[LU-19255] mirror write functions should not round up bytes to write(!)

• Type: Bug
• Resolution: Unresolved
• Priority: Medium
• Severity: 3
• Assignee: Patrick Farrell
• Reporter: Patrick Farrell

Description

The functions:

lfs_mirror_write
llapi_mirror_copy
llapi_mirror_copy_many
llapi_mirror_resync_many_params 

All share the same mistake, rounding up the number of bytes to write before writing out:

/* round up to page align to make direct IO happy. */
to_write = ((bytes_read - 1) | (page_size - 1)) + 1; 

I noticed this when playing with them - copying a small input file, they round up the size to 4K and put junk padding in.

I'll push a patch and try to include some tests.