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3325b4d857
The s390_hypfs filesystem is deprecated and shouldn't be used due to its rather odd semantics. It creates a whole directory structure with static file contents so a user can read a consistent state while within that directory. Writing to its update attribute will remove and rebuild nearly the whole filesystem, so that again a user can read a consistent state, even if multiple files need to be read. Given that this wastes a lot of CPU cycles, and involves a lot of code, binary interfaces have been added quite a couple of years ago, which simply pass the binary data to user space, and let user space decode the data. This is the preferred and only way how the data should be retrieved. The assumption is that there are no users of the s390_hypfs filesystem. However instead of just removing the code, and having to revert in case there are actually users, factor the filesystem code out and make it only available via a new config option. This config option is supposed to be disabled. If it turns out there are no complaints the filesystem code can be removed probably in a couple of years. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
36 lines
805 B
C
36 lines
805 B
C
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Hypervisor filesystem for Linux on s390. Diag 204 and 224
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* implementation.
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*
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* Copyright IBM Corp. 2006, 2008
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* Author(s): Michael Holzheu <holzheu@de.ibm.com>
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*/
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#ifndef _S390_HYPFS_DIAG_H_
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#define _S390_HYPFS_DIAG_H_
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#include <asm/diag.h>
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enum diag204_format diag204_get_info_type(void);
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void *diag204_get_buffer(enum diag204_format fmt, int *pages);
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int diag204_store(void *buf, int pages);
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int __hypfs_diag_fs_init(void);
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void __hypfs_diag_fs_exit(void);
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static inline int hypfs_diag_fs_init(void)
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{
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if (IS_ENABLED(CONFIG_S390_HYPFS_FS))
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return __hypfs_diag_fs_init();
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return 0;
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}
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static inline void hypfs_diag_fs_exit(void)
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{
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if (IS_ENABLED(CONFIG_S390_HYPFS_FS))
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__hypfs_diag_fs_exit();
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}
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#endif /* _S390_HYPFS_DIAG_H_ */
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