On Fri, Jun 16, 2017 at 04:51:20PM +0200, Andreas Gruenbacher wrote:
> (This patch is largely untested.)
In principle the XFS bits look ok, but I think you'd be better off with
a review from hch and, uh, while you wait, a run through the xfstests
'quota' group and probably 'auto' too?
I also think the two xfs patches would be better organized either as a
pair of patches where one patch gets rid of the __xfs_seek_hole_data
calls and the second removes the __xfs_seek_hole_data implementation;
or a single patch to refactor it out of xfs in a single blow.
--D
>
> Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
> ---
> fs/xfs/xfs_dquot.c | 5 +-
> fs/xfs/xfs_file.c | 320 -----------------------------------------------------
> fs/xfs/xfs_inode.h | 2 -
> 3 files changed, 3 insertions(+), 324 deletions(-)
>
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index 9d06cc3..a10bd921 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -39,6 +39,7 @@
> #include "xfs_trace.h"
> #include "xfs_log.h"
> #include "xfs_bmap_btree.h"
> +#include "xfs_iomap.h"
>
> /*
> * Lock order:
> @@ -726,8 +727,8 @@ xfs_dq_get_next_id(
> quotip = xfs_quota_inode(mp, type);
> lock = xfs_ilock_data_map_shared(quotip);
>
> - offset = __xfs_seek_hole_data(VFS_I(quotip), XFS_FSB_TO_B(mp, start),
> - eof, SEEK_DATA);
> + offset = __iomap_seek_hole_data(VFS_I(quotip), XFS_FSB_TO_B(mp, start), eof,
> + SEEK_DATA, &xfs_iomap_ops);
> if (offset < 0)
> error = offset;
>
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index b36dcd7..3acbbaf 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -953,326 +953,6 @@ xfs_file_readdir(
> return xfs_readdir(ip, ctx, bufsize);
> }
>
> -/*
> - * This type is designed to indicate the type of offset we would like
> - * to search from page cache for xfs_seek_hole_data().
> - */
> -enum {
> - HOLE_OFF = 0,
> - DATA_OFF,
> -};
> -
> -/*
> - * Lookup the desired type of offset from the given page.
> - *
> - * On success, return true and the offset argument will point to the
> - * start of the region that was found. Otherwise this function will
> - * return false and keep the offset argument unchanged.
> - */
> -STATIC bool
> -xfs_lookup_buffer_offset(
> - struct page *page,
> - loff_t *offset,
> - unsigned int type)
> -{
> - loff_t lastoff = page_offset(page);
> - bool found = false;
> - struct buffer_head *bh, *head;
> -
> - bh = head = page_buffers(page);
> - do {
> - /*
> - * Unwritten extents that have data in the page
> - * cache covering them can be identified by the
> - * BH_Unwritten state flag. Pages with multiple
> - * buffers might have a mix of holes, data and
> - * unwritten extents - any buffer with valid
> - * data in it should have BH_Uptodate flag set
> - * on it.
> - */
> - if (buffer_unwritten(bh) ||
> - buffer_uptodate(bh)) {
> - if (type == DATA_OFF)
> - found = true;
> - } else {
> - if (type == HOLE_OFF)
> - found = true;
> - }
> -
> - if (found) {
> - *offset = lastoff;
> - break;
> - }
> - lastoff += bh->b_size;
> - } while ((bh = bh->b_this_page) != head);
> -
> - return found;
> -}
> -
> -/*
> - * This routine is called to find out and return a data or hole offset
> - * from the page cache for unwritten extents according to the desired
> - * type for xfs_seek_hole_data().
> - *
> - * The argument offset is used to tell where we start to search from the
> - * page cache. Map is used to figure out the end points of the range to
> - * lookup pages.
> - *
> - * Return true if the desired type of offset was found, and the argument
> - * offset is filled with that address. Otherwise, return false and keep
> - * offset unchanged.
> - */
> -STATIC bool
> -xfs_find_get_desired_pgoff(
> - struct inode *inode,
> - struct xfs_bmbt_irec *map,
> - unsigned int type,
> - loff_t *offset)
> -{
> - struct xfs_inode *ip = XFS_I(inode);
> - struct xfs_mount *mp = ip->i_mount;
> - struct pagevec pvec;
> - pgoff_t index;
> - pgoff_t end;
> - loff_t endoff;
> - loff_t startoff = *offset;
> - loff_t lastoff = startoff;
> - bool found = false;
> -
> - pagevec_init(&pvec, 0);
> -
> - index = startoff >> PAGE_SHIFT;
> - endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
> - end = (endoff - 1) >> PAGE_SHIFT;
> - do {
> - int want;
> - unsigned nr_pages;
> - unsigned int i;
> -
> - want = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
> - nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
> - want);
> - if (nr_pages == 0)
> - break;
> -
> - for (i = 0; i < nr_pages; i++) {
> - struct page *page = pvec.pages[i];
> - loff_t b_offset;
> -
> - /*
> - * At this point, the page may be truncated or
> - * invalidated (changing page->mapping to NULL),
> - * or even swizzled back from swapper_space to tmpfs
> - * file mapping. However, page->index will not change
> - * because we have a reference on the page.
> - *
> - * If current page offset is beyond where we've ended,
> - * we've found a hole.
> - */
> - if (type == HOLE_OFF && lastoff < endoff &&
> - lastoff < page_offset(pvec.pages[i])) {
> - found = true;
> - *offset = lastoff;
> - goto out;
> - }
> - /* Searching done if the page index is out of range. */
> - if (page->index > end)
> - goto out;
> -
> - lock_page(page);
> - /*
> - * Page truncated or invalidated(page->mapping == NULL).
> - * We can freely skip it and proceed to check the next
> - * page.
> - */
> - if (unlikely(page->mapping != inode->i_mapping)) {
> - unlock_page(page);
> - continue;
> - }
> -
> - if (!page_has_buffers(page)) {
> - unlock_page(page);
> - continue;
> - }
> -
> - found = xfs_lookup_buffer_offset(page, &b_offset, type);
> - if (found) {
> - /*
> - * The found offset may be less than the start
> - * point to search if this is the first time to
> - * come here.
> - */
> - *offset = max_t(loff_t, startoff, b_offset);
> - unlock_page(page);
> - goto out;
> - }
> -
> - /*
> - * We either searching data but nothing was found, or
> - * searching hole but found a data buffer. In either
> - * case, probably the next page contains the desired
> - * things, update the last offset to it so.
> - */
> - lastoff = page_offset(page) + PAGE_SIZE;
> - unlock_page(page);
> - }
> -
> - /*
> - * The number of returned pages less than our desired, search
> - * done.
> - */
> - if (nr_pages < want)
> - break;
> -
> - index = pvec.pages[i - 1]->index + 1;
> - pagevec_release(&pvec);
> - } while (index <= end);
> -
> - /* No page at lastoff and we are not done - we found a hole. */
> - if (type == HOLE_OFF && lastoff < endoff) {
> - *offset = lastoff;
> - found = true;
> - }
> -out:
> - pagevec_release(&pvec);
> - return found;
> -}
> -
> -/*
> - * caller must lock inode with xfs_ilock_data_map_shared,
> - * can we craft an appropriate ASSERT?
> - *
> - * end is because the VFS-level lseek interface is defined such that any
> - * offset past i_size shall return -ENXIO, but we use this for quota code
> - * which does not maintain i_size, and we want to SEEK_DATA past i_size.
> - */
> -loff_t
> -__xfs_seek_hole_data(
> - struct inode *inode,
> - loff_t start,
> - loff_t end,
> - int whence)
> -{
> - struct xfs_inode *ip = XFS_I(inode);
> - struct xfs_mount *mp = ip->i_mount;
> - loff_t uninitialized_var(offset);
> - xfs_fileoff_t fsbno;
> - xfs_filblks_t lastbno;
> - int error;
> -
> - if (start >= end) {
> - error = -ENXIO;
> - goto out_error;
> - }
> -
> - /*
> - * Try to read extents from the first block indicated
> - * by fsbno to the end block of the file.
> - */
> - fsbno = XFS_B_TO_FSBT(mp, start);
> - lastbno = XFS_B_TO_FSB(mp, end);
> -
> - for (;;) {
> - struct xfs_bmbt_irec map[2];
> - int nmap = 2;
> - unsigned int i;
> -
> - error = xfs_bmapi_read(ip, fsbno, lastbno - fsbno, map, &nmap,
> - XFS_BMAPI_ENTIRE);
> - if (error)
> - goto out_error;
> -
> - /* No extents at given offset, must be beyond EOF */
> - if (nmap == 0) {
> - error = -ENXIO;
> - goto out_error;
> - }
> -
> - for (i = 0; i < nmap; i++) {
> - offset = max_t(loff_t, start,
> - XFS_FSB_TO_B(mp, map[i].br_startoff));
> -
> - /* Landed in the hole we wanted? */
> - if (whence == SEEK_HOLE &&
> - map[i].br_startblock == HOLESTARTBLOCK)
> - goto out;
> -
> - /* Landed in the data extent we wanted? */
> - if (whence == SEEK_DATA &&
> - (map[i].br_startblock == DELAYSTARTBLOCK ||
> - (map[i].br_state == XFS_EXT_NORM &&
> - !isnullstartblock(map[i].br_startblock))))
> - goto out;
> -
> - /*
> - * Landed in an unwritten extent, try to search
> - * for hole or data from page cache.
> - */
> - if (map[i].br_state == XFS_EXT_UNWRITTEN) {
> - if (xfs_find_get_desired_pgoff(inode, &map[i],
> - whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
> - &offset))
> - goto out;
> - }
> - }
> -
> - /*
> - * We only received one extent out of the two requested. This
> - * means we've hit EOF and didn't find what we are looking for.
> - */
> - if (nmap == 1) {
> - /*
> - * If we were looking for a hole, set offset to
> - * the end of the file (i.e., there is an implicit
> - * hole at the end of any file).
> - */
> - if (whence == SEEK_HOLE) {
> - offset = end;
> - break;
> - }
> - /*
> - * If we were looking for data, it's nowhere to be found
> - */
> - ASSERT(whence == SEEK_DATA);
> - error = -ENXIO;
> - goto out_error;
> - }
> -
> - ASSERT(i > 1);
> -
> - /*
> - * Nothing was found, proceed to the next round of search
> - * if the next reading offset is not at or beyond EOF.
> - */
> - fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
> - start = XFS_FSB_TO_B(mp, fsbno);
> - if (start >= end) {
> - if (whence == SEEK_HOLE) {
> - offset = end;
> - break;
> - }
> - ASSERT(whence == SEEK_DATA);
> - error = -ENXIO;
> - goto out_error;
> - }
> - }
> -
> -out:
> - /*
> - * If at this point we have found the hole we wanted, the returned
> - * offset may be bigger than the file size as it may be aligned to
> - * page boundary for unwritten extents. We need to deal with this
> - * situation in particular.
> - */
> - if (whence == SEEK_HOLE)
> - offset = min_t(loff_t, offset, end);
> -
> - return offset;
> -
> -out_error:
> - return error;
> -}
> -
> STATIC loff_t
> xfs_seek_hole_data(
> struct file *file,
> diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
> index 10e89fc..17c441a 100644
> --- a/fs/xfs/xfs_inode.h
> +++ b/fs/xfs/xfs_inode.h
> @@ -445,8 +445,6 @@ int xfs_zero_eof(struct xfs_inode *ip, xfs_off_t offset,
> xfs_fsize_t isize, bool *did_zeroing);
> int xfs_zero_range(struct xfs_inode *ip, xfs_off_t pos, xfs_off_t count,
> bool *did_zero);
> -loff_t __xfs_seek_hole_data(struct inode *inode, loff_t start,
> - loff_t eof, int whence);
>
>
> /* from xfs_iops.c */
> --
> 2.7.5
>
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