[XFS] Fixed a few bugs in xfs_buf_associate_memory()
- calculation of 'page_count' was incorrect as it did not consider the offset of 'mem' into the first page. The logic to bump 'page_count' didn't work if 'len' was <= PAGE_CACHE_SIZE (ie offset = 3k, len = 2k). - setting b_buffer_length to 'len' is incorrect if 'offset' is > 0. Set it to the total length of the buffer. - I suspect that passing a non-aligned address into mem_to_page() for the first page may have been causing issues - don't know but just tidy up that code anyway. SGI-PV: 971596 SGI-Modid: xfs-linux-melb:xfs-kern:30143a Signed-off-by: Lachlan McIlroy <lachlan@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org>
This commit is contained in:
parent
cd57e594ad
commit
d1afb678ce
|
@ -725,15 +725,15 @@ xfs_buf_associate_memory(
|
||||||
{
|
{
|
||||||
int rval;
|
int rval;
|
||||||
int i = 0;
|
int i = 0;
|
||||||
size_t ptr;
|
unsigned long pageaddr;
|
||||||
size_t end, end_cur;
|
unsigned long offset;
|
||||||
off_t offset;
|
size_t buflen;
|
||||||
int page_count;
|
int page_count;
|
||||||
|
|
||||||
page_count = PAGE_CACHE_ALIGN(len) >> PAGE_CACHE_SHIFT;
|
pageaddr = (unsigned long)mem & PAGE_CACHE_MASK;
|
||||||
offset = (off_t) mem - ((off_t)mem & PAGE_CACHE_MASK);
|
offset = (unsigned long)mem - pageaddr;
|
||||||
if (offset && (len > PAGE_CACHE_SIZE))
|
buflen = PAGE_CACHE_ALIGN(len + offset);
|
||||||
page_count++;
|
page_count = buflen >> PAGE_CACHE_SHIFT;
|
||||||
|
|
||||||
/* Free any previous set of page pointers */
|
/* Free any previous set of page pointers */
|
||||||
if (bp->b_pages)
|
if (bp->b_pages)
|
||||||
|
@ -747,22 +747,15 @@ xfs_buf_associate_memory(
|
||||||
return rval;
|
return rval;
|
||||||
|
|
||||||
bp->b_offset = offset;
|
bp->b_offset = offset;
|
||||||
ptr = (size_t) mem & PAGE_CACHE_MASK;
|
|
||||||
end = PAGE_CACHE_ALIGN((size_t) mem + len);
|
|
||||||
end_cur = end;
|
|
||||||
/* set up first page */
|
|
||||||
bp->b_pages[0] = mem_to_page(mem);
|
|
||||||
|
|
||||||
ptr += PAGE_CACHE_SIZE;
|
for (i = 0; i < bp->b_page_count; i++) {
|
||||||
bp->b_page_count = ++i;
|
bp->b_pages[i] = mem_to_page((void *)pageaddr);
|
||||||
while (ptr < end) {
|
pageaddr += PAGE_CACHE_SIZE;
|
||||||
bp->b_pages[i] = mem_to_page((void *)ptr);
|
|
||||||
bp->b_page_count = ++i;
|
|
||||||
ptr += PAGE_CACHE_SIZE;
|
|
||||||
}
|
}
|
||||||
bp->b_locked = 0;
|
bp->b_locked = 0;
|
||||||
|
|
||||||
bp->b_count_desired = bp->b_buffer_length = len;
|
bp->b_count_desired = len;
|
||||||
|
bp->b_buffer_length = buflen;
|
||||||
bp->b_flags |= XBF_MAPPED;
|
bp->b_flags |= XBF_MAPPED;
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
|
|
Loading…
Reference in New Issue