Hi Chao,
On 2019/1/26 10:48, Chao Yu wrote:
> On 2019/1/26 0:10, Gao Xiang wrote:
>> Let's add .get_acl() to read the file's acl from its xattrs
>> to make POSIX ACL usable.
>>
>> Here is the on-disk detail,
>> fullname: system.posix_acl_access
>> struct erofs_xattr_entry:
>> .e_name_len = 0
>> .e_name_index = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS (2)
>>
>> fullname: system.posix_acl_default
>> struct erofs_xattr_entry:
>> .e_name_len = 0
>> .e_name_index = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT (3)
>>
>> Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
>> ---
>> change log v2:
>> - add the missing SB_POSIXACL flag;
>> - fix the on-disk detail, use .e_name_len == 0 and proper prefix value;
>> - tested ok with xattr enabled erofs_mkfs;
>>
>> .../erofs/Documentation/filesystems/erofs.txt | 2 ++
>> drivers/staging/erofs/inode.c | 3 ++
>> drivers/staging/erofs/namei.c | 1 +
>> drivers/staging/erofs/super.c | 8 +++++
>> drivers/staging/erofs/xattr.c | 37 ++++++++++++++++++++++
>> drivers/staging/erofs/xattr.h | 6 ++++
>> 6 files changed, 57 insertions(+)
>>
>> diff --git a/drivers/staging/erofs/Documentation/filesystems/erofs.txt b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
>> index 803988d74c21..961ec4da7705 100644
>> --- a/drivers/staging/erofs/Documentation/filesystems/erofs.txt
>> +++ b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
>> @@ -36,6 +36,8 @@ Here is the main features of EROFS:
>>
>> - Support xattr inline and tail-end data inline for all files;
>>
>> + - Support POSIX.1e ACLs by using xattrs;
>> +
>> - Support transparent file compression as an option:
>> LZ4 algorithm with 4 KB fixed-output compression for high performance;
>>
>> diff --git a/drivers/staging/erofs/inode.c b/drivers/staging/erofs/inode.c
>> index 4f04f7c38cf2..924b8dfc7a8f 100644
>> --- a/drivers/staging/erofs/inode.c
>> +++ b/drivers/staging/erofs/inode.c
>> @@ -287,6 +287,7 @@ const struct inode_operations erofs_generic_iops = {
>> #ifdef CONFIG_EROFS_FS_XATTR
>> .listxattr = erofs_listxattr,
>> #endif
>> + .get_acl = erofs_get_acl,
>> };
>>
>> const struct inode_operations erofs_symlink_iops = {
>> @@ -294,6 +295,7 @@ const struct inode_operations erofs_symlink_iops = {
>> #ifdef CONFIG_EROFS_FS_XATTR
>> .listxattr = erofs_listxattr,
>> #endif
>> + .get_acl = erofs_get_acl,
>> };
>>
>> const struct inode_operations erofs_fast_symlink_iops = {
>> @@ -301,5 +303,6 @@ const struct inode_operations erofs_fast_symlink_iops = {
>> #ifdef CONFIG_EROFS_FS_XATTR
>> .listxattr = erofs_listxattr,
>> #endif
>> + .get_acl = erofs_get_acl,
>> };
>>
>> diff --git a/drivers/staging/erofs/namei.c b/drivers/staging/erofs/namei.c
>> index 7fed1f996ab0..b1752adc5934 100644
>> --- a/drivers/staging/erofs/namei.c
>> +++ b/drivers/staging/erofs/namei.c
>> @@ -238,5 +238,6 @@ const struct inode_operations erofs_dir_iops = {
>> #ifdef CONFIG_EROFS_FS_XATTR
>> .listxattr = erofs_listxattr,
>> #endif
>> + .get_acl = erofs_get_acl,
>> };
>>
>> diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
>> index 176fca2af379..54cd7dac0a1f 100644
>> --- a/drivers/staging/erofs/super.c
>> +++ b/drivers/staging/erofs/super.c
>> @@ -398,6 +398,14 @@ static int erofs_read_super(struct super_block *sb,
>> if (!silent)
>> infoln("root inode @ nid %llu", ROOT_NID(sbi));
>>
>> +#ifdef CONFIG_EROFS_FS_POSIX_ACL
>> + /* Update the POSIXACL Flag */
>> + if (test_opt(sbi, POSIX_ACL))
>> + sb->s_flags |= SB_POSIXACL;
>> + else
>> + sb->s_flags &= ~SB_POSIXACL;
>> +#endif
>> +
>> #ifdef CONFIG_EROFS_FS_ZIP
>> INIT_RADIX_TREE(&sbi->workstn_tree, GFP_ATOMIC);
>> #endif
>> diff --git a/drivers/staging/erofs/xattr.c b/drivers/staging/erofs/xattr.c
>> index 7de46690d972..6759485ae862 100644
>> --- a/drivers/staging/erofs/xattr.c
>> +++ b/drivers/staging/erofs/xattr.c
>> @@ -643,3 +643,40 @@ ssize_t erofs_listxattr(struct dentry *dentry,
>> return shared_listxattr(&it);
>> }
>>
>> +#ifdef CONFIG_EROFS_FS_POSIX_ACL
>> +struct posix_acl *erofs_get_acl(struct inode *inode, int type)
>> +{
>> + struct posix_acl *acl;
>> + int ea_prefix, rc;
>> + char *value = NULL;
>> +
>> + switch(type) {
>> + case ACL_TYPE_ACCESS:
>> + ea_prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS;
>> + break;
>> + case ACL_TYPE_DEFAULT:
>> + ea_prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT;
>> + break;
>> + default:
>> + return ERR_PTR(-EINVAL);
>> + }
>> +
>> + rc = erofs_getxattr(inode, ea_prefix, "", NULL, 0);
>> + if (rc > 0) {
>> + value = kvmalloc(rc, GFP_KERNEL);
>
> erofs_kmalloc() is enough?
I think kmalloc is enough for this case, but I think kvmalloc is not
bad as well.
Actually I want to introduce erofs_kvmalloc() in the later patch and
use it in general except for the context which is unsuitable for vmalloc..
Let me send v3 if it is unnecessary...
Thanks,
Gao Xiang
>
> Thanks,
>
>> + if (!value)
>> + return ERR_PTR(-ENOMEM);
>> + rc = erofs_getxattr(inode, ea_prefix, "", value, rc);
>> + }
>> +
>> + if (rc == -ENOATTR)
>> + acl = NULL;
>> + else if (rc < 0)
>> + acl = ERR_PTR(rc);
>> + else
>> + acl = posix_acl_from_xattr(&init_user_ns, value, rc);
>> + kvfree(value);
>> + return acl;
>> +}
>> +#endif
>> +
>> diff --git a/drivers/staging/erofs/xattr.h b/drivers/staging/erofs/xattr.h
>> index 634dae9aaa0b..35ba5ac2139a 100644
>> --- a/drivers/staging/erofs/xattr.h
>> +++ b/drivers/staging/erofs/xattr.h
>> @@ -87,5 +87,11 @@ static ssize_t __maybe_unused erofs_listxattr(struct dentry *dentry,
>> }
>> #endif
>>
>> +#ifdef CONFIG_EROFS_FS_POSIX_ACL
>> +struct posix_acl *erofs_get_acl(struct inode *inode, int type);
>> +#else
>> +#define erofs_get_acl (NULL)
>> +#endif
>> +
>> #endif
>>
>>
>
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