2023-06-08 11:44:16

by Jingbo Xu

[permalink] [raw]
Subject: [PATCH v6 0/5] erofs: cleanup of xattr handling

changes since v5:
- patch 1: newly added into this series, in preparation for the
following cleanup
- patch 5: rename erofs_xattr_body() to erofs_xattr_handle_string()

changes since v4:
- patch 1: make conversions from erofs_read_metabuf() in xattr.c
to "erofs_init_metabuf() + erofs_bread()" a separate patch
- patch 6: add "bool copy" function parameter to erofs_xattr_body(), and
thus make erofs_xattr_namematch() and erofs_xattr_copy() inlined
inside erofs_xattr_body()

changes since v3:
- patch 1: make a unified erofs_xattr_iter_fixup() API with newly
introduced "bool nospan" argument; call erofs_init_metabuf() and
erofs_bread() separately instead of erofs_read_metabuf()
- patch 2: avoid duplicated strlen() calculation in erofs_getxattr(); no
need zeroing other fields when initializing 'struct erofs_xattr_iter'
- patch 4: don't explode 'struct erofs_xattr_iter' with inode/getxattr
fields; instead pass inode/getxattr parameters through function
parameters of erofs_iter_[inline|shared]_xattr()
- patch 5: don't explode 'struct erofs_xattr_iter' with remaining field;
instead calculate and check the remaining inside
erofs_iter_inline_xattr()

changes since v2:
- rebase to v6.4-rc2
- passes xattr tests (erofs/019,020,021) of erofs-utils [1]

[1] https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs-utils.git/log/?h=experimental-tests

v5: https://lore.kernel.org/all/[email protected]/
v4: https://lore.kernel.org/all/[email protected]/
v3: https://lore.kernel.org/lkml/[email protected]/
v2: https://lore.kernel.org/all/[email protected]/
v1: https://lore.kernel.org/all/[email protected]/


Jingbo Xu (5):
erofs: use absolute position in xattr iterator
erofs: unify xattr_iter structures
erofs: make the size of read data stored in buffer_ofs
erofs: unify inline/share xattr iterators for listxattr/getxattr
erofs: use separate xattr parsers for listxattr/getxattr

fs/erofs/xattr.c | 652 +++++++++++++++++------------------------------
1 file changed, 227 insertions(+), 425 deletions(-)

--
2.19.1.6.gb485710b



2023-06-08 11:57:52

by Jingbo Xu

[permalink] [raw]
Subject: [PATCH v6 4/5] erofs: unify inline/share xattr iterators for listxattr/getxattr

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 <[email protected]>
---
fs/erofs/xattr.c | 188 ++++++++++++++++++-----------------------------
1 file changed, 73 insertions(+), 115 deletions(-)

diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
index 4ae9b7cdd3ac..15a1a4042205 100644
--- a/fs/erofs/xattr.c
+++ b/fs/erofs/xattr.c
@@ -139,27 +139,6 @@ 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;
-
- 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;
- }
-
- it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
- it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos),
- 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
* `pos' pointing to the next xattr item rather than an arbitrary position.
@@ -333,47 +312,6 @@ 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->pos = erofs_pos(sb, EROFS_SB(sb)->xattr_blkaddr) +
- xsid * sizeof(__u32);
- it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos),
- 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);
@@ -384,39 +322,6 @@ 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)
@@ -521,31 +426,48 @@ 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;
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;
+ }
+
+ it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
+ it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos),
+ 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];
@@ -556,11 +478,44 @@ static int shared_listxattr(struct erofs_xattr_iter *it)
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,
@@ -568,8 +523,9 @@ 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)
@@ -583,11 +539,13 @@ 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)
--
2.19.1.6.gb485710b


2023-06-12 03:06:47

by Gao Xiang

[permalink] [raw]
Subject: Re: [PATCH v6 4/5] erofs: unify inline/share xattr iterators for listxattr/getxattr



On 2023/6/8 19:30, Jingbo Xu wrote:
> Make inline_getxattr() and inline_listxattr() unified as
> iter_inline_xattr(), shared_getxattr() and shared_listxattr() unified as

erofs_xattr_iter_inline() as well as shared_getxattr() and
shared_listxattr() unified as erofs_xattr_iter_shared() ?

> iter_shared_xattr().
>
> After the unification, both iter_inline_xattr() and iter_shared_xattr()
> return 0 on success, and negative error on failure.

After these changes, both erofs_xattr_iter_{inline,shared} return 0 on
success, and negative values 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 <[email protected]>

Otherwise it looks good to me.

Thanks,
Gao Xiang

> ---
> fs/erofs/xattr.c | 188 ++++++++++++++++++-----------------------------
> 1 file changed, 73 insertions(+), 115 deletions(-)
>
> diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
> index 4ae9b7cdd3ac..15a1a4042205 100644
> --- a/fs/erofs/xattr.c
> +++ b/fs/erofs/xattr.c
> @@ -139,27 +139,6 @@ 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;
> -
> - 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;
> - }
> -
> - it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
> - it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos),
> - 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
> * `pos' pointing to the next xattr item rather than an arbitrary position.
> @@ -333,47 +312,6 @@ 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->pos = erofs_pos(sb, EROFS_SB(sb)->xattr_blkaddr) +
> - xsid * sizeof(__u32);
> - it->kaddr = erofs_bread(&it->buf, erofs_blknr(sb, it->pos),
> - 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);
> @@ -384,39 +322,6 @@ 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)
> @@ -521,31 +426,48 @@ 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;
> 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;
> + }
> +
> + it->pos = erofs_iloc(inode) + vi->inode_isize + xattr_header_sz;
> + it->kaddr = erofs_bread(&it->buf, erofs_blknr(it->sb, it->pos),
> + 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];
> @@ -556,11 +478,44 @@ static int shared_listxattr(struct erofs_xattr_iter *it)
> 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,
> @@ -568,8 +523,9 @@ 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)
> @@ -583,11 +539,13 @@ 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)