[v4,4/5] erofs: unify inline/share xattr iterators for listxattr/getxattr
Commit Message
Make inline_getxattr() and inline_listxattr() unified as
iter_inline_xattr(), shared_getxattr() and shared_listxattr() unified as
iter_shared_xattr().
After the unification, both iter_inline_xattr() and iter_shared_xattr()
return 0 on success, and negative error on failure.
One thing worth noting is that, the logic of returning it->buffer_ofs
when there's no shared xattrs in shared_listxattr() is moved to
erofs_listxattr() to make the unification possible. The only difference
is that, semantically the old behavior will return ENOATTR rather than
it->buffer_ofs if ENOATTR encountered when listxattr is parsing upon a
specific shared xattr, while now the new behavior will return
it->buffer_ofs in this case. This is not an issue, as listxattr upon a
specific xattr won't return ENOATTR.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
---
fs/erofs/xattr.c | 210 ++++++++++++++++++-----------------------------
1 file changed, 78 insertions(+), 132 deletions(-)
Comments
On 2023/5/31 11:13, Jingbo Xu wrote:
> Make inline_getxattr() and inline_listxattr() unified as
> iter_inline_xattr(), shared_getxattr() and shared_listxattr() unified as
> iter_shared_xattr().
>
> After the unification, both iter_inline_xattr() and iter_shared_xattr()
> return 0 on success, and negative error on failure.
>
> One thing worth noting is that, the logic of returning it->buffer_ofs
> when there's no shared xattrs in shared_listxattr() is moved to
> erofs_listxattr() to make the unification possible. The only difference
> is that, semantically the old behavior will return ENOATTR rather than
> it->buffer_ofs if ENOATTR encountered when listxattr is parsing upon a
> specific shared xattr, while now the new behavior will return
> it->buffer_ofs in this case. This is not an issue, as listxattr upon a
> specific xattr won't return ENOATTR.
>
> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
> ---
> fs/erofs/xattr.c | 210 ++++++++++++++++++-----------------------------
> 1 file changed, 78 insertions(+), 132 deletions(-)
>
> diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
> index 7c76b4d31920..074743e2b271 100644
> --- a/fs/erofs/xattr.c
> +++ b/fs/erofs/xattr.c
> @@ -7,19 +7,6 @@
> #include <linux/security.h>
> #include "xattr.h"
>
> -static inline erofs_blk_t erofs_xattr_blkaddr(struct super_block *sb,
> - unsigned int xattr_id)
> -{
> - return EROFS_SB(sb)->xattr_blkaddr +
> - erofs_blknr(sb, xattr_id * sizeof(__u32));
> -}
> -
> -static inline unsigned int erofs_xattr_blkoff(struct super_block *sb,
> - unsigned int xattr_id)
> -{
> - return erofs_blkoff(sb, xattr_id * sizeof(__u32));
> -}
> -
> struct erofs_xattr_iter {
> struct super_block *sb;
> struct erofs_buf buf;
> @@ -170,30 +157,6 @@ struct xattr_iter_handlers {
> unsigned int len);
> };
>
> -static int inline_xattr_iter_begin(struct erofs_xattr_iter *it,
> - struct inode *inode)
> -{
> - struct erofs_inode *const vi = EROFS_I(inode);
> - unsigned int xattr_header_sz, inline_xattr_ofs;
> -
> - xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
> - sizeof(u32) * vi->xattr_shared_count;
> - if (xattr_header_sz >= vi->xattr_isize) {
> - DBG_BUGON(xattr_header_sz > vi->xattr_isize);
> - return -ENOATTR;
> - }
> -
> - inline_xattr_ofs = vi->inode_isize + xattr_header_sz;
> -
> - it->blkaddr = erofs_blknr(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
> - it->ofs = erofs_blkoff(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
> - it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr,
> - EROFS_KMAP);
> - if (IS_ERR(it->kaddr))
> - return PTR_ERR(it->kaddr);
> - return vi->xattr_isize - xattr_header_sz;
> -}
> -
> /*
> * Regardless of success or failure, `xattr_foreach' will end up with
> * `ofs' pointing to the next xattr item rather than an arbitrary position.
> @@ -355,46 +318,6 @@ static const struct xattr_iter_handlers find_xattr_handlers = {
> .value = xattr_copyvalue
> };
>
> -static int inline_getxattr(struct inode *inode, struct erofs_xattr_iter *it)
> -{
> - int ret;
> - unsigned int remaining;
> -
> - ret = inline_xattr_iter_begin(it, inode);
> - if (ret < 0)
> - return ret;
> -
> - remaining = ret;
> - while (remaining) {
> - ret = xattr_foreach(it, &find_xattr_handlers, &remaining);
> - if (ret != -ENOATTR)
> - break;
> - }
> - return ret ? ret : it->buffer_ofs;
> -}
> -
> -static int shared_getxattr(struct inode *inode, struct erofs_xattr_iter *it)
> -{
> - struct erofs_inode *const vi = EROFS_I(inode);
> - struct super_block *const sb = it->sb;
> - unsigned int i, xsid;
> - int ret = -ENOATTR;
> -
> - for (i = 0; i < vi->xattr_shared_count; ++i) {
> - xsid = vi->xattr_shared_xattrs[i];
> - it->blkaddr = erofs_xattr_blkaddr(sb, xsid);
> - it->ofs = erofs_xattr_blkoff(sb, xsid);
> - it->kaddr = erofs_read_metabuf(&it->buf, sb, it->blkaddr, EROFS_KMAP);
> - if (IS_ERR(it->kaddr))
> - return PTR_ERR(it->kaddr);
> -
> - ret = xattr_foreach(it, &find_xattr_handlers, NULL);
> - if (ret != -ENOATTR)
> - break;
> - }
> - return ret ? ret : it->buffer_ofs;
> -}
> -
> static bool erofs_xattr_user_list(struct dentry *dentry)
> {
> return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER);
> @@ -405,39 +328,6 @@ static bool erofs_xattr_trusted_list(struct dentry *dentry)
> return capable(CAP_SYS_ADMIN);
> }
>
> -int erofs_getxattr(struct inode *inode, int index,
> - const char *name,
> - void *buffer, size_t buffer_size)
> -{
> - int ret;
> - struct erofs_xattr_iter it;
> -
> - if (!name)
> - return -EINVAL;
> -
> - ret = erofs_init_inode_xattrs(inode);
> - if (ret)
> - return ret;
> -
> - it.index = index;
> - it.name = (struct qstr)QSTR_INIT(name, strlen(name));
> - if (it.name.len > EROFS_NAME_LEN)
> - return -ERANGE;
> -
> - it.sb = inode->i_sb;
> - it.buf = __EROFS_BUF_INITIALIZER;
> - erofs_init_metabuf(&it.buf, it.sb);
> - it.buffer = buffer;
> - it.buffer_size = buffer_size;
> - it.buffer_ofs = 0;
> -
> - ret = inline_getxattr(inode, &it);
> - if (ret == -ENOATTR)
> - ret = shared_getxattr(inode, &it);
> - erofs_put_metabuf(&it.buf);
> - return ret;
> -}
> -
> static int erofs_xattr_generic_get(const struct xattr_handler *handler,
> struct dentry *unused, struct inode *inode,
> const char *name, void *buffer, size_t size)
> @@ -542,45 +432,98 @@ static const struct xattr_iter_handlers list_xattr_handlers = {
> .value = NULL
> };
>
> -static int inline_listxattr(struct erofs_xattr_iter *it)
> +static int erofs_iter_inline_xattr(struct erofs_xattr_iter *it,
> + struct inode *inode, bool getxattr)
> {
> + struct erofs_inode *const vi = EROFS_I(inode);
> + const struct xattr_iter_handlers *op;
> + unsigned int xattr_header_sz, remaining;
> + erofs_off_t pos;
> int ret;
> - unsigned int remaining;
>
> - ret = inline_xattr_iter_begin(it, d_inode(it->dentry));
In the past, "ret" here is "an int", and
vi->xattr_isize - xattr_header_sz < 0 will return
negative value (although I think that value is problematic).
see below.
> - if (ret < 0)
> - return ret;
> + xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
> + sizeof(u32) * vi->xattr_shared_count;
> + if (xattr_header_sz >= vi->xattr_isize) {
> + DBG_BUGON(xattr_header_sz > vi->xattr_isize);
> + return -ENOATTR;
> + }
> +
> + pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
> + it->blkaddr = erofs_blknr(it->sb, pos);
> + it->ofs = erofs_blkoff(it->sb, pos);
> + it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr, EROFS_KMAP);
> + if (IS_ERR(it->kaddr))
> + return PTR_ERR(it->kaddr);
> +
> + remaining = vi->xattr_isize - xattr_header_sz;
so in this patch, `vi->xattr_isize - xattr_header_sz` here could be
negative that should be avoided as well.
Thanks,
Gao Xiang
On 5/31/23 2:57 PM, Gao Xiang wrote:
>
>
> On 2023/5/31 11:13, Jingbo Xu wrote:
>> -static int inline_xattr_iter_begin(struct erofs_xattr_iter *it,
>> - struct inode *inode)
>> -{
>> - struct erofs_inode *const vi = EROFS_I(inode);
>> - unsigned int xattr_header_sz, inline_xattr_ofs;
>> -
>> - xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
>> - sizeof(u32) * vi->xattr_shared_count;
>> - if (xattr_header_sz >= vi->xattr_isize) {
>> - DBG_BUGON(xattr_header_sz > vi->xattr_isize);
>> - return -ENOATTR;
>> - }
In the original implementation, here when xattr_header_sz >=
vi->xattr_isize, inline_xattr_iter_begin() will return -ENOATTR rather
than a negative integer (i.e. vi->xattr_isize - xattr_header_sz).
>> static int erofs_xattr_generic_get(const struct xattr_handler *handler,
>> struct dentry *unused, struct inode *inode,
>> const char *name, void *buffer, size_t size)
>> @@ -542,45 +432,98 @@ static const struct xattr_iter_handlers
>> list_xattr_handlers = {
>> .value = NULL
>> };
>> -static int inline_listxattr(struct erofs_xattr_iter *it)
>> +static int erofs_iter_inline_xattr(struct erofs_xattr_iter *it,
>> + struct inode *inode, bool getxattr)
>> {
>> + struct erofs_inode *const vi = EROFS_I(inode);
>> + const struct xattr_iter_handlers *op;
>> + unsigned int xattr_header_sz, remaining;
>> + erofs_off_t pos;
>> int ret;
>> - unsigned int remaining;
>> - ret = inline_xattr_iter_begin(it, d_inode(it->dentry));
>
> In the past, "ret" here is "an int", and
> vi->xattr_isize - xattr_header_sz < 0 will return
> negative value (although I think that value is problematic).
>
> see below.
See comment above.
>
>
>> - if (ret < 0)
>> - return ret;
>> + xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
>> + sizeof(u32) * vi->xattr_shared_count;
>> + if (xattr_header_sz >= vi->xattr_isize) {
>> + DBG_BUGON(xattr_header_sz > vi->xattr_isize);
>> + return -ENOATTR;
>> + }
This checking for "xattr_header_sz >= vi->xattr_isize" is also included
in this patch.
On 2023/5/31 16:16, Jingbo Xu wrote:
>
>
> On 5/31/23 2:57 PM, Gao Xiang wrote:
>>
>>
>> On 2023/5/31 11:13, Jingbo Xu wrote:
>>> -static int inline_xattr_iter_begin(struct erofs_xattr_iter *it,
>>> - struct inode *inode)
>>> -{
>>> - struct erofs_inode *const vi = EROFS_I(inode);
>>> - unsigned int xattr_header_sz, inline_xattr_ofs;
>>> -
>>> - xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
>>> - sizeof(u32) * vi->xattr_shared_count;
>>> - if (xattr_header_sz >= vi->xattr_isize) {
>>> - DBG_BUGON(xattr_header_sz > vi->xattr_isize);
>>> - return -ENOATTR;
>>> - }
>
> In the original implementation, here when xattr_header_sz >=
> vi->xattr_isize, inline_xattr_iter_begin() will return -ENOATTR rather
> than a negative integer (i.e. vi->xattr_isize - xattr_header_sz).
Ah, sorry I misreaded that.
Thanks,
Gao Xiang
@@ -7,19 +7,6 @@
#include <linux/security.h>
#include "xattr.h"
-static inline erofs_blk_t erofs_xattr_blkaddr(struct super_block *sb,
- unsigned int xattr_id)
-{
- return EROFS_SB(sb)->xattr_blkaddr +
- erofs_blknr(sb, xattr_id * sizeof(__u32));
-}
-
-static inline unsigned int erofs_xattr_blkoff(struct super_block *sb,
- unsigned int xattr_id)
-{
- return erofs_blkoff(sb, xattr_id * sizeof(__u32));
-}
-
struct erofs_xattr_iter {
struct super_block *sb;
struct erofs_buf buf;
@@ -170,30 +157,6 @@ struct xattr_iter_handlers {
unsigned int len);
};
-static int inline_xattr_iter_begin(struct erofs_xattr_iter *it,
- struct inode *inode)
-{
- struct erofs_inode *const vi = EROFS_I(inode);
- unsigned int xattr_header_sz, inline_xattr_ofs;
-
- xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
- sizeof(u32) * vi->xattr_shared_count;
- if (xattr_header_sz >= vi->xattr_isize) {
- DBG_BUGON(xattr_header_sz > vi->xattr_isize);
- return -ENOATTR;
- }
-
- inline_xattr_ofs = vi->inode_isize + xattr_header_sz;
-
- it->blkaddr = erofs_blknr(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
- it->ofs = erofs_blkoff(it->sb, erofs_iloc(inode) + inline_xattr_ofs);
- it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr,
- EROFS_KMAP);
- if (IS_ERR(it->kaddr))
- return PTR_ERR(it->kaddr);
- return vi->xattr_isize - xattr_header_sz;
-}
-
/*
* Regardless of success or failure, `xattr_foreach' will end up with
* `ofs' pointing to the next xattr item rather than an arbitrary position.
@@ -355,46 +318,6 @@ static const struct xattr_iter_handlers find_xattr_handlers = {
.value = xattr_copyvalue
};
-static int inline_getxattr(struct inode *inode, struct erofs_xattr_iter *it)
-{
- int ret;
- unsigned int remaining;
-
- ret = inline_xattr_iter_begin(it, inode);
- if (ret < 0)
- return ret;
-
- remaining = ret;
- while (remaining) {
- ret = xattr_foreach(it, &find_xattr_handlers, &remaining);
- if (ret != -ENOATTR)
- break;
- }
- return ret ? ret : it->buffer_ofs;
-}
-
-static int shared_getxattr(struct inode *inode, struct erofs_xattr_iter *it)
-{
- struct erofs_inode *const vi = EROFS_I(inode);
- struct super_block *const sb = it->sb;
- unsigned int i, xsid;
- int ret = -ENOATTR;
-
- for (i = 0; i < vi->xattr_shared_count; ++i) {
- xsid = vi->xattr_shared_xattrs[i];
- it->blkaddr = erofs_xattr_blkaddr(sb, xsid);
- it->ofs = erofs_xattr_blkoff(sb, xsid);
- it->kaddr = erofs_read_metabuf(&it->buf, sb, it->blkaddr, EROFS_KMAP);
- if (IS_ERR(it->kaddr))
- return PTR_ERR(it->kaddr);
-
- ret = xattr_foreach(it, &find_xattr_handlers, NULL);
- if (ret != -ENOATTR)
- break;
- }
- return ret ? ret : it->buffer_ofs;
-}
-
static bool erofs_xattr_user_list(struct dentry *dentry)
{
return test_opt(&EROFS_SB(dentry->d_sb)->opt, XATTR_USER);
@@ -405,39 +328,6 @@ static bool erofs_xattr_trusted_list(struct dentry *dentry)
return capable(CAP_SYS_ADMIN);
}
-int erofs_getxattr(struct inode *inode, int index,
- const char *name,
- void *buffer, size_t buffer_size)
-{
- int ret;
- struct erofs_xattr_iter it;
-
- if (!name)
- return -EINVAL;
-
- ret = erofs_init_inode_xattrs(inode);
- if (ret)
- return ret;
-
- it.index = index;
- it.name = (struct qstr)QSTR_INIT(name, strlen(name));
- if (it.name.len > EROFS_NAME_LEN)
- return -ERANGE;
-
- it.sb = inode->i_sb;
- it.buf = __EROFS_BUF_INITIALIZER;
- erofs_init_metabuf(&it.buf, it.sb);
- it.buffer = buffer;
- it.buffer_size = buffer_size;
- it.buffer_ofs = 0;
-
- ret = inline_getxattr(inode, &it);
- if (ret == -ENOATTR)
- ret = shared_getxattr(inode, &it);
- erofs_put_metabuf(&it.buf);
- return ret;
-}
-
static int erofs_xattr_generic_get(const struct xattr_handler *handler,
struct dentry *unused, struct inode *inode,
const char *name, void *buffer, size_t size)
@@ -542,45 +432,98 @@ static const struct xattr_iter_handlers list_xattr_handlers = {
.value = NULL
};
-static int inline_listxattr(struct erofs_xattr_iter *it)
+static int erofs_iter_inline_xattr(struct erofs_xattr_iter *it,
+ struct inode *inode, bool getxattr)
{
+ struct erofs_inode *const vi = EROFS_I(inode);
+ const struct xattr_iter_handlers *op;
+ unsigned int xattr_header_sz, remaining;
+ erofs_off_t pos;
int ret;
- unsigned int remaining;
- ret = inline_xattr_iter_begin(it, d_inode(it->dentry));
- if (ret < 0)
- return ret;
+ xattr_header_sz = sizeof(struct erofs_xattr_ibody_header) +
+ sizeof(u32) * vi->xattr_shared_count;
+ if (xattr_header_sz >= vi->xattr_isize) {
+ DBG_BUGON(xattr_header_sz > vi->xattr_isize);
+ return -ENOATTR;
+ }
+
+ pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
+ it->blkaddr = erofs_blknr(it->sb, pos);
+ it->ofs = erofs_blkoff(it->sb, pos);
+ it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr, EROFS_KMAP);
+ if (IS_ERR(it->kaddr))
+ return PTR_ERR(it->kaddr);
+
+ remaining = vi->xattr_isize - xattr_header_sz;
+ op = getxattr ? &find_xattr_handlers : &list_xattr_handlers;
- remaining = ret;
while (remaining) {
- ret = xattr_foreach(it, &list_xattr_handlers, &remaining);
- if (ret)
+ ret = xattr_foreach(it, op, &remaining);
+ if ((getxattr && ret != -ENOATTR) || (!getxattr && ret))
break;
}
- return ret ? ret : it->buffer_ofs;
+ return ret;
}
-static int shared_listxattr(struct erofs_xattr_iter *it)
+static int erofs_iter_shared_xattr(struct erofs_xattr_iter *it,
+ struct inode *inode, bool getxattr)
{
- struct inode *const inode = d_inode(it->dentry);
struct erofs_inode *const vi = EROFS_I(inode);
struct super_block *const sb = it->sb;
+ const struct xattr_iter_handlers *op;
unsigned int i, xsid;
- int ret = 0;
+ int ret = -ENOATTR;
+
+ op = getxattr ? &find_xattr_handlers : &list_xattr_handlers;
for (i = 0; i < vi->xattr_shared_count; ++i) {
xsid = vi->xattr_shared_xattrs[i];
- it->blkaddr = erofs_xattr_blkaddr(sb, xsid);
- it->ofs = erofs_xattr_blkoff(sb, xsid);
+ it->blkaddr = EROFS_SB(sb)->xattr_blkaddr +
+ erofs_blknr(sb, xsid * sizeof(__u32));
+ it->ofs = erofs_blkoff(sb, xsid * sizeof(__u32));
it->kaddr = erofs_read_metabuf(&it->buf, sb, it->blkaddr, EROFS_KMAP);
if (IS_ERR(it->kaddr))
return PTR_ERR(it->kaddr);
- ret = xattr_foreach(it, &list_xattr_handlers, NULL);
- if (ret)
+ ret = xattr_foreach(it, op, NULL);
+ if ((getxattr && ret != -ENOATTR) || (!getxattr && ret))
break;
}
- return ret ? ret : it->buffer_ofs;
+ return ret;
+}
+
+int erofs_getxattr(struct inode *inode, int index,
+ const char *name,
+ void *buffer, size_t buffer_size)
+{
+ int ret;
+ struct erofs_xattr_iter it;
+
+ if (!name)
+ return -EINVAL;
+
+ ret = erofs_init_inode_xattrs(inode);
+ if (ret)
+ return ret;
+
+ it.index = index;
+ it.name = (struct qstr)QSTR_INIT(name, strlen(name));
+ if (it.name.len > EROFS_NAME_LEN)
+ return -ERANGE;
+
+ it.sb = inode->i_sb;
+ it.buf = __EROFS_BUF_INITIALIZER;
+ erofs_init_metabuf(&it.buf, it.sb);
+ it.buffer = buffer;
+ it.buffer_size = buffer_size;
+ it.buffer_ofs = 0;
+
+ ret = erofs_iter_inline_xattr(&it, inode, true);
+ if (ret == -ENOATTR)
+ ret = erofs_iter_shared_xattr(&it, inode, true);
+ erofs_put_metabuf(&it.buf);
+ return ret ? ret : it.buffer_ofs;
}
ssize_t erofs_listxattr(struct dentry *dentry,
@@ -588,8 +531,9 @@ ssize_t erofs_listxattr(struct dentry *dentry,
{
int ret;
struct erofs_xattr_iter it;
+ struct inode *inode = d_inode(dentry);
- ret = erofs_init_inode_xattrs(d_inode(dentry));
+ ret = erofs_init_inode_xattrs(inode);
if (ret == -ENOATTR)
return 0;
if (ret)
@@ -603,11 +547,13 @@ ssize_t erofs_listxattr(struct dentry *dentry,
it.buffer_size = buffer_size;
it.buffer_ofs = 0;
- ret = inline_listxattr(&it);
- if (ret >= 0 || ret == -ENOATTR)
- ret = shared_listxattr(&it);
+ ret = erofs_iter_inline_xattr(&it, inode, false);
+ if (!ret || ret == -ENOATTR)
+ ret = erofs_iter_shared_xattr(&it, inode, false);
+ if (ret == -ENOATTR)
+ ret = 0;
erofs_put_metabuf(&it.buf);
- return ret;
+ return ret ? ret : it.buffer_ofs;
}
void erofs_xattr_prefixes_cleanup(struct super_block *sb)