From patchwork Wed Mar 31 06:50:21 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [1/3] #6823 page reading with mandatory locking style Date: Tue, 30 Mar 2010 20:50:21 -0000 From: piastry@etersoft.ru X-Patchwork-Id: 49083 Message-Id: <201003311050.22864.piastry@etersoft.ru> To: linux-cifs-client@lists.samba.org В сообщении от 28 марта 2010 22:33:35 автор piastry@etersoft.ru написал: > В сообщении от 27 марта 2010 04:57:28 вы написали: > > On Wed, 24 Mar 2010 11:55:31 +0300 > > > > piastry@etersoft.ru wrote: > > > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c > > > index 5183bc2..2b894bd 100644 > > > --- a/fs/cifs/cifsfs.c > > > +++ b/fs/cifs/cifsfs.c > > > @@ -616,6 +616,51 @@ cifs_get_sb(struct file_system_type *fs_type, > > > > > > return 0; > > > > > > } > > > > > > +static ssize_t cifs_sync_read(struct file *filp, char __user *buf, > > > + size_t len, loff_t *ppos) > > > +{ > > > + int retval, read, posix_locking = 0; > > > + struct file_lock pfLock; > > > + struct cifsInodeInfo *cifsInode; > > > + struct cifs_sb_info *cifs_sb; > > > + struct cifsTconInfo *tcon; > > > + > > > + cifs_sb = CIFS_SB(filp->f_path.dentry->d_sb); > > > + tcon = cifs_sb->tcon; > > > + if ((tcon->ses->capabilities & CAP_UNIX) && > > > + (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) > > > && + ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) > > > + posix_locking = 1; > > > + > > > + retval = cifs_revalidate(filp->f_path.dentry); > > > + if (retval < 0) > > > + return (ssize_t)retval; > > > + > > > + memset(&pfLock, 0, sizeof(pfLock)); > > > + pfLock.fl_type = F_RDLCK; > > > + pfLock.fl_start = *ppos; > > > + pfLock.fl_end = *ppos+len; > > > + cifsInode = CIFS_I(filp->f_path.dentry->d_inode); > > > + if (cifsInode == NULL) > > > + return -ENOENT; > > > + > > > + if (!CIFS_I(filp->f_path.dentry->d_inode)->clientCanCacheRead && > > > + !posix_locking) { > > > + retval = cifs_lock(filp, F_GETLK, &pfLock); > > > + if (retval < 0) > > > + return (ssize_t)retval; > > > + if (pfLock.fl_type == F_UNLCK) > > > + read = do_sync_read(filp, buf, len, ppos); > > > + else > > > + return -EACCES; > > > + } else > > > + read = do_sync_read(filp, buf, len, ppos); > > > + > > > + if (read == -EACCES && !posix_locking) > > > + read = cifs_user_read(filp, buf, len, ppos); > > > + return read; > > > +} > > > + > > > > > > static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct > > > iovec *iov, > > > > > > unsigned long nr_segs, loff_t pos) > > > > > > { > > > > > > @@ -737,7 +782,7 @@ const struct inode_operations > > > cifs_symlink_inode_ops = { > > > > > > }; > > > > > > const struct file_operations cifs_file_ops = { > > > > > > - .read = do_sync_read, > > > + .read = cifs_sync_read, > > > > > > .write = do_sync_write, > > > .aio_read = generic_file_aio_read, > > > .aio_write = cifs_file_aio_write, > > > > > > Signed-off-by: Pavel Shilovsky > > > > I have no clue what this patch is intended to do. Can you possibly > > explain it, preferably in a resent patch with proper patch descripion > > and signed-off-by line at the beginning? > > [CIFS] Fix page reading error with mandatory locking style > > If we lock file from one process from 1 to 2 and then try to read it > from another from 0 to 1 without direct mount options, reading fails. > That's why vfs tries to read whole page and fails due the lock from > the first process. > > Signed-off-by: Pavel Shilovsky > > See patch in attachment. > > -- > Best regards, > Pavel Shilovsky. Resend right variant of this patch. --- Best regards, Pavel Shilovsky. From: Pavel Shilovsky [CIFS] Fix page reading error with mandatory locking style If we lock file from one process from 1 to 2 and then try to read it from another from 0 to 1 without direct mount options, reading fails. That's why vfs tries to read whole page and fails due the lock from the first process. Signed-off-by: Pavel Shilovsky --- fs/cifs/cifsfs.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 46 insertions(+), 1 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index ded66be..94a3b1f 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -616,6 +616,51 @@ cifs_get_sb(struct file_system_type *fs_type, return 0; } +static ssize_t cifs_sync_read(struct file *filp, char __user *buf, + size_t len, loff_t *ppos) +{ + int retval, read, posix_locking = 0; + struct file_lock pfLock; + struct cifsInodeInfo *cifsInode; + struct cifs_sb_info *cifs_sb; + struct cifsTconInfo *tcon; + + cifs_sb = CIFS_SB(filp->f_path.dentry->d_sb); + tcon = cifs_sb->tcon; + if ((tcon->ses->capabilities & CAP_UNIX) && + (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) && + ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) + posix_locking = 1; + + retval = cifs_revalidate_file(filp); + if (retval < 0) + return (ssize_t)retval; + + memset(&pfLock, 0, sizeof(pfLock)); + pfLock.fl_type = F_RDLCK; + pfLock.fl_start = *ppos; + pfLock.fl_end = *ppos+len; + cifsInode = CIFS_I(filp->f_path.dentry->d_inode); + if (cifsInode == NULL) + return -ENOENT; + + if (!CIFS_I(filp->f_path.dentry->d_inode)->clientCanCacheRead && + !posix_locking) { + retval = cifs_lock(filp, F_GETLK, &pfLock); + if (retval < 0) + return (ssize_t)retval; + if (pfLock.fl_type == F_UNLCK) + read = do_sync_read(filp, buf, len, ppos); + else + return -EACCES; + } else + read = do_sync_read(filp, buf, len, ppos); + + if (read == -EACCES && !posix_locking) + read = cifs_user_read(filp, buf, len, ppos); + return read; +} + static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { @@ -737,7 +782,7 @@ const struct inode_operations cifs_symlink_inode_ops = { }; const struct file_operations cifs_file_ops = { - .read = do_sync_read, + .read = cifs_sync_read, .write = do_sync_write, .aio_read = generic_file_aio_read, .aio_write = cifs_file_aio_write, -- 1.6.6.1