cifs: abstract out function to marshal up the iovec array for async writes

We'll need to do something a bit different depending on the caller.
Abstract the code that marshals the page array into an iovec.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
This commit is contained in:
Jeff Layton 2012-03-23 14:40:56 -04:00
parent a7103b99e4
commit e9492871fb
3 changed files with 31 additions and 10 deletions

View File

@ -490,6 +490,8 @@ struct cifs_writedata {
pid_t pid;
unsigned int bytes;
int result;
void (*marshal_iov) (struct kvec *iov,
struct cifs_writedata *wdata);
unsigned int nr_pages;
struct page *pages[1];
};

View File

@ -2142,7 +2142,6 @@ cifs_async_writev(struct cifs_writedata *wdata)
WRITE_REQ *smb = NULL;
int wct;
struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
struct inode *inode = wdata->cfile->dentry->d_inode;
struct kvec *iov = NULL;
if (tcon->ses->capabilities & CAP_LARGE_FILES) {
@ -2185,15 +2184,13 @@ cifs_async_writev(struct cifs_writedata *wdata)
iov[0].iov_len = be32_to_cpu(smb->hdr.smb_buf_length) + 4 + 1;
iov[0].iov_base = smb;
/* marshal up the pages into iov array */
wdata->bytes = 0;
for (i = 0; i < wdata->nr_pages; i++) {
iov[i + 1].iov_len = min(inode->i_size -
page_offset(wdata->pages[i]),
(loff_t)PAGE_CACHE_SIZE);
iov[i + 1].iov_base = kmap(wdata->pages[i]);
wdata->bytes += iov[i + 1].iov_len;
}
/*
* This function should marshal up the page array into the kvec
* array, reserving [0] for the header. It should kmap the pages
* and set the iov_len properly for each one. It may also set
* wdata->bytes too.
*/
wdata->marshal_iov(iov, wdata);
cFYI(1, "async write at %llu %u bytes", wdata->offset, wdata->bytes);

View File

@ -1648,6 +1648,27 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
return rc;
}
/*
* Marshal up the iov array, reserving the first one for the header. Also,
* set wdata->bytes.
*/
static void
cifs_writepages_marshal_iov(struct kvec *iov, struct cifs_writedata *wdata)
{
int i;
struct inode *inode = wdata->cfile->dentry->d_inode;
loff_t size = i_size_read(inode);
/* marshal up the pages into iov array */
wdata->bytes = 0;
for (i = 0; i < wdata->nr_pages; i++) {
iov[i + 1].iov_len = min(size - page_offset(wdata->pages[i]),
(loff_t)PAGE_CACHE_SIZE);
iov[i + 1].iov_base = kmap(wdata->pages[i]);
wdata->bytes += iov[i + 1].iov_len;
}
}
static int cifs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
@ -1792,6 +1813,7 @@ retry:
wdata->sync_mode = wbc->sync_mode;
wdata->nr_pages = nr_pages;
wdata->offset = page_offset(wdata->pages[0]);
wdata->marshal_iov = cifs_writepages_marshal_iov;
do {
if (wdata->cfile != NULL)