If a particular fallocate mode is causing test failures, give the tester the ability to block a particular fallocate mode so that the use of a particular fallocate mode will be reported as not supported. For example, if the COLLAPSE_RANGE fallocate mode is causing test failures, this allows us to suppress it so we can more easily test the rest of the file system code. Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx> --- fs/ext4/extents.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 64b4003..1bb3e4b 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -29,6 +29,7 @@ * - smart tree reduction */ +#include <linux/module.h> #include <linux/fs.h> #include <linux/time.h> #include <linux/jbd2.h> @@ -4862,6 +4863,12 @@ out_mutex: return ret; } +int ext4_fallocate_mode_block __read_mostly; + +module_param_named(fallocate_mode_block, ext4_fallocate_mode_block, int, 0644); +MODULE_PARM_DESC(fallocate_mode_block, + "Fallocate modes which are blocked for debugging purposes"); + /* * preallocate space for a file. This implements ext4's fallocate file * operation, which gets called from sys_fallocate system call. @@ -4881,6 +4888,13 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) struct timespec tv; unsigned int blkbits = inode->i_blkbits; + /* + * for debugging purposes, allow certain fallocate operations + * to be disabled + */ + if (unlikely(mode & ext4_fallocate_mode_block)) + return -EOPNOTSUPP; + /* Return error if mode is not supported */ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)) -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
