From: "Darrick J. Wong" <djwong@kernel.org>
To: allison.henderson@oracle.com
Cc: linux-xfs@vger.kernel.org
Subject: Re: [PATCH v3 01/26] xfs: Add new name to attri/d
Date: Fri, 23 Sep 2022 11:53:24 -0700 [thread overview]
Message-ID: <Yy4ApOh1RuUbC8gW@magnolia> (raw)
In-Reply-To: <20220922054458.40826-2-allison.henderson@oracle.com>
On Wed, Sep 21, 2022 at 10:44:33PM -0700, allison.henderson@oracle.com wrote:
> From: Allison Henderson <allison.henderson@oracle.com>
>
> This patch adds two new fields to the atti/d. They are nname and
> nnamelen. This will be used for parent pointer updates since a
> rename operation may cause the parent pointer to update both the
> name and value. So we need to carry both the new name as well as
> the target name in the attri/d.
>
> Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
> ---
> fs/xfs/libxfs/xfs_attr.c | 12 +++-
> fs/xfs/libxfs/xfs_attr.h | 4 +-
> fs/xfs/libxfs/xfs_da_btree.h | 2 +
> fs/xfs/libxfs/xfs_log_format.h | 6 +-
> fs/xfs/xfs_attr_item.c | 108 ++++++++++++++++++++++++++++-----
> fs/xfs/xfs_attr_item.h | 1 +
> 6 files changed, 113 insertions(+), 20 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index e28d93d232de..b1dbed7655e8 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -423,6 +423,12 @@ xfs_attr_complete_op(
> args->op_flags &= ~XFS_DA_OP_REPLACE;
> if (do_replace) {
> args->attr_filter &= ~XFS_ATTR_INCOMPLETE;
> + if (args->new_namelen > 0) {
> + args->name = args->new_name;
> + args->namelen = args->new_namelen;
/me wonders, do we need to null out new_name and new_namelen here?
I /think/ the answer is that the current codebase doesn't care since
we're now doing XFS_DA_OP_ADDNAME, and addname looks only at
name/namelen and has no idea that new_name/new_namelen even exist?
> + args->hashval = xfs_da_hashname(args->name,
> + args->namelen);
> + }
> return replace_state;
> }
> return XFS_DAS_DONE;
> @@ -922,9 +928,13 @@ xfs_attr_defer_replace(
> struct xfs_da_args *args)
> {
> struct xfs_attr_intent *new;
> + int op_flag;
> int error = 0;
>
> - error = xfs_attr_intent_init(args, XFS_ATTRI_OP_FLAGS_REPLACE, &new);
> + op_flag = args->new_namelen == 0 ? XFS_ATTRI_OP_FLAGS_REPLACE :
> + XFS_ATTRI_OP_FLAGS_NVREPLACE;
> +
> + error = xfs_attr_intent_init(args, op_flag, &new);
> if (error)
> return error;
>
> diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
> index 81be9b3e4004..3e81f3f48560 100644
> --- a/fs/xfs/libxfs/xfs_attr.h
> +++ b/fs/xfs/libxfs/xfs_attr.h
> @@ -510,8 +510,8 @@ struct xfs_attr_intent {
> struct xfs_da_args *xattri_da_args;
>
> /*
> - * Shared buffer containing the attr name and value so that the logging
> - * code can share large memory buffers between log items.
> + * Shared buffer containing the attr name, new name, and value so that
> + * the logging code can share large memory buffers between log items.
> */
> struct xfs_attri_log_nameval *xattri_nameval;
>
> diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h
> index ffa3df5b2893..a4b29827603f 100644
> --- a/fs/xfs/libxfs/xfs_da_btree.h
> +++ b/fs/xfs/libxfs/xfs_da_btree.h
> @@ -55,7 +55,9 @@ enum xfs_dacmp {
> typedef struct xfs_da_args {
> struct xfs_da_geometry *geo; /* da block geometry */
> const uint8_t *name; /* string (maybe not NULL terminated) */
> + const uint8_t *new_name; /* new attr name */
> int namelen; /* length of string (maybe no NULL) */
> + int new_namelen; /* new attr name len */
> uint8_t filetype; /* filetype of inode for directories */
> void *value; /* set of bytes (maybe contain NULLs) */
> int valuelen; /* length of value */
/me starts to wonder if the two name len fields and the value len field
ought to be u8/u16 to conserve space in xfs_da_args, but that's an
optimization question for after this patchset.
> diff --git a/fs/xfs/libxfs/xfs_log_format.h b/fs/xfs/libxfs/xfs_log_format.h
> index b351b9dc6561..62f40e6353c2 100644
> --- a/fs/xfs/libxfs/xfs_log_format.h
> +++ b/fs/xfs/libxfs/xfs_log_format.h
> @@ -117,7 +117,8 @@ struct xfs_unmount_log_format {
> #define XLOG_REG_TYPE_ATTRD_FORMAT 28
> #define XLOG_REG_TYPE_ATTR_NAME 29
> #define XLOG_REG_TYPE_ATTR_VALUE 30
> -#define XLOG_REG_TYPE_MAX 30
> +#define XLOG_REG_TYPE_ATTR_NNAME 31
> +#define XLOG_REG_TYPE_MAX 31
>
>
> /*
> @@ -909,6 +910,7 @@ struct xfs_icreate_log {
> #define XFS_ATTRI_OP_FLAGS_SET 1 /* Set the attribute */
> #define XFS_ATTRI_OP_FLAGS_REMOVE 2 /* Remove the attribute */
> #define XFS_ATTRI_OP_FLAGS_REPLACE 3 /* Replace the attribute */
> +#define XFS_ATTRI_OP_FLAGS_NVREPLACE 4 /* Replace attr name and val */
> #define XFS_ATTRI_OP_FLAGS_TYPE_MASK 0xFF /* Flags type mask */
>
> /*
> @@ -926,7 +928,7 @@ struct xfs_icreate_log {
> struct xfs_attri_log_format {
> uint16_t alfi_type; /* attri log item type */
> uint16_t alfi_size; /* size of this item */
> - uint32_t __pad; /* pad to 64 bit aligned */
> + uint32_t alfi_nname_len; /* attr new name length */
> uint64_t alfi_id; /* attri identifier */
> uint64_t alfi_ino; /* the inode for this attr operation */
> uint32_t alfi_op_flags; /* marks the op as a set or remove */
> diff --git a/fs/xfs/xfs_attr_item.c b/fs/xfs/xfs_attr_item.c
> index cf5ce607dc05..9414ee94829c 100644
> --- a/fs/xfs/xfs_attr_item.c
> +++ b/fs/xfs/xfs_attr_item.c
> @@ -75,6 +75,8 @@ static inline struct xfs_attri_log_nameval *
> xfs_attri_log_nameval_alloc(
> const void *name,
> unsigned int name_len,
> + const void *nname,
> + unsigned int nname_len,
> const void *value,
> unsigned int value_len)
> {
> @@ -85,15 +87,25 @@ xfs_attri_log_nameval_alloc(
> * this. But kvmalloc() utterly sucks, so we use our own version.
> */
> nv = xlog_kvmalloc(sizeof(struct xfs_attri_log_nameval) +
> - name_len + value_len);
> + name_len + nname_len + value_len);
>
> nv->name.i_addr = nv + 1;
> nv->name.i_len = name_len;
> nv->name.i_type = XLOG_REG_TYPE_ATTR_NAME;
> memcpy(nv->name.i_addr, name, name_len);
>
> + if (nname_len) {
> + nv->nname.i_addr = nv->name.i_addr + name_len;
> + nv->nname.i_len = nname_len;
> + memcpy(nv->nname.i_addr, nname, nname_len);
> + } else {
> + nv->nname.i_addr = NULL;
> + nv->nname.i_len = 0;
> + }
> + nv->nname.i_type = XLOG_REG_TYPE_ATTR_NNAME;
> +
> if (value_len) {
> - nv->value.i_addr = nv->name.i_addr + name_len;
> + nv->value.i_addr = nv->name.i_addr + nname_len + name_len;
> nv->value.i_len = value_len;
> memcpy(nv->value.i_addr, value, value_len);
> } else {
> @@ -147,11 +159,15 @@ xfs_attri_item_size(
> *nbytes += sizeof(struct xfs_attri_log_format) +
> xlog_calc_iovec_len(nv->name.i_len);
>
> - if (!nv->value.i_len)
> - return;
> + if (nv->nname.i_len) {
> + *nvecs += 1;
> + *nbytes += xlog_calc_iovec_len(nv->nname.i_len);
> + }
>
> - *nvecs += 1;
> - *nbytes += xlog_calc_iovec_len(nv->value.i_len);
> + if (nv->value.i_len) {
> + *nvecs += 1;
> + *nbytes += xlog_calc_iovec_len(nv->value.i_len);
> + }
> }
>
> /*
> @@ -181,6 +197,9 @@ xfs_attri_item_format(
> ASSERT(nv->name.i_len > 0);
> attrip->attri_format.alfi_size++;
>
> + if (nv->nname.i_len > 0)
> + attrip->attri_format.alfi_size++;
> +
> if (nv->value.i_len > 0)
> attrip->attri_format.alfi_size++;
>
> @@ -188,6 +207,10 @@ xfs_attri_item_format(
> &attrip->attri_format,
> sizeof(struct xfs_attri_log_format));
> xlog_copy_from_iovec(lv, &vecp, &nv->name);
> +
> + if (nv->nname.i_len > 0)
> + xlog_copy_from_iovec(lv, &vecp, &nv->nname);
> +
> if (nv->value.i_len > 0)
> xlog_copy_from_iovec(lv, &vecp, &nv->value);
> }
> @@ -396,6 +419,7 @@ xfs_attr_log_item(
> attrp->alfi_op_flags = attr->xattri_op_flags;
> attrp->alfi_value_len = attr->xattri_nameval->value.i_len;
> attrp->alfi_name_len = attr->xattri_nameval->name.i_len;
> + attrp->alfi_nname_len = attr->xattri_nameval->nname.i_len;
> ASSERT(!(attr->xattri_da_args->attr_filter & ~XFS_ATTRI_FILTER_MASK));
> attrp->alfi_attr_filter = attr->xattri_da_args->attr_filter;
> }
> @@ -437,7 +461,8 @@ xfs_attr_create_intent(
> * deferred work state structure.
> */
> attr->xattri_nameval = xfs_attri_log_nameval_alloc(args->name,
> - args->namelen, args->value, args->valuelen);
> + args->namelen, args->new_name,
> + args->new_namelen, args->value, args->valuelen);
> }
>
> attrip = xfs_attri_init(mp, attr->xattri_nameval);
> @@ -525,9 +550,6 @@ xfs_attri_validate(
> unsigned int op = attrp->alfi_op_flags &
> XFS_ATTRI_OP_FLAGS_TYPE_MASK;
>
> - if (attrp->__pad != 0)
> - return false;
I don't think it's correct to remove this check entirely -- NVREPLACE is
the only operation that uses nname/nname_len, right? Shouldn't this be:
if (op_flags != XFS_ATTRI_OP_FLAGS_NVREPLACE &&
attrp->alfi_nname_len != 0)
return false;
> -
> if (attrp->alfi_op_flags & ~XFS_ATTRI_OP_FLAGS_TYPE_MASK)
> return false;
>
> @@ -539,6 +561,7 @@ xfs_attri_validate(
> case XFS_ATTRI_OP_FLAGS_SET:
> case XFS_ATTRI_OP_FLAGS_REPLACE:
> case XFS_ATTRI_OP_FLAGS_REMOVE:
> + case XFS_ATTRI_OP_FLAGS_NVREPLACE:
> break;
> default:
> return false;
> @@ -548,9 +571,14 @@ xfs_attri_validate(
> return false;
>
> if ((attrp->alfi_name_len > XATTR_NAME_MAX) ||
> + (attrp->alfi_nname_len > XATTR_NAME_MAX) ||
> (attrp->alfi_name_len == 0))
> return false;
>
> + if (op == XFS_ATTRI_OP_FLAGS_REMOVE &&
> + attrp->alfi_value_len != 0)
> + return false;
This change fixes a validation flaw in existing code, right?
If so, it ought to be a separate patc... you know what? 26 patches is
enough, I'll let this one slide since LARP is still experimental.
--D
> +
> return xfs_verify_ino(mp, attrp->alfi_ino);
> }
>
> @@ -611,6 +639,8 @@ xfs_attri_item_recover(
> args->whichfork = XFS_ATTR_FORK;
> args->name = nv->name.i_addr;
> args->namelen = nv->name.i_len;
> + args->new_name = nv->nname.i_addr;
> + args->new_namelen = nv->nname.i_len;
> args->hashval = xfs_da_hashname(args->name, args->namelen);
> args->attr_filter = attrp->alfi_attr_filter & XFS_ATTRI_FILTER_MASK;
> args->op_flags = XFS_DA_OP_RECOVERY | XFS_DA_OP_OKNOENT |
> @@ -621,6 +651,7 @@ xfs_attri_item_recover(
> switch (attr->xattri_op_flags) {
> case XFS_ATTRI_OP_FLAGS_SET:
> case XFS_ATTRI_OP_FLAGS_REPLACE:
> + case XFS_ATTRI_OP_FLAGS_NVREPLACE:
> args->value = nv->value.i_addr;
> args->valuelen = nv->value.i_len;
> args->total = xfs_attr_calc_size(args, &local);
> @@ -710,6 +741,7 @@ xfs_attri_item_relog(
> new_attrp->alfi_op_flags = old_attrp->alfi_op_flags;
> new_attrp->alfi_value_len = old_attrp->alfi_value_len;
> new_attrp->alfi_name_len = old_attrp->alfi_name_len;
> + new_attrp->alfi_nname_len = old_attrp->alfi_nname_len;
> new_attrp->alfi_attr_filter = old_attrp->alfi_attr_filter;
>
> xfs_trans_add_item(tp, &new_attrip->attri_item);
> @@ -731,10 +763,41 @@ xlog_recover_attri_commit_pass2(
> struct xfs_attri_log_nameval *nv;
> const void *attr_value = NULL;
> const void *attr_name;
> - int error;
> + const void *attr_nname = NULL;
> + int i = 0;
> + int op, error = 0;
>
> - attri_formatp = item->ri_buf[0].i_addr;
> - attr_name = item->ri_buf[1].i_addr;
> + if (item->ri_total == 0) {
> + XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
> + return -EFSCORRUPTED;
> + }
> +
> + attri_formatp = item->ri_buf[i].i_addr;
> + i++;
> +
> + op = attri_formatp->alfi_op_flags & XFS_ATTRI_OP_FLAGS_TYPE_MASK;
> + switch (op) {
> + case XFS_ATTRI_OP_FLAGS_SET:
> + case XFS_ATTRI_OP_FLAGS_REPLACE:
> + if (item->ri_total != 3)
> + error = -EFSCORRUPTED;
> + break;
> + case XFS_ATTRI_OP_FLAGS_REMOVE:
> + if (item->ri_total != 2)
> + error = -EFSCORRUPTED;
> + break;
> + case XFS_ATTRI_OP_FLAGS_NVREPLACE:
> + if (item->ri_total != 4)
> + error = -EFSCORRUPTED;
> + break;
> + default:
> + error = -EFSCORRUPTED;
> + }
> +
> + if (error) {
> + XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
> + return error;
> + }
>
> /* Validate xfs_attri_log_format before the large memory allocation */
> if (!xfs_attri_validate(mp, attri_formatp)) {
> @@ -742,13 +805,27 @@ xlog_recover_attri_commit_pass2(
> return -EFSCORRUPTED;
> }
>
> + attr_name = item->ri_buf[i].i_addr;
> + i++;
> +
> if (!xfs_attr_namecheck(attr_name, attri_formatp->alfi_name_len)) {
> XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
> return -EFSCORRUPTED;
> }
>
> + if (attri_formatp->alfi_nname_len) {
> + attr_nname = item->ri_buf[i].i_addr;
> + i++;
> +
> + if (!xfs_attr_namecheck(attr_nname,
> + attri_formatp->alfi_nname_len)) {
> + XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
> + return -EFSCORRUPTED;
> + }
> + }
> +
> if (attri_formatp->alfi_value_len)
> - attr_value = item->ri_buf[2].i_addr;
> + attr_value = item->ri_buf[i].i_addr;
>
> /*
> * Memory alloc failure will cause replay to abort. We attach the
> @@ -756,7 +833,8 @@ xlog_recover_attri_commit_pass2(
> * reference.
> */
> nv = xfs_attri_log_nameval_alloc(attr_name,
> - attri_formatp->alfi_name_len, attr_value,
> + attri_formatp->alfi_name_len, attr_nname,
> + attri_formatp->alfi_nname_len, attr_value,
> attri_formatp->alfi_value_len);
>
> attrip = xfs_attri_init(mp, nv);
> diff --git a/fs/xfs/xfs_attr_item.h b/fs/xfs/xfs_attr_item.h
> index 3280a7930287..24d4968dd6cc 100644
> --- a/fs/xfs/xfs_attr_item.h
> +++ b/fs/xfs/xfs_attr_item.h
> @@ -13,6 +13,7 @@ struct kmem_zone;
>
> struct xfs_attri_log_nameval {
> struct xfs_log_iovec name;
> + struct xfs_log_iovec nname;
> struct xfs_log_iovec value;
> refcount_t refcount;
>
> --
> 2.25.1
>
next prev parent reply other threads:[~2022-09-23 18:53 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-22 5:44 [PATCH v3 00/26] Parent Pointers allison.henderson
2022-09-22 5:44 ` [PATCH v3 01/26] xfs: Add new name to attri/d allison.henderson
2022-09-23 18:53 ` Darrick J. Wong [this message]
2022-09-23 20:43 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 02/26] xfs: Increase XFS_DEFER_OPS_NR_INODES to 5 allison.henderson
2022-09-23 19:02 ` Darrick J. Wong
2022-09-23 20:45 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 03/26] xfs: Hold inode locks in xfs_ialloc allison.henderson
2022-09-22 5:44 ` [PATCH v3 04/26] xfs: Hold inode locks in xfs_trans_alloc_dir allison.henderson
2022-09-23 19:04 ` Darrick J. Wong
2022-09-23 20:44 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 05/26] xfs: Hold inode locks in xfs_rename allison.henderson
2022-09-23 19:21 ` Darrick J. Wong
2022-09-23 20:44 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 06/26] xfs: Expose init_xattrs in xfs_create_tmpfile allison.henderson
2022-09-23 19:25 ` Darrick J. Wong
2022-09-23 20:45 ` Allison Henderson
2022-09-23 21:18 ` Darrick J. Wong
2022-09-22 5:44 ` [PATCH v3 07/26] xfs: get directory offset when adding directory name allison.henderson
2022-09-22 5:44 ` [PATCH v3 08/26] xfs: get directory offset when removing " allison.henderson
2022-09-22 5:44 ` [PATCH v3 09/26] xfs: get directory offset when replacing a " allison.henderson
2022-09-22 5:44 ` [PATCH v3 10/26] xfs: add parent pointer support to attribute code allison.henderson
2022-09-22 5:44 ` [PATCH v3 11/26] xfs: define parent pointer xattr format allison.henderson
2022-09-22 5:44 ` [PATCH v3 12/26] xfs: Add xfs_verify_pptr allison.henderson
2022-09-22 5:44 ` [PATCH v3 13/26] xfs: extend transaction reservations for parent attributes allison.henderson
2022-09-23 20:17 ` Darrick J. Wong
2022-09-23 23:53 ` Allison Henderson
2022-09-26 23:53 ` Darrick J. Wong
2022-09-27 20:04 ` Allison Henderson
2022-09-27 20:44 ` Darrick J. Wong
2022-09-22 5:44 ` [PATCH v3 14/26] xfs: parent pointer attribute creation allison.henderson
2022-09-23 21:11 ` Darrick J. Wong
2022-09-26 21:48 ` Allison Henderson
2022-09-26 23:54 ` Darrick J. Wong
2022-09-27 20:10 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 15/26] xfs: add parent attributes to link allison.henderson
2022-09-23 20:31 ` Darrick J. Wong
2022-09-26 21:49 ` Allison Henderson
2022-09-26 23:55 ` Darrick J. Wong
2022-09-22 5:44 ` [PATCH v3 16/26] xfs: add parent attributes to symlink allison.henderson
2022-09-23 21:16 ` Darrick J. Wong
2022-09-26 21:48 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 17/26] xfs: remove parent pointers in unlink allison.henderson
2022-09-23 21:22 ` Darrick J. Wong
2022-09-26 21:49 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 18/26] xfs: Add parent pointers to xfs_cross_rename allison.henderson
2022-09-23 21:52 ` Darrick J. Wong
2022-09-26 21:50 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 19/26] xfs: Indent xfs_rename allison.henderson
2022-09-23 21:22 ` Darrick J. Wong
2022-09-26 21:49 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 20/26] xfs: Add parent pointers to rename allison.henderson
2022-09-23 22:08 ` Darrick J. Wong
2022-09-26 21:50 ` Allison Henderson
2022-09-22 5:44 ` [PATCH v3 21/26] xfs: Add the parent pointer support to the superblock version 5 allison.henderson
2022-09-22 5:44 ` [PATCH v3 22/26] xfs: Add helper function xfs_attr_list_context_init allison.henderson
2022-09-22 5:44 ` [PATCH v3 23/26] xfs: Filter XFS_ATTR_PARENT for getfattr allison.henderson
2022-09-22 16:55 ` Allison Henderson
2022-09-23 21:45 ` Darrick J. Wong
2022-09-26 21:49 ` Allison Henderson
2022-09-27 18:32 ` Darrick J. Wong
2022-09-28 18:22 ` Allison Henderson
2022-09-28 1:13 ` [xfs] b73248c4ee: xfstests.xfs.269.fail kernel test robot
2022-09-22 5:44 ` [PATCH v3 24/26] xfs: Add parent pointer ioctl allison.henderson
2022-09-24 0:30 ` Darrick J. Wong
2022-09-26 21:50 ` Allison Henderson
2022-09-27 18:34 ` Darrick J. Wong
2022-09-22 5:44 ` [PATCH v3 25/26] xfs: fix unit conversion error in xfs_log_calc_max_attrsetm_res allison.henderson
2022-09-23 21:47 ` Darrick J. Wong
2022-09-26 21:50 ` Allison Henderson
2022-09-27 0:02 ` Darrick J. Wong
2022-09-22 5:44 ` [PATCH v3 26/26] xfs: drop compatibility minimum log size computations for reflink allison.henderson
2022-09-23 21:48 ` Darrick J. Wong
2022-09-26 21:50 ` Allison Henderson
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