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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-21 02:14:31 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-21 02:14:31 (GMT) |
commit | 1f0377ff088ed2971c57debc9b0c3b846ec431fd (patch) | |
tree | cd53c8981269e57e38e4285abd71cc990e1cfc67 /fs/fscache/page.c | |
parent | 54d46ea993744c5408e39ce0cb4851e13cbea716 (diff) | |
parent | b729d75d19777a5dd34672020516eada43ff026f (diff) | |
download | linux-fsl-qoriq-1f0377ff088ed2971c57debc9b0c3b846ec431fd.tar.xz |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS update from Al Viro:
"fscache fixes, ESTALE patchset, vmtruncate removal series, assorted
misc stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (79 commits)
vfs: make lremovexattr retry once on ESTALE error
vfs: make removexattr retry once on ESTALE
vfs: make llistxattr retry once on ESTALE error
vfs: make listxattr retry once on ESTALE error
vfs: make lgetxattr retry once on ESTALE
vfs: make getxattr retry once on an ESTALE error
vfs: allow lsetxattr() to retry once on ESTALE errors
vfs: allow setxattr to retry once on ESTALE errors
vfs: allow utimensat() calls to retry once on an ESTALE error
vfs: fix user_statfs to retry once on ESTALE errors
vfs: make fchownat retry once on ESTALE errors
vfs: make fchmodat retry once on ESTALE errors
vfs: have chroot retry once on ESTALE error
vfs: have chdir retry lookup and call once on ESTALE error
vfs: have faccessat retry once on an ESTALE error
vfs: have do_sys_truncate retry once on an ESTALE error
vfs: fix renameat to retry on ESTALE errors
vfs: make do_unlinkat retry once on ESTALE errors
vfs: make do_rmdir retry once on ESTALE errors
vfs: add a flags argument to user_path_parent
...
Diffstat (limited to 'fs/fscache/page.c')
-rw-r--r-- | fs/fscache/page.c | 195 |
1 files changed, 158 insertions, 37 deletions
diff --git a/fs/fscache/page.c b/fs/fscache/page.c index 3f7a59b..ff000e5 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -56,6 +56,7 @@ bool __fscache_maybe_release_page(struct fscache_cookie *cookie, _enter("%p,%p,%x", cookie, page, gfp); +try_again: rcu_read_lock(); val = radix_tree_lookup(&cookie->stores, page->index); if (!val) { @@ -104,11 +105,19 @@ bool __fscache_maybe_release_page(struct fscache_cookie *cookie, return true; page_busy: - /* we might want to wait here, but that could deadlock the allocator as - * the work threads writing to the cache may all end up sleeping - * on memory allocation */ - fscache_stat(&fscache_n_store_vmscan_busy); - return false; + /* We will wait here if we're allowed to, but that could deadlock the + * allocator as the work threads writing to the cache may all end up + * sleeping on memory allocation, so we may need to impose a timeout + * too. */ + if (!(gfp & __GFP_WAIT)) { + fscache_stat(&fscache_n_store_vmscan_busy); + return false; + } + + fscache_stat(&fscache_n_store_vmscan_wait); + __fscache_wait_on_page_write(cookie, page); + gfp &= ~__GFP_WAIT; + goto try_again; } EXPORT_SYMBOL(__fscache_maybe_release_page); @@ -162,6 +171,7 @@ static void fscache_attr_changed_op(struct fscache_operation *op) fscache_abort_object(object); } + fscache_op_complete(op, true); _leave(""); } @@ -223,6 +233,8 @@ static void fscache_release_retrieval_op(struct fscache_operation *_op) _enter("{OP%x}", op->op.debug_id); + ASSERTCMP(op->n_pages, ==, 0); + fscache_hist(fscache_retrieval_histogram, op->start_time); if (op->context) fscache_put_context(op->op.object->cookie, op->context); @@ -291,6 +303,17 @@ static int fscache_wait_for_deferred_lookup(struct fscache_cookie *cookie) } /* + * Handle cancellation of a pending retrieval op + */ +static void fscache_do_cancel_retrieval(struct fscache_operation *_op) +{ + struct fscache_retrieval *op = + container_of(_op, struct fscache_retrieval, op); + + op->n_pages = 0; +} + +/* * wait for an object to become active (or dead) */ static int fscache_wait_for_retrieval_activation(struct fscache_object *object, @@ -307,8 +330,8 @@ static int fscache_wait_for_retrieval_activation(struct fscache_object *object, fscache_stat(stat_op_waits); if (wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING, fscache_wait_bit_interruptible, - TASK_INTERRUPTIBLE) < 0) { - ret = fscache_cancel_op(&op->op); + TASK_INTERRUPTIBLE) != 0) { + ret = fscache_cancel_op(&op->op, fscache_do_cancel_retrieval); if (ret == 0) return -ERESTARTSYS; @@ -320,7 +343,14 @@ static int fscache_wait_for_retrieval_activation(struct fscache_object *object, _debug("<<< GO"); check_if_dead: + if (op->op.state == FSCACHE_OP_ST_CANCELLED) { + fscache_stat(stat_object_dead); + _leave(" = -ENOBUFS [cancelled]"); + return -ENOBUFS; + } if (unlikely(fscache_object_is_dead(object))) { + pr_err("%s() = -ENOBUFS [obj dead %d]\n", __func__, op->op.state); + fscache_cancel_op(&op->op, fscache_do_cancel_retrieval); fscache_stat(stat_object_dead); return -ENOBUFS; } @@ -353,6 +383,11 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, if (hlist_empty(&cookie->backing_objects)) goto nobufs; + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(page, !=, NULL); @@ -364,6 +399,7 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, _leave(" = -ENOMEM"); return -ENOMEM; } + op->n_pages = 1; spin_lock(&cookie->lock); @@ -375,10 +411,10 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, ASSERTCMP(object->state, >, FSCACHE_OBJECT_LOOKING_UP); atomic_inc(&object->n_reads); - set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); + __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); if (fscache_submit_op(object, &op->op) < 0) - goto nobufs_unlock; + goto nobufs_unlock_dec; spin_unlock(&cookie->lock); fscache_stat(&fscache_n_retrieval_ops); @@ -425,6 +461,8 @@ error: _leave(" = %d", ret); return ret; +nobufs_unlock_dec: + atomic_dec(&object->n_reads); nobufs_unlock: spin_unlock(&cookie->lock); kfree(op); @@ -472,6 +510,11 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, if (hlist_empty(&cookie->backing_objects)) goto nobufs; + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(*nr_pages, >, 0); ASSERT(!list_empty(pages)); @@ -482,6 +525,7 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, op = fscache_alloc_retrieval(mapping, end_io_func, context); if (!op) return -ENOMEM; + op->n_pages = *nr_pages; spin_lock(&cookie->lock); @@ -491,10 +535,10 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, struct fscache_object, cookie_link); atomic_inc(&object->n_reads); - set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); + __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); if (fscache_submit_op(object, &op->op) < 0) - goto nobufs_unlock; + goto nobufs_unlock_dec; spin_unlock(&cookie->lock); fscache_stat(&fscache_n_retrieval_ops); @@ -541,6 +585,8 @@ error: _leave(" = %d", ret); return ret; +nobufs_unlock_dec: + atomic_dec(&object->n_reads); nobufs_unlock: spin_unlock(&cookie->lock); kfree(op); @@ -577,12 +623,18 @@ int __fscache_alloc_page(struct fscache_cookie *cookie, ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); ASSERTCMP(page, !=, NULL); + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + if (fscache_wait_for_deferred_lookup(cookie) < 0) return -ERESTARTSYS; op = fscache_alloc_retrieval(page->mapping, NULL, NULL); if (!op) return -ENOMEM; + op->n_pages = 1; spin_lock(&cookie->lock); @@ -658,9 +710,27 @@ static void fscache_write_op(struct fscache_operation *_op) spin_lock(&object->lock); cookie = object->cookie; - if (!fscache_object_is_active(object) || !cookie) { + if (!fscache_object_is_active(object)) { + /* If we get here, then the on-disk cache object likely longer + * exists, so we should just cancel this write operation. + */ + spin_unlock(&object->lock); + fscache_op_complete(&op->op, false); + _leave(" [inactive]"); + return; + } + + if (!cookie) { + /* If we get here, then the cookie belonging to the object was + * detached, probably by the cookie being withdrawn due to + * memory pressure, which means that the pages we might write + * to the cache from no longer exist - therefore, we can just + * cancel this write operation. + */ spin_unlock(&object->lock); - _leave(""); + fscache_op_complete(&op->op, false); + _leave(" [cancel] op{f=%lx s=%u} obj{s=%u f=%lx}", + _op->flags, _op->state, object->state, object->flags); return; } @@ -696,6 +766,7 @@ static void fscache_write_op(struct fscache_operation *_op) fscache_end_page_write(object, page); if (ret < 0) { fscache_abort_object(object); + fscache_op_complete(&op->op, true); } else { fscache_enqueue_operation(&op->op); } @@ -710,6 +781,38 @@ superseded: spin_unlock(&cookie->stores_lock); clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); spin_unlock(&object->lock); + fscache_op_complete(&op->op, true); + _leave(""); +} + +/* + * Clear the pages pending writing for invalidation + */ +void fscache_invalidate_writes(struct fscache_cookie *cookie) +{ + struct page *page; + void *results[16]; + int n, i; + + _enter(""); + + while (spin_lock(&cookie->stores_lock), + n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, + ARRAY_SIZE(results), + FSCACHE_COOKIE_PENDING_TAG), + n > 0) { + for (i = n - 1; i >= 0; i--) { + page = results[i]; + radix_tree_delete(&cookie->stores, page->index); + } + + spin_unlock(&cookie->stores_lock); + + for (i = n - 1; i >= 0; i--) + page_cache_release(results[i]); + } + + spin_unlock(&cookie->stores_lock); _leave(""); } @@ -759,7 +862,12 @@ int __fscache_write_page(struct fscache_cookie *cookie, fscache_stat(&fscache_n_stores); - op = kzalloc(sizeof(*op), GFP_NOIO); + if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { + _leave(" = -ENOBUFS [invalidating]"); + return -ENOBUFS; + } + + op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY); if (!op) goto nomem; @@ -915,6 +1023,40 @@ done: EXPORT_SYMBOL(__fscache_uncache_page); /** + * fscache_mark_page_cached - Mark a page as being cached + * @op: The retrieval op pages are being marked for + * @page: The page to be marked + * + * Mark a netfs page as being cached. After this is called, the netfs + * must call fscache_uncache_page() to remove the mark. + */ +void fscache_mark_page_cached(struct fscache_retrieval *op, struct page *page) +{ + struct fscache_cookie *cookie = op->op.object->cookie; + +#ifdef CONFIG_FSCACHE_STATS + atomic_inc(&fscache_n_marks); +#endif + + _debug("- mark %p{%lx}", page, page->index); + if (TestSetPageFsCache(page)) { + static bool once_only; + if (!once_only) { + once_only = true; + printk(KERN_WARNING "FS-Cache:" + " Cookie type %s marked page %lx" + " multiple times\n", + cookie->def->name, page->index); + } + } + + if (cookie->def->mark_page_cached) + cookie->def->mark_page_cached(cookie->netfs_data, + op->mapping, page); +} +EXPORT_SYMBOL(fscache_mark_page_cached); + +/** * fscache_mark_pages_cached - Mark pages as being cached * @op: The retrieval op pages are being marked for * @pagevec: The pages to be marked @@ -925,32 +1067,11 @@ EXPORT_SYMBOL(__fscache_uncache_page); void fscache_mark_pages_cached(struct fscache_retrieval *op, struct pagevec *pagevec) { - struct fscache_cookie *cookie = op->op.object->cookie; unsigned long loop; -#ifdef CONFIG_FSCACHE_STATS - atomic_add(pagevec->nr, &fscache_n_marks); -#endif - - for (loop = 0; loop < pagevec->nr; loop++) { - struct page *page = pagevec->pages[loop]; - - _debug("- mark %p{%lx}", page, page->index); - if (TestSetPageFsCache(page)) { - static bool once_only; - if (!once_only) { - once_only = true; - printk(KERN_WARNING "FS-Cache:" - " Cookie type %s marked page %lx" - " multiple times\n", - cookie->def->name, page->index); - } - } - } + for (loop = 0; loop < pagevec->nr; loop++) + fscache_mark_page_cached(op, pagevec->pages[loop]); - if (cookie->def->mark_pages_cached) - cookie->def->mark_pages_cached(cookie->netfs_data, - op->mapping, pagevec); pagevec_reinit(pagevec); } EXPORT_SYMBOL(fscache_mark_pages_cached); |