silent truncation for large file offsets

Quoted 1 line

From a Linux client to a Linux server (in fact the same system in this

example), NFSv4.1, XFS file system:

root@vm:~/xfstests# truncate --size 9223372036854775807 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/nfs1/test
-rw-r--r-- 1 root root 9223372036854775806 Feb  8 18:30 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/test/test
-rw-r--r-- 1 root root 9223372036854775807 Feb  8 18:30 /mnt/test/test

so the file gets created with the correct size on the server, but the clients shows the size truncated.

This is extraced from xfstests generic/911 which tests clone functionality and fails because of this issue.

Quoted 12 lines · Christoph Hellwig

Quoted 1 line

From a Linux client to a Linux server (in fact the same system in this

example), NFSv4.1, XFS file system:

root@vm:~/xfstests# truncate --size 9223372036854775807 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/nfs1/test
-rw-r--r-- 1 root root 9223372036854775806 Feb  8 18:30 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/test/test
-rw-r--r-- 1 root root 9223372036854775807 Feb  8 18:30 /mnt/test/test

so the file gets created with the correct size on the server, but the clients shows the size truncated.

Quoted 2 lines

This is extraced from xfstests generic/911 which tests clone functionality and fails because of this issue.

Took a quick look at wireshark, and GETATTR is returning the correct (larger) size.

Also FSINFO (this is v3) returns 9223372036854775807 as the maximum file size.

Quoted 13 lines · J. Bruce Fields

Quoted 12 lines · Christoph Hellwig

Quoted 1 line

From a Linux client to a Linux server (in fact the same system in this

example), NFSv4.1, XFS file system:

root@vm:~/xfstests# truncate --size 9223372036854775807 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/nfs1/test
-rw-r--r-- 1 root root 9223372036854775806 Feb  8 18:30 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/test/test
-rw-r--r-- 1 root root 9223372036854775807 Feb  8 18:30 /mnt/test/test

so the file gets created with the correct size on the server, but the clients shows the size truncated.

Quoted 9 lines

Quoted 2 lines

This is extraced from xfstests generic/911 which tests clone functionality and fails because of this issue.

Took a quick look at wireshark, and GETATTR is returning the correct (larger) size.

Also FSINFO (this is v3) returns 9223372036854775807 as the maximum file size.

I'll bet it's this:

static inline loff_t nfs_size_to_loff_t(__u64 size)

{
        if (size > (__u64) OFFSET_MAX - 1)
                return OFFSET_MAX - 1;
        return (loff_t) size;
}

Should be "return OFFSET_MAX", no?

Quoted 33 lines · Trond Myklebust

Quoted 13 lines · J. Bruce Fields

Quoted 12 lines · Christoph Hellwig

Quoted 1 line

From a Linux client to a Linux server (in fact the same system in this

example), NFSv4.1, XFS file system:

root@vm:~/xfstests# truncate --size 9223372036854775807 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/nfs1/test
-rw-r--r-- 1 root root 9223372036854775806 Feb  8 18:30 /mnt/nfs1/test
root@vm:~/xfstests# ls -l /mnt/test/test
-rw-r--r-- 1 root root 9223372036854775807 Feb  8 18:30 /mnt/test/test

so the file gets created with the correct size on the server, but the clients shows the size truncated.

Quoted 9 lines

Quoted 2 lines

This is extraced from xfstests generic/911 which tests clone functionality and fails because of this issue.

Took a quick look at wireshark, and GETATTR is returning the correct (larger) size.

Also FSINFO (this is v3) returns 9223372036854775807 as the maximum file size.

I'll bet it's this:

static inline loff_t nfs_size_to_loff_t(__u64 size)

{
        if (size > (__u64) OFFSET_MAX - 1)
                return OFFSET_MAX - 1;
        return (loff_t) size;
}

Quoted 1 line

Should be "return OFFSET_MAX", no?

I guess so

(That's confusing, though--in general, shouldn't the maximum file size be one *more* than the maximum offset? But looks like st_size is off_t, so, I guess this is just how it is.)

I'll bet it's this:

static inline loff_t nfs_size_to_loff_t(__u64 size)

{
        if (size > (__u64) OFFSET_MAX - 1)
                return OFFSET_MAX - 1;
        return (loff_t) size;
}

Should be "return OFFSET_MAX", no?