xfs
[Top] [All Lists]

[PATCH RESEND 2/10] xfs: Add support FALLOC_FL_COLLAPSE_RANGE for falloc

To: viro@xxxxxxxxxxxxxxxxxx, david@xxxxxxxxxxxxx, bpm@xxxxxxx, tytso@xxxxxxx, adilger.kernel@xxxxxxxxx, jack@xxxxxxx, mtk.manpages@xxxxxxxxx
Subject: [PATCH RESEND 2/10] xfs: Add support FALLOC_FL_COLLAPSE_RANGE for fallocate
From: Namjae Jeon <linkinjeon@xxxxxxxxx>
Date: Sun, 2 Feb 2014 14:44:11 +0900
Cc: linux-fsdevel@xxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx, linux-ext4@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, Namjae Jeon <linkinjeon@xxxxxxxxx>, Namjae Jeon <namjae.jeon@xxxxxxxxxxx>, Ashish Sangwan <a.sangwan@xxxxxxxxxxx>
Delivered-to: xfs@xxxxxxxxxxx
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=foX+JX9OBb4phAodbuJyFbQPgLc4jaLJLWwF0jpQCcg=; b=J4uVpR8XpuLEgSoDPbBBA8Atb//0p/fF07Q3C/XhwPyg4LM3LqOxcHBkfGNNx9M9Ml Pwzm1v0QAZx/G+Z7ki/gBZmMHljIOZIsbgpuF6ZFEIDYEKgLZr1BSkWsEMsdi0iwqT0H RNz+CXY8+hzTc+qnOmtZE1Atb1obhmmg0j+1h6KitaZQ0ANqw5FUuc4XdztOTTa2bfqb TxCnFD9Dbo08oxorF85PQGaSu9a/IX9fjrJh06bXqw1HNv9BBX72oS3qZf/aTSfskPFo 78dKUEsYb7L+L78kTMWUaI5HhC2V/wp0nHcoGjWH5Z2/vyi7dvl7oTW9Egv2+FVN+2ze D3fA==
From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>

Add support FALLOC_FL_COLLAPSE_RANGE for fallocate.

Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx>
Signed-off-by: Ashish Sangwan <a.sangwan@xxxxxxxxxxx>
---
 fs/xfs/xfs_bmap.c      |  195 ++++++++++++++++++++++++++++++++++++++++++++++++
 fs/xfs/xfs_bmap.h      |    5 ++
 fs/xfs/xfs_bmap_util.c |   99 ++++++++++++++++++++++++
 fs/xfs/xfs_bmap_util.h |    2 +
 fs/xfs/xfs_file.c      |   19 ++++-
 fs/xfs/xfs_trace.h     |    1 +
 6 files changed, 319 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 3ef11b2..aba3fc9 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -5358,3 +5358,198 @@ error0:
        }
        return error;
 }
+
+/*
+ * Shift extent records to the left to cover a hole.
+ *
+ * The maximum number of extents to be shifted in a single operation
+ * is @num_exts, and @current_ext keeps track of the current extent
+ * index we have shifted. @offset_shift_fsb is the length by which each
+ * extent is shifted. If there is no hole to shift the extents
+ * into, this will be considered invalid operation and we abort immediately.
+ */
+int
+xfs_bmap_shift_extents(
+       struct xfs_trans        *tp,
+       struct xfs_inode        *ip,
+       int                     *done,
+       xfs_fileoff_t           start_fsb,
+       xfs_fileoff_t           offset_shift_fsb,
+       xfs_extnum_t            *current_ext,
+       xfs_fsblock_t           *firstblock,
+       struct xfs_bmap_free    *flist,
+       int                     num_exts)
+{
+       struct xfs_btree_cur            *cur;
+       struct xfs_bmbt_rec_host        *gotp;
+       struct xfs_bmbt_irec            got;
+       struct xfs_bmbt_irec            left;
+       struct xfs_mount                *mp = ip->i_mount;
+       struct xfs_ifork                *ifp;
+       xfs_extnum_t                    nexts = 0;
+       xfs_fileoff_t                   startoff;
+       int                             error = 0;
+       int                             i;
+       int                             whichfork = XFS_DATA_FORK;
+       int                             logflags;
+       xfs_filblks_t                   blockcount = 0;
+
+       if (unlikely(XFS_TEST_ERROR(
+           (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
+            XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
+            mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
+               XFS_ERROR_REPORT("xfs_bmap_shift_extents",
+                                XFS_ERRLEVEL_LOW, mp);
+               return XFS_ERROR(EFSCORRUPTED);
+       }
+
+       if (XFS_FORCED_SHUTDOWN(mp))
+               return XFS_ERROR(EIO);
+
+       ASSERT(current_ext != NULL);
+
+       ifp = XFS_IFORK_PTR(ip, whichfork);
+
+       if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+               /* Read in all the extents */
+               error = xfs_iread_extents(tp, ip, whichfork);
+               if (error)
+                       return error;
+       }
+
+       /*
+        * If *current_ext is 0, we would need to lookup the extent
+        * from where we would start shifting and store it in gotp.
+        */
+       if (!*current_ext) {
+               gotp = xfs_iext_bno_to_ext(ifp, start_fsb, current_ext);
+               /*
+                * gotp can be null in 2 cases: 1) if there are no extents
+                * or 2) start_fsb lies in a hole beyond which there are
+                * no extents. Either way, we are done.
+                */
+               if (!gotp) {
+                       *done = 1;
+                       return 0;
+               }
+       }
+
+       /* We are going to change core inode */
+       logflags = XFS_ILOG_CORE;
+
+       if (ifp->if_flags & XFS_IFBROOT) {
+               cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
+               cur->bc_private.b.firstblock = *firstblock;
+               cur->bc_private.b.flist = flist;
+               cur->bc_private.b.flags = 0;
+       } else {
+               cur = NULL;
+               logflags |= XFS_ILOG_DEXT;
+       }
+
+       while (nexts++ < num_exts &&
+              *current_ext <  XFS_IFORK_NEXTENTS(ip, whichfork)) {
+
+               gotp = xfs_iext_get_ext(ifp, *current_ext);
+               xfs_bmbt_get_all(gotp, &got);
+               startoff = got.br_startoff - offset_shift_fsb;
+
+               /*
+                * Before shifting extent into hole, make sure that the hole
+                * is large enough to accomodate the shift.
+                */
+               if (*current_ext) {
+                       xfs_bmbt_get_all(xfs_iext_get_ext(ifp,
+                                               *current_ext - 1), &left);
+
+                       if (startoff < left.br_startoff + left.br_blockcount)
+                               error = XFS_ERROR(EINVAL);
+
+               } else if (startoff > xfs_bmbt_get_startoff(gotp)) {
+                       /* Hole is at the start but not large enough */
+                       error = XFS_ERROR(EINVAL);
+               }
+
+               if (error)
+                       goto del_cursor;
+
+               if (cur) {
+                       error = xfs_bmbt_lookup_eq(cur,
+                                       got.br_startoff,
+                                       got.br_startblock,
+                                       got.br_blockcount,
+                                       &i);
+                       if (error)
+                               goto del_cursor;
+                       XFS_WANT_CORRUPTED_GOTO(i == 1, del_cursor);
+               }
+
+               /* Check if we can merge 2 adjacent extents */
+               if (*current_ext &&
+                   left.br_startoff + left.br_blockcount == startoff &&
+                   left.br_startblock + left.br_blockcount ==
+                               got.br_startblock &&
+                   left.br_state == got.br_state &&
+                   left.br_blockcount + got.br_blockcount <= MAXEXTLEN) {
+                       blockcount = left.br_blockcount +
+                               xfs_bmbt_get_blockcount(gotp);
+                       xfs_iext_remove(ip, *current_ext, 1, 0);
+                       if (cur) {
+                               error = xfs_btree_delete(cur, &i);
+                               if (error)
+                                       goto del_cursor;
+                               XFS_WANT_CORRUPTED_GOTO(i == 1, del_cursor);
+                       }
+                       XFS_IFORK_NEXT_SET(ip, whichfork,
+                               XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
+                       gotp = xfs_iext_get_ext(ifp, --*current_ext);
+                       xfs_bmbt_get_all(gotp, &got);
+
+                       /* Make cursor point to the extent we will update */
+                       if (cur) {
+                               error = xfs_bmbt_lookup_eq(cur,
+                               got.br_startoff,
+                               got.br_startblock,
+                               got.br_blockcount,
+                               &i);
+                               if (error)
+                                       goto del_cursor;
+                               XFS_WANT_CORRUPTED_GOTO(i == 1, del_cursor);
+                       }
+
+                       xfs_bmbt_set_blockcount(gotp, blockcount);
+                       got.br_blockcount = blockcount;
+                       goto bmbt_update;
+               }
+
+               /* We have to update the startoff */
+               xfs_bmbt_set_startoff(gotp, startoff);
+               got.br_startoff = startoff;
+
+bmbt_update:
+               if (cur) {
+                       error = xfs_bmbt_update(cur,
+                                       got.br_startoff,
+                                       got.br_startblock,
+                                       got.br_blockcount,
+                                       got.br_state);
+                       if (error)
+                               goto del_cursor;
+               }
+
+               (*current_ext)++;
+       }
+
+       /* Check if we are done */
+       if (*current_ext ==  XFS_IFORK_NEXTENTS(ip, whichfork))
+               *done = 1;
+
+del_cursor:
+       if (cur)
+               xfs_btree_del_cursor(cur,
+                       error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+
+       xfs_trans_log_inode(tp, ip, logflags);
+
+       return error;
+}
diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h
index 33b41f3..7bfe67c 100644
--- a/fs/xfs/xfs_bmap.h
+++ b/fs/xfs/xfs_bmap.h
@@ -169,5 +169,10 @@ int        xfs_bunmapi(struct xfs_trans *tp, struct 
xfs_inode *ip,
 int    xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
                xfs_extnum_t num);
 uint   xfs_default_attroffset(struct xfs_inode *ip);
+int    xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
+               int *done, xfs_fileoff_t start_fsb,
+               xfs_fileoff_t offset_shift_fsb, xfs_extnum_t *current_ext,
+               xfs_fsblock_t *firstblock, struct xfs_bmap_free *flist,
+               int num_exts);
 
 #endif /* __XFS_BMAP_H__ */
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 5887e41..7b62f5d 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1446,6 +1446,105 @@ out:
 }
 
 /*
+ * xfs_collapse_file_space()
+ *      This routine frees disk space and shift extent for the given file.
+ *
+ * RETURNS:
+ *      0 on success
+ *      errno on error
+ *
+ */
+int
+xfs_collapse_file_space(
+       struct xfs_inode        *ip,
+       xfs_off_t               offset,
+       xfs_off_t               len)
+{
+       int                     done = 0;
+       struct xfs_mount        *mp = ip->i_mount;
+       struct xfs_trans        *tp;
+       int                     error;
+       xfs_extnum_t            current_ext = 0;
+       struct xfs_bmap_free    free_list;
+       xfs_fsblock_t           first_block;
+       int                     committed;
+       xfs_fileoff_t           start_fsb;
+       xfs_fileoff_t           shift_fsb;
+
+       ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
+
+       trace_xfs_collapse_file_space(ip);
+
+       start_fsb = XFS_B_TO_FSB(mp, offset + len);
+       shift_fsb = XFS_B_TO_FSB(mp, len);
+
+       /*
+        * The first thing we do is to free data blocks in the specified range
+        * by calling xfs_free_file_space(). It would also sync dirty data
+        * and invalidate page cache over the region on which collapse range
+        * is working.
+        */
+
+       error = xfs_free_file_space(ip, offset, len);
+       if (error)
+               return error;
+
+       while (!error && !done) {
+               tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
+               tp->t_flags |= XFS_TRANS_RESERVE;
+               /*
+                * We would need to reserve permanent block for transaction.
+                * This will come into picture when after shifting extent into
+                * hole we found that adjacent extents can be merged which
+                * may lead to freeing of a block during record update.
+                */
+               error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
+                               XFS_DIOSTRAT_SPACE_RES(mp, 0), 0);
+               if (error) {
+                       ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
+                       xfs_trans_cancel(tp, 0);
+                       break;
+               }
+
+               xfs_ilock(ip, XFS_ILOCK_EXCL);
+               error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
+                               ip->i_gdquot, ip->i_pdquot,
+                               XFS_DIOSTRAT_SPACE_RES(mp, 0), 0,
+                               XFS_QMOPT_RES_REGBLKS);
+               if (error)
+                       goto out;
+
+               xfs_trans_ijoin(tp, ip, 0);
+
+               xfs_bmap_init(&free_list, &first_block);
+
+               /*
+                * We are using the write transaction in which max 2 bmbt
+                * updates are allowed
+                */
+               error = xfs_bmap_shift_extents(tp, ip, &done, start_fsb,
+                               shift_fsb, &current_ext,
+                               &first_block, &free_list, 2);
+               if (error)
+                       goto out;
+
+               error = xfs_bmap_finish(&tp, &free_list, &committed);
+               if (error)
+                       goto out;
+
+               error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
+               xfs_iunlock(ip, XFS_ILOCK_EXCL);
+       }
+
+       return error;
+
+out:
+       xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
+       xfs_iunlock(ip, XFS_ILOCK_EXCL);
+       return error;
+}
+
+/*
  * We need to check that the format of the data fork in the temporary inode is
  * valid for the target inode before doing the swap. This is not a problem with
  * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
index 900747b..935ed2b 100644
--- a/fs/xfs/xfs_bmap_util.h
+++ b/fs/xfs/xfs_bmap_util.h
@@ -99,6 +99,8 @@ int   xfs_free_file_space(struct xfs_inode *ip, xfs_off_t 
offset,
                            xfs_off_t len);
 int    xfs_zero_file_space(struct xfs_inode *ip, xfs_off_t offset,
                            xfs_off_t len);
+int    xfs_collapse_file_space(struct xfs_inode *, xfs_off_t offset,
+                               xfs_off_t len);
 
 /* EOF block manipulation functions */
 bool   xfs_can_free_eofblocks(struct xfs_inode *ip, bool force);
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 52c91e1..accb25b 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -820,7 +820,8 @@ xfs_file_fallocate(
 
        if (!S_ISREG(inode->i_mode))
                return -EINVAL;
-       if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+       if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
+                    FALLOC_FL_COLLAPSE_RANGE))
                return -EOPNOTSUPP;
 
        xfs_ilock(ip, XFS_IOLOCK_EXCL);
@@ -828,6 +829,20 @@ xfs_file_fallocate(
                error = xfs_free_file_space(ip, offset, len);
                if (error)
                        goto out_unlock;
+       } else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
+               unsigned blksize_mask = (1 << inode->i_blkbits) - 1;
+
+               if (offset & blksize_mask || len & blksize_mask) {
+                       error = -EINVAL;
+                       goto out_unlock;
+               }
+
+               ASSERT(offset + len < i_size_read(inode));
+               new_size = i_size_read(inode) - len;
+
+               error = xfs_collapse_file_space(ip, offset, len);
+               if (error)
+                       goto out_unlock;
        } else {
                if (!(mode & FALLOC_FL_KEEP_SIZE) &&
                    offset + len > i_size_read(inode)) {
@@ -856,7 +871,7 @@ xfs_file_fallocate(
        if (ip->i_d.di_mode & S_IXGRP)
                ip->i_d.di_mode &= ~S_ISGID;
 
-       if (!(mode & FALLOC_FL_PUNCH_HOLE))
+       if (!(mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE)))
                ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
 
        xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 425dfa4..a4ae41c 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -603,6 +603,7 @@ DEFINE_INODE_EVENT(xfs_readlink);
 DEFINE_INODE_EVENT(xfs_inactive_symlink);
 DEFINE_INODE_EVENT(xfs_alloc_file_space);
 DEFINE_INODE_EVENT(xfs_free_file_space);
+DEFINE_INODE_EVENT(xfs_collapse_file_space);
 DEFINE_INODE_EVENT(xfs_readdir);
 #ifdef CONFIG_XFS_POSIX_ACL
 DEFINE_INODE_EVENT(xfs_get_acl);
-- 
1.7.9.5

<Prev in Thread] Current Thread [Next in Thread>