diff options
| -rw-r--r-- | fs/cifs/cifsfs.c | 1 | ||||
| -rw-r--r-- | fs/cifs/cifsglob.h | 1 | ||||
| -rw-r--r-- | fs/cifs/file.c | 94 |
3 files changed, 65 insertions, 31 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index c6e32f2..210f0af 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -229,6 +229,7 @@ cifs_alloc_inode(struct super_block *sb) cifs_set_oplock_level(cifs_inode, 0); cifs_inode->delete_pending = false; cifs_inode->invalid_mapping = false; + cifs_inode->leave_pages_clean = false; cifs_inode->vfs_inode.i_blkbits = 14; /* 2**14 = CIFS_MAX_MSGSIZE */ cifs_inode->server_eof = 0; cifs_inode->uniqueid = 0; diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index dfab450..aea1eec 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1030,6 +1030,7 @@ struct cifsInodeInfo { bool clientCanCacheAll; /* read and writebehind oplock */ bool delete_pending; /* DELETE_ON_CLOSE is set */ bool invalid_mapping; /* pagecache is invalid */ + bool leave_pages_clean; /* protected by i_mutex, not set pages dirty */ unsigned long time; /* jiffies of last update of inode */ u64 server_eof; /* current file size on server -- protected by i_lock */ u64 uniqueid; /* server inode number */ diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 1b322d0..0a6677b 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2103,7 +2103,15 @@ static int cifs_write_end(struct file *file, struct address_space *mapping, } else { rc = copied; pos += copied; - set_page_dirty(page); + /* + * When we use strict cache mode and cifs_strict_writev was run + * with level II oplock (indicated by leave_pages_clean field of + * CIFS_I(inode)), we can leave pages clean - cifs_strict_writev + * sent the data to the server itself. + */ + if (!CIFS_I(inode)->leave_pages_clean || + !(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)) + set_page_dirty(page); } if (rc > 0) { @@ -2454,8 +2462,8 @@ ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov, } static ssize_t -cifs_writev(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t pos) +cifs_pagecache_writev(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos, bool cache_ex) { struct file *file = iocb->ki_filp; struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data; @@ -2477,8 +2485,12 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov, server->vals->exclusive_lock_type, NULL, CIFS_WRITE_OP)) { mutex_lock(&inode->i_mutex); + if (!cache_ex) + cinode->leave_pages_clean = true; rc = __generic_file_aio_write(iocb, iov, nr_segs, - &iocb->ki_pos); + &iocb->ki_pos); + if (!cache_ex) + cinode->leave_pages_clean = false; mutex_unlock(&inode->i_mutex); } @@ -2505,42 +2517,62 @@ cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov, struct cifsFileInfo *cfile = (struct cifsFileInfo *) iocb->ki_filp->private_data; struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); - -#ifdef CONFIG_CIFS_SMB2 + ssize_t written, written2; /* - * If we have an oplock for read and want to write a data to the file - * we need to store it in the page cache and then push it to the server - * to be sure the next read will get a valid data. + * We need to store clientCanCacheAll here to prevent race + * conditions - this value can be changed during an execution + * of generic_file_aio_write. For CIFS it can be changed from + * true to false only, but for SMB2 it can be changed both from + * true to false and vice versa. So, we can end up with a data + * stored in the cache, not marked dirty and not sent to the + * server if this value changes its state from false to true + * after cifs_write_end. */ - if (!cinode->clientCanCacheAll && cinode->clientCanCacheRead) { - ssize_t written; - int rc; - - written = generic_file_aio_write(iocb, iov, nr_segs, pos); - rc = filemap_fdatawrite(inode->i_mapping); - if (rc) - return (ssize_t)rc; + bool cache_ex = cinode->clientCanCacheAll; + bool cache_read = cinode->clientCanCacheRead; + int rc; + loff_t saved_pos; - return written; + if (cache_ex) { + if (cap_unix(tcon->ses) && + ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) && + (CIFS_UNIX_FCNTL_CAP & le64_to_cpu( + tcon->fsUnixInfo.Capability))) + return generic_file_aio_write(iocb, iov, nr_segs, pos); + return cifs_pagecache_writev(iocb, iov, nr_segs, pos, cache_ex); } -#endif /* - * For non-oplocked files in strict cache mode we need to write the data - * to the server exactly from the pos to pos+len-1 rather than flush all - * affected pages because it may cause a error with mandatory locks on - * these pages but not on the region from pos to ppos+len-1. + * For files without exclusive oplock in strict cache mode we need to + * write the data to the server exactly from the pos to pos+len-1 rather + * than flush all affected pages because it may cause a error with + * mandatory locks on these pages but not on the region from pos to + * ppos+len-1. */ + written = cifs_user_writev(iocb, iov, nr_segs, pos); + if (!cache_read || written <= 0) + return written; - if (!cinode->clientCanCacheAll) - return cifs_user_writev(iocb, iov, nr_segs, pos); - + saved_pos = iocb->ki_pos; + iocb->ki_pos = pos; + /* we have a read oplock - need to store a data in the page cache */ if (cap_unix(tcon->ses) && - (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) && - ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) - return generic_file_aio_write(iocb, iov, nr_segs, pos); - - return cifs_writev(iocb, iov, nr_segs, pos); + ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) && + (CIFS_UNIX_FCNTL_CAP & le64_to_cpu( + tcon->fsUnixInfo.Capability))) + written2 = generic_file_aio_write(iocb, iov, nr_segs, pos); + else + written2 = cifs_pagecache_writev(iocb, iov, nr_segs, pos, + cache_ex); + /* errors occured during writing - invalidate the page cache */ + if (written2 < 0) { + rc = cifs_invalidate_mapping(inode); + if (rc) + written = (ssize_t)rc; + else + iocb->ki_pos = saved_pos; + } + return written; } static struct cifs_readdata * |
