[LTP] [PATCH v2 1/2] libswap: Add {SAFE_, }MAKE_MINIMAL_SWAPFILE() macros

[Petr Vorel]

65536 bytes triggered warning on systems with 64kb page size (e.g. on
aarch64 with CONFIG_ARM64_64K_PAGES=y or on ppc64le with
CONFIG_PAGE_SIZE_64KB=y):

    TWARN: Swapfile size is less than the system page size. Using page size
    (65536 bytes) instead of block size (4096 bytes).

1 MB should be ok for most of the systems.

Suggested-by: Cyril Hrubis <chrubis@suse.cz>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
Changes v1->v2:
* Use 1MB for minimal swap file instead of using disk block size as a
  base measure of size (Cyril)

 include/libswap.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/libswap.h b/include/libswap.h
index 87e32328e..28ce7842d 100644
--- a/include/libswap.h
+++ b/include/libswap.h
@@ -23,6 +23,24 @@ int make_swapfile(const char *file, const int lineno,
 			const char *swapfile, unsigned int num,
 			int safe, enum swapfile_method method);
 
+/* 65536 bytes is minimum for 64kb page size, let's use 1 MB */
+#define MINIMAL_SWAP_SIZE_MB 1
+
+/**
+ * Macro to create minimal swapfile.
+ */
+#define MAKE_MINIMAL_SWAPFILE(swapfile) \
+    make_swapfile(__FILE__, __LINE__, swapfile, MINIMAL_SWAP_SIZE_MB, 0, \
+		  SWAPFILE_BY_SIZE)
+
+/**
+ * Macro to create minimal swapfile.
+ * Includes safety checks to handle potential errors.
+ */
+#define SAFE_MAKE_MINIMAL_SWAPFILE(swapfile) \
+    make_swapfile(__FILE__, __LINE__, swapfile, MINIMAL_SWAP_SIZE_MB, 1, \
+		  SWAPFILE_BY_SIZE)
+
 /**
  * Macro to create swapfile size in megabytes (MB).
  */
-- 
2.43.0