/**
* nfs_can_coalesce_requests - test two requests for compatibility
* @prev: pointer to nfs_page
* @req: pointer to nfs_page
*
* The nfs_page structures 'prev' and 'req' are compared to ensure that the
* page data area they describe is contiguous, and that their RPC
* credentials, NFSv4 open state, and lockowners are the same.
*
* Return 'true' if this is the case, else return 'false'.
*/
static bool nfs_can_coalesce_requests(struct nfs_page *prev,
struct nfs_page *req,
struct nfs_pageio_descriptor *pgio)
{
size_t size;
if (prev) {
if (!nfs_match_open_context(req->wb_context, prev->wb_context))
return false;
if (req->wb_context->dentry->d_inode->i_flock != NULL &&
!nfs_match_lock_context(req->wb_lock_context,
prev->wb_lock_context))
return false;
if (req_offset(req) != req_offset(prev) + prev->wb_bytes)
return false;
if (req->wb_page == prev->wb_page) {
if (req->wb_pgbase != prev->wb_pgbase + prev->wb_bytes)
return false;
} else {
if (req->wb_pgbase != 0 ||
prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
return false;
}
}
size = pgio->pg_ops->pg_test(pgio, prev, req);
WARN_ON_ONCE(size > req->wb_bytes);
if (size && size < req->wb_bytes)
req->wb_bytes = size;
return size > 0;
}
/**
* nfs_can_coalesce_requests - test two requests for compatibility
* @prev: pointer to nfs_page
* @req: pointer to nfs_page
*
* The nfs_page structures 'prev' and 'req' are compared to ensure that the
* page data area they describe is contiguous, and that their RPC
* credentials, NFSv4 open state, and lockowners are the same.
*
* Return 'true' if this is the case, else return 'false'.
*/
static bool nfs_can_coalesce_requests(struct nfs_page *prev,
struct nfs_page *req,
struct nfs_pageio_descriptor *pgio)
{
if (!nfs_match_open_context(req->wb_context, prev->wb_context))
return false;
if (req->wb_context->dentry->d_inode->i_flock != NULL &&
!nfs_match_lock_context(req->wb_lock_context, prev->wb_lock_context))
return false;
if (req->wb_pgbase != 0)
return false;
if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
return false;
if (req_offset(req) != req_offset(prev) + prev->wb_bytes)
return false;
return pgio->pg_ops->pg_test(pgio, prev, req);
}
