Re: [PATCH v5 33/40] netfs, cachefiles: Pass upper bound length to allow expansion

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Tested-by: Yiqun Leng <yqleng@xxxxxxxxxxxxxxxxx>

Please get more test details in this link: https://tone.openanolis.cn/ws/nrh4nnio/test_result/106066

Thanks and Regards,
Yiqun Leng


On 2024/1/3 04:37, Gao Xiang wrote:


On 2024/1/3 01:11, David Howells wrote:
Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx> wrote:

       down = start - round_down(start, PAGE_SIZE);
       *_start = start - down;
       *_len = round_up(down + len, PAGE_SIZE);
+    if (down < start || *_len > upper_len)
+        return -ENOBUFS;

Sorry for bothering. We just found some strange when testing
today-next EROFS over fscache.

I'm not sure the meaning of
     if (down < start

For example, if start is page-aligned, down == 0.

so as long as start > 0 and page-aligned, it will return
-ENOBUFS.  Does it an intended behavior?

Yeah, I think that's wrong.

Does the attached help?

(+cc more people for testing)

Will test and feedback later.

Thanks,
Gao Xiang


David
---

diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index bffffedce4a9..7529b40bc95a 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -522,16 +522,22 @@ int __cachefiles_prepare_write(struct cachefiles_object *object,
                     bool no_space_allocated_yet)
  {
      struct cachefiles_cache *cache = object->volume->cache;
-    loff_t start = *_start, pos;
-    size_t len = *_len, down;
+    unsigned long long start = *_start, pos;
+    size_t len = *_len;
      int ret;
        /* Round to DIO size */
-    down = start - round_down(start, PAGE_SIZE);
-    *_start = start - down;
-    *_len = round_up(down + len, PAGE_SIZE);
-    if (down < start || *_len > upper_len)
+    start = round_down(*_start, PAGE_SIZE);
+    if (start != *_start) {
+        kleave(" = -ENOBUFS [down]");
+        return -ENOBUFS;
+    }
+    if (*_len > upper_len) {
+        kleave(" = -ENOBUFS [up]");
          return -ENOBUFS;
+    }
+
+    *_len = round_up(len, PAGE_SIZE);
        /* We need to work out whether there's sufficient disk space to perform
       * the write - but we can skip that check if we have space already
@@ -542,7 +548,7 @@ int __cachefiles_prepare_write(struct cachefiles_object *object,
        pos = cachefiles_inject_read_error();
      if (pos == 0)
-        pos = vfs_llseek(file, *_start, SEEK_DATA);
+        pos = vfs_llseek(file, start, SEEK_DATA);
      if (pos < 0 && pos >= (loff_t)-MAX_ERRNO) {
          if (pos == -ENXIO)
              goto check_space; /* Unallocated tail */
@@ -550,7 +556,7 @@ int __cachefiles_prepare_write(struct cachefiles_object *object,
                        cachefiles_trace_seek_error);
          return pos;
      }
-    if ((u64)pos >= (u64)*_start + *_len)
+    if (pos >= start + *_len)
          goto check_space; /* Unallocated region */
        /* We have a block that's at least partially filled - if we're low on
@@ -563,13 +569,13 @@ int __cachefiles_prepare_write(struct cachefiles_object *object,
        pos = cachefiles_inject_read_error();
      if (pos == 0)
-        pos = vfs_llseek(file, *_start, SEEK_HOLE);
+        pos = vfs_llseek(file, start, SEEK_HOLE);
      if (pos < 0 && pos >= (loff_t)-MAX_ERRNO) {
          trace_cachefiles_io_error(object, file_inode(file), pos,
                        cachefiles_trace_seek_error);
          return pos;
      }
-    if ((u64)pos >= (u64)*_start + *_len)
+    if (pos >= start + *_len)
          return 0; /* Fully allocated */
        /* Partially allocated, but insufficient space: cull. */
@@ -577,7 +583,7 @@ int __cachefiles_prepare_write(struct cachefiles_object *object,
      ret = cachefiles_inject_remove_error();
      if (ret == 0)
          ret = vfs_fallocate(file, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
-                    *_start, *_len);
+                    start, *_len);
      if (ret < 0) {
          trace_cachefiles_io_error(object, file_inode(file), ret,
                        cachefiles_trace_fallocate_error);



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux