PG_fscache is going to be used to indicate that a page is being written to the cache, and that the page should not be modified or released until it's finished. Make afs_invalidatepage() and afs_releasepage() wait for it. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: linux-afs@xxxxxxxxxxxxxxxxxxx cc: linux-cachefs@xxxxxxxxxx cc: linux-fsdevel@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/158861253957.340223.7465334678444521655.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # rfc Link: https://lore.kernel.org/r/159465832417.1377938.3571599385208729791.stgit@xxxxxxxxxxxxxxxxxxxxxx/ Link: https://lore.kernel.org/r/160588536286.3465195.13231895135369807920.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # rfc Link: https://lore.kernel.org/r/161118153708.1232039.3535103645871176749.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # rfc Link: https://lore.kernel.org/r/161161049369.2537118.11591934943429117060.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v2 Link: https://lore.kernel.org/r/161340412903.1303470.6424701655031380012.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v3 Link: https://lore.kernel.org/r/161539556890.286939.5873470593519458598.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v4 Link: https://lore.kernel.org/r/161653812726.2770958.18167145829938766503.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v5 --- fs/afs/file.c | 9 +++++++++ fs/afs/write.c | 10 ++++++++++ 2 files changed, 19 insertions(+) diff --git a/fs/afs/file.c b/fs/afs/file.c index 4a34ffaf6de4..f1e30b89e41c 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -593,6 +593,7 @@ static void afs_invalidatepage(struct page *page, unsigned int offset, if (PagePrivate(page)) afs_invalidate_dirty(page, offset, length); + wait_on_page_fscache(page); _leave(""); } @@ -610,6 +611,14 @@ static int afs_releasepage(struct page *page, gfp_t gfp_flags) /* deny if page is being written to the cache and the caller hasn't * elected to wait */ +#ifdef CONFIG_AFS_FSCACHE + if (PageFsCache(page)) { + if (!(gfp_flags & __GFP_DIRECT_RECLAIM) || !(gfp_flags & __GFP_FS)) + return false; + wait_on_page_fscache(page); + } +#endif + if (PagePrivate(page)) { detach_page_private(page); trace_afs_page_dirty(vnode, tracepoint_string("rel"), page); diff --git a/fs/afs/write.c b/fs/afs/write.c index 6e41b982c71b..1b8cabf5ac92 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -117,6 +117,10 @@ int afs_write_begin(struct file *file, struct address_space *mapping, SetPageUptodate(page); } +#ifdef CONFIG_AFS_FSCACHE + wait_on_page_fscache(page); +#endif + try_again: /* See if this page is already partially written in a way that we can * merge the new write with. @@ -857,6 +861,11 @@ vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) /* Wait for the page to be written to the cache before we allow it to * be modified. We then assume the entire page will need writing back. */ +#ifdef CONFIG_AFS_FSCACHE + if (PageFsCache(vmf->page) && + wait_on_page_bit_killable(vmf->page, PG_fscache) < 0) + return VM_FAULT_RETRY; +#endif if (wait_on_page_writeback_killable(vmf->page)) return VM_FAULT_RETRY; @@ -947,5 +956,6 @@ int afs_launder_page(struct page *page) detach_page_private(page); trace_afs_page_dirty(vnode, tracepoint_string("laundered"), page); + wait_on_page_fscache(page); return ret; }
