在 2025/6/14 09:05, Qu Wenruo 写道:
在 2025/6/14 04:37, Matthew Wilcox (Oracle) 写道:
Replace the 'page' variable with 'folio'. Removes six calls to
compound_head().
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
fs/btrfs/tests/extent-io-tests.c | 32 +++++++++++++++++---------------
1 file changed, 17 insertions(+), 15 deletions(-)
diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-
io-tests.c
index 8bdf742d90fd..36720b77b440 100644
--- a/fs/btrfs/tests/extent-io-tests.c
+++ b/fs/btrfs/tests/extent-io-tests.c
@@ -111,7 +111,7 @@ static int test_find_delalloc(u32 sectorsize, u32
nodesize)
struct btrfs_root *root = NULL;
struct inode *inode = NULL;
struct extent_io_tree *tmp;
- struct page *page;
+ struct folio *folio;
struct folio *locked_folio = NULL;
unsigned long index = 0;
/* In this test we need at least 2 file extents at its maximum
size */
@@ -152,23 +152,25 @@ static int test_find_delalloc(u32 sectorsize,
u32 nodesize)
btrfs_extent_io_tree_init(NULL, tmp, IO_TREE_SELFTEST);
/*
- * First go through and create and mark all of our pages dirty,
we pin
- * everything to make sure our pages don't get evicted and screw
up our
+ * First go through and create and mark all of our folios dirty,
we pin
+ * everything to make sure our folios don't get evicted and screw
up our
* test.
*/
for (index = 0; index < (total_dirty >> PAGE_SHIFT); index++) {
- page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
- if (!page) {
- test_err("failed to allocate test page");
+ folio = __filemap_get_folio(inode->i_mapping, index,
+ FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
+ GFP_KERNEL);
+ if (!folio) {
+ test_err("failed to allocate test folio");
ret = -ENOMEM;
goto out;
}
- SetPageDirty(page);
+ folio_mark_dirty(folio);
Crashing immediately when loading the module.
(Need CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y)
[ 20.626710] BUG: kernel NULL pointer dereference, address:
0000000000000000
This is from the a_ops, which is NULL for testing inodes.
So here we should not call folio_mark_dirty(), as it will call
dirty_folio() callbacks unconditionally no matter if the mapping has
such call backs.
Instead we should call noop_dirty_folio() instead, which is the
equivalent of SetPageDirty().
Thanks,
Qu
[ 20.628812] #PF: supervisor instruction fetch in kernel mode
[ 20.630648] #PF: error_code(0x0010) - not-present page
[ 20.632156] PGD 0 P4D 0
[ 20.632893] Oops: Oops: 0010 [#1] SMP NOPTI
[ 20.634052] CPU: 6 UID: 0 PID: 622 Comm: insmod Tainted: G OE
6.16.0-rc1-custom+ #253 PREEMPT(full)
[ 20.636879] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[ 20.638321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
unknown 02/02/2022
[ 20.640524] RIP: 0010:0x0
[ 20.641290] Code: Unable to access opcode bytes at 0xffffffffffffffd6.
[ 20.643075] RSP: 0018:ffffc90001587c88 EFLAGS: 00010246
[ 20.644519] RAX: ffff88810b144670 RBX: 0000000000000000 RCX:
0000000000000001
[ 20.646490] RDX: 0000000000000000 RSI: ffffea0004128200 RDI:
ffff88810b144670
[ 20.648496] RBP: ffff88810b144500 R08: 0000000000000000 R09:
ffffffff83549b20
[ 20.650524] R10: 00000000000002c0 R11: 0000000000000000 R12:
0000000000000000
[ 20.652642] R13: ffff88810b1443a8 R14: ffffea0004128200 R15:
0000000000001000
[ 20.654778] FS: 00007f2e60e99740(0000) GS:ffff8882f45e2000(0000)
knlGS:0000000000000000
[ 20.657158] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 20.658980] CR2: ffffffffffffffd6 CR3: 00000001040b9000 CR4:
00000000000006f0
[ 20.661219] Call Trace:
[ 20.662057] <TASK>
[ 20.662757] btrfs_test_extent_io+0x17a/0xf40 [btrfs]
[ 20.664266] btrfs_run_sanity_tests.cold+0x84/0x11e [btrfs]
[ 20.665839] init_btrfs_fs+0x4d/0xb0 [btrfs]
[ 20.667380] ? __pfx_init_btrfs_fs+0x10/0x10 [btrfs]
[ 20.668883] do_one_initcall+0x76/0x250
[ 20.670098] do_init_module+0x62/0x250
[ 20.671359] init_module_from_file+0x85/0xc0
[ 20.672586] idempotent_init_module+0x148/0x340
[ 20.673900] __x64_sys_finit_module+0x6d/0xd0
[ 20.675074] do_syscall_64+0x54/0x1d0
[ 20.676167] entry_SYSCALL_64_after_hwframe+0x76/0x7e
Furthermore, the error handling of __filemap_get_folio() is incorrect.
That function returns either a valid folio, or an ERR_PTR(), no more NULL.
This applies to all folio calls like filemap_lock_folio() too.
Thanks,
Qu
if (index) {
- unlock_page(page);
+ folio_unlock(folio);
} else {
- get_page(page);
- locked_folio = page_folio(page);
+ folio_get(folio);
+ locked_folio = folio;
}
}
@@ -283,14 +285,14 @@ static int test_find_delalloc(u32 sectorsize,
u32 nodesize)
* Now to test where we run into a page that is no longer dirty
in the
* range we want to find.
*/
- page = find_get_page(inode->i_mapping,
+ folio = filemap_get_folio(inode->i_mapping,
(max_bytes + SZ_1M) >> PAGE_SHIFT);
- if (!page) {
- test_err("couldn't find our page");
+ if (!folio) {
+ test_err("couldn't find our folio");
goto out_bits;
}
- ClearPageDirty(page);
- put_page(page);
+ folio_clear_dirty(folio);
+ folio_put(folio);
/* We unlocked it in the previous test */
folio_lock(locked_folio);
