
@@ -15184,8 +15164,6 @@ int scst_write_file_transactional(const char *name, const char *name1,
 	if ((res != 0) && (res != -ENOENT))
 		goto out;
 
-	set_fs(KERNEL_DS);
-
 	file = filp_open(name, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 	if (IS_ERR(file)) {
 		res = PTR_ERR(file);
@@ -15198,7 +15176,7 @@ int scst_write_file_transactional(const char *name, const char *name1,
 
 	pos = signature_len+1;
 
-	res = scst_write(file, buf, size, &pos);
+	res = kernel_write(file, buf, size, &pos);
 	if (res != size)
 		goto write_error;
 
@@ -15209,11 +15187,11 @@ int scst_write_file_transactional(const char *name, const char *name1,
 	}
 
 	pos = 0;
-	res = scst_write(file, signature, signature_len, &pos);
+	res = kernel_write(file, signature, signature_len, &pos);
 	if (res != signature_len)
 		goto write_error;
 
-	res = scst_write(file, &n, sizeof(n), &pos);
+	res = kernel_write(file, &n, sizeof(n), &pos);
 	if (res != sizeof(n))
 		goto write_error;
 
@@ -15228,8 +15206,6 @@ int scst_write_file_transactional(const char *name, const char *name1,
 	filp_close(file, NULL);
 
 out_set_fs:
-	set_fs(old_fs);
-
 	if (res == 0)
 		scst_remove_file(name1);
 	else
@@ -15257,13 +15233,9 @@ static int __scst_read_file_transactional(const char *file_name,
 	struct file *file = NULL;
 	struct inode *inode;
 	loff_t file_size, pos;
-	mm_segment_t old_fs;
 
 	TRACE_ENTRY();
 
-	old_fs = get_fs();
-	set_fs(KERNEL_DS);
-
 	TRACE_DBG("Loading file '%s'", file_name);
 
 	file = filp_open(file_name, O_RDONLY, 0);
@@ -15295,7 +15267,7 @@ static int __scst_read_file_transactional(const char *file_name,
 	}
 
 	pos = 0;
-	res = scst_read(file, buf, file_size, &pos);
+	res = kernel_read(file, buf, file_size, &pos);
 	if (res != file_size) {
 		PRINT_ERROR("Unable to read file '%s' - error %d", file_name, res);
 		if (res > 0)
@@ -15313,8 +15285,6 @@ out_close:
 	filp_close(file, NULL);
 
 out:
-	set_fs(old_fs);
-
 	TRACE_EXIT_RES(res);
 	return res;
 }

scst/src/scst_pres.c

@@ -664,7 +664,6 @@ static int scst_pr_do_load_device_file(struct scst_device *dev,
 	char *buf = NULL;
 	loff_t file_size, pos, data_size;
 	uint64_t sign, version;
-	mm_segment_t old_fs;
 	uint8_t pr_is_set, aptpl;
 	__be64 key;
 	uint16_t rel_tgt_id;
@@ -675,9 +674,6 @@ static int scst_pr_do_load_device_file(struct scst_device *dev,
 
 	scst_pr_remove_registrants(dev);
 
-	old_fs = get_fs();
-	set_fs(KERNEL_DS);
-
 	TRACE_PR("Loading persistent file '%s'", file_name);
 
 	file = filp_open(file_name, O_RDONLY, 0);
@@ -715,7 +711,7 @@ static int scst_pr_do_load_device_file(struct scst_device *dev,
 	}
 
 	pos = 0;
-	rc = scst_read(file, buf, file_size, &pos);
+	rc = kernel_read(file, buf, file_size, &pos);
 	if (rc != file_size) {
 		PRINT_ERROR("Unable to read file '%s' - error %d", file_name,
 			rc);
@@ -822,8 +818,6 @@ out:
 	if (buf != NULL)
 		vfree(buf);
 
-	set_fs(old_fs);
-
 	TRACE_EXIT_RES(res);
 	return res;
 }
@@ -885,7 +879,6 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 {
 	int res = 0;
 	struct file *file;
-	mm_segment_t old_fs = get_fs();
 	loff_t pos = 0;
 	uint64_t sign;
 	uint64_t version;
@@ -903,14 +896,12 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 
 	scst_copy_file(dev->pr_file_name, dev->pr_file_name1);
 
-	set_fs(KERNEL_DS);
-
 	file = filp_open(dev->pr_file_name, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 	if (IS_ERR(file)) {
 		res = PTR_ERR(file);
 		PRINT_ERROR("Unable to (re)create PR file '%s' - error %d",
 			dev->pr_file_name, res);
-		goto out_set_fs;
+		goto out;
 	}
 
 	TRACE_PR("Updating pr file '%s'", dev->pr_file_name);
@@ -920,7 +911,7 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 	 */
 	sign = 0;
 	pos = 0;
-	res = scst_write(file, &sign, sizeof(sign), &pos);
+	res = kernel_write(file, &sign, sizeof(sign), &pos);
 	if (res != sizeof(sign))
 		goto write_error;
 
@@ -928,7 +919,7 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 	 * version
 	 */
 	version = SCST_PR_FILE_VERSION;
-	res = scst_write(file, &version, sizeof(version), &pos);
+	res = kernel_write(file, &version, sizeof(version), &pos);
 	if (res != sizeof(version))
 		goto write_error;
 
@@ -936,7 +927,7 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 	 * APTPL
 	 */
 	aptpl = dev->pr_aptpl;
-	res = scst_write(file, &aptpl, sizeof(aptpl), &pos);
+	res = kernel_write(file, &aptpl, sizeof(aptpl), &pos);
 	if (res != sizeof(aptpl))
 		goto write_error;
 
@@ -944,15 +935,15 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 	 * reservation
 	 */
 	pr_is_set = dev->pr_is_set;
-	res = scst_write(file, &pr_is_set, sizeof(pr_is_set), &pos);
+	res = kernel_write(file, &pr_is_set, sizeof(pr_is_set), &pos);
 	if (res != sizeof(pr_is_set))
 		goto write_error;
 
-	res = scst_write(file, &dev->pr_type, sizeof(dev->pr_type), &pos);
+	res = kernel_write(file, &dev->pr_type, sizeof(dev->pr_type), &pos);
 	if (res != sizeof(dev->pr_type))
 		goto write_error;
 
-	res = scst_write(file, &dev->pr_scope, sizeof(dev->pr_scope), &pos);
+	res = kernel_write(file, &dev->pr_scope, sizeof(dev->pr_scope), &pos);
 	if (res != sizeof(dev->pr_scope))
 		goto write_error;
 
@@ -966,24 +957,21 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 
 		is_holder = (dev->pr_holder == reg);
 
-		res = scst_write(file, &is_holder,
-				sizeof(is_holder), &pos);
+		res = kernel_write(file, &is_holder, sizeof(is_holder), &pos);
 		if (res != sizeof(is_holder))
 			goto write_error;
 
 		size = scst_tid_size(reg->transport_id);
-		res = scst_write(file, reg->transport_id,
-				size, &pos);
+		res = kernel_write(file, reg->transport_id, size, &pos);
 		if (res != size)
 			goto write_error;
 
-		res = scst_write(file, &reg->key,
-				sizeof(reg->key), &pos);
+		res = kernel_write(file, &reg->key, sizeof(reg->key), &pos);
 		if (res != sizeof(reg->key))
 			goto write_error;
 
-		res = scst_write(file, &reg->rel_tgt_id,
-				sizeof(reg->rel_tgt_id), &pos);
+		res = kernel_write(file, &reg->rel_tgt_id,
+				   sizeof(reg->rel_tgt_id), &pos);
 		if (res != sizeof(reg->rel_tgt_id))
 			goto write_error;
 	}
@@ -996,7 +984,7 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 
 	sign = SCST_PR_FILE_SIGN;
 	pos = 0;
-	res = scst_write(file, &sign, sizeof(sign), &pos);
+	res = kernel_write(file, &sign, sizeof(sign), &pos);
 	if (res != sizeof(sign))
 		goto write_error;
 
@@ -1010,9 +998,6 @@ void scst_pr_sync_device_file(struct scst_device *dev)
 
 	filp_close(file, NULL);
 
-out_set_fs:
-	set_fs(old_fs);
-
 out:
 	if (res != 0) {
 		PRINT_CRIT_ERROR("Unable to save persistent information "
@@ -1057,7 +1042,7 @@ write_error_close:
 				dev->pr_file_name, rc);
 	}
 #endif
-	goto out_set_fs;
+	goto out;
 }