From 56aa616a03feca630d5afce647367a5d8cfc67b8 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 8 Dec 2009 10:25:33 +0000 Subject: [PATCH 1/4] GFS2: Ensure uptodate inode size when using O_APPEND The VFS reads the inode size during generic_file_aio_write() but with no locking around it. In order to get the expected result from O_APPEND opens, this patch updated the inode size before calling generic_file_aio_write() There is of course still a race here, in that there is nothing to prevent another node coming in and extending the file in the mean time. On the other hand, when used with file locking this will ensure that the expected results are obtained. Signed-off-by: Steven Whitehouse --- fs/gfs2/file.c | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 4eb308aa3234..a6abbae8a278 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -569,6 +569,40 @@ static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync) return ret; } +/** + * gfs2_file_aio_write - Perform a write to a file + * @iocb: The io context + * @iov: The data to write + * @nr_segs: Number of @iov segments + * @pos: The file position + * + * We have to do a lock/unlock here to refresh the inode size for + * O_APPEND writes, otherwise we can land up writing at the wrong + * offset. There is still a race, but provided the app is using its + * own file locking, this will make O_APPEND work as expected. + * + */ + +static ssize_t gfs2_file_aio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + struct file *file = iocb->ki_filp; + + if (file->f_flags & O_APPEND) { + struct dentry *dentry = file->f_dentry; + struct gfs2_inode *ip = GFS2_I(dentry->d_inode); + struct gfs2_holder gh; + int ret; + + ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh); + if (ret) + return ret; + gfs2_glock_dq_uninit(&gh); + } + + return generic_file_aio_write(iocb, iov, nr_segs, pos); +} + #ifdef CONFIG_GFS2_FS_LOCKING_DLM /** @@ -711,7 +745,7 @@ const struct file_operations gfs2_file_fops = { .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, - .aio_write = generic_file_aio_write, + .aio_write = gfs2_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, @@ -741,7 +775,7 @@ const struct file_operations gfs2_file_fops_nolock = { .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, - .aio_write = generic_file_aio_write, + .aio_write = gfs2_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, From 24b977b5fdea09bf356428870d32c09a275c8a3e Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Wed, 9 Dec 2009 13:55:12 +0000 Subject: [PATCH 2/4] GFS2: Fix locking bug in rename The rename code was taking a resource group lock in cases where it wasn't actually needed, this caused problems if the rename was resulting in an inode being unlinked. The patch ensures that we only take the rgrp lock early if it is really needed. Signed-off-by: Steven Whitehouse --- fs/gfs2/ops_inode.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c index 247436c10deb..78f73ca1ef3e 100644 --- a/fs/gfs2/ops_inode.c +++ b/fs/gfs2/ops_inode.c @@ -748,7 +748,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, struct gfs2_rgrpd *nrgd; unsigned int num_gh; int dir_rename = 0; - int alloc_required; + int alloc_required = 0; unsigned int x; int error; @@ -867,7 +867,9 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, goto out_gunlock; } - alloc_required = error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name); + if (nip == NULL) + alloc_required = gfs2_diradd_alloc_required(ndir, &ndentry->d_name); + error = alloc_required; if (error < 0) goto out_gunlock; error = 0; From e412bdb1260d13ec5e7b90b537fec2179d6f8989 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 21 Dec 2009 13:55:28 +0000 Subject: [PATCH 3/4] GFS2: Fix gfs2_xattr_acl_chmod() The ref counting for the bh returned by gfs2_ea_find() was wrong. This patch ensures that we always drop the ref count to that bh correctly. Signed-off-by: Steven Whitehouse --- fs/gfs2/xattr.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c index 8a04108e0c22..c2ebdf2c01d4 100644 --- a/fs/gfs2/xattr.c +++ b/fs/gfs2/xattr.c @@ -1296,6 +1296,7 @@ static int ea_acl_chmod_unstuffed(struct gfs2_inode *ip, int gfs2_xattr_acl_chmod(struct gfs2_inode *ip, struct iattr *attr, char *data) { + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); struct gfs2_ea_location el; struct buffer_head *dibh; int error; @@ -1305,16 +1306,17 @@ int gfs2_xattr_acl_chmod(struct gfs2_inode *ip, struct iattr *attr, char *data) return error; if (GFS2_EA_IS_STUFFED(el.el_ea)) { - error = gfs2_trans_begin(GFS2_SB(&ip->i_inode), RES_DINODE + RES_EATTR, 0); - if (error) - return error; - - gfs2_trans_add_bh(ip->i_gl, el.el_bh, 1); - memcpy(GFS2_EA2DATA(el.el_ea), data, - GFS2_EA_DATA_LEN(el.el_ea)); - } else + error = gfs2_trans_begin(sdp, RES_DINODE + RES_EATTR, 0); + if (error == 0) { + gfs2_trans_add_bh(ip->i_gl, el.el_bh, 1); + memcpy(GFS2_EA2DATA(el.el_ea), data, + GFS2_EA_DATA_LEN(el.el_ea)); + } + } else { error = ea_acl_chmod_unstuffed(ip, el.el_ea, data); + } + brelse(el.el_bh); if (error) return error; @@ -1327,8 +1329,7 @@ int gfs2_xattr_acl_chmod(struct gfs2_inode *ip, struct iattr *attr, char *data) brelse(dibh); } - gfs2_trans_end(GFS2_SB(&ip->i_inode)); - + gfs2_trans_end(sdp); return error; } From ba198098a21a5dc8885fddfb308135bc2f138003 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Fri, 8 Jan 2010 13:44:49 +0000 Subject: [PATCH 4/4] GFS2: Use MAX_LFS_FILESIZE for meta inode size Using ~0ULL was cauing sign issues in filemap_fdatawrite_range, so use MAX_LFS_FILESIZE instead. Signed-off-by: Steven Whitehouse --- fs/gfs2/meta_io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c index cb8d7a93d5ec..6f68a5f18eb8 100644 --- a/fs/gfs2/meta_io.c +++ b/fs/gfs2/meta_io.c @@ -121,7 +121,7 @@ struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp) if (aspace) { mapping_set_gfp_mask(aspace->i_mapping, GFP_NOFS); aspace->i_mapping->a_ops = &aspace_aops; - aspace->i_size = ~0ULL; + aspace->i_size = MAX_LFS_FILESIZE; ip = GFS2_I(aspace); clear_bit(GIF_USER, &ip->i_flags); insert_inode_hash(aspace);