Commit 032c09d7 authored by Hugh Dickins's avatar Hugh Dickins Committed by James Bottomley

[SCSI] sg and st unmap_user_pages allow PageReserved

2.6.15-rc1 made sg's st_unmap_user_pages and st's sgl_unmap_user_pages
BUG on a PageReserved page.  But that's wrong: they could be unmapping
the ZERO_PAGE, which is marked PG_reserved; and perhaps others (while
get_user_pages is still permitted on VM_PFNMAP areas - that may change).

More change is needed here: sg claims to dirty even pages written from,
and st claims not to dirty even pages read into; and SetPageDirty is not
adequate for this nowadays.  Fixes to those follow in a later patch: for
the moment just fix the 2.6.15 regression.
Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
Acked-by: default avatarNick Piggin <npiggin@suse.de>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 6bc733e9
...@@ -1878,8 +1878,6 @@ st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages, ...@@ -1878,8 +1878,6 @@ st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
for (i=0; i < nr_pages; i++) { for (i=0; i < nr_pages; i++) {
struct page *page = sgl[i].page; struct page *page = sgl[i].page;
/* XXX: just for debug. Remove when PageReserved is removed */
BUG_ON(PageReserved(page));
if (dirtied) if (dirtied)
SetPageDirty(page); SetPageDirty(page);
/* unlock_page(page); */ /* unlock_page(page); */
......
...@@ -4525,8 +4525,6 @@ static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_p ...@@ -4525,8 +4525,6 @@ static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_p
for (i=0; i < nr_pages; i++) { for (i=0; i < nr_pages; i++) {
struct page *page = sgl[i].page; struct page *page = sgl[i].page;
/* XXX: just for debug. Remove when PageReserved is removed */
BUG_ON(PageReserved(page));
if (dirtied) if (dirtied)
SetPageDirty(page); SetPageDirty(page);
/* FIXME: cache flush missing for rw==READ /* FIXME: cache flush missing for rw==READ
......
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