diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 792549193865..780c0e3e4703 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -1042,6 +1042,7 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode) } read_lock(&GlobalSMBSeslock); +refind_writable: list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { if (open_file->closePend) continue; @@ -1049,26 +1050,49 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode) ((open_file->pfile->f_flags & O_RDWR) || (open_file->pfile->f_flags & O_WRONLY))) { atomic_inc(&open_file->wrtPending); + + if (!open_file->invalidHandle) { + /* found a good writable file */ + read_unlock(&GlobalSMBSeslock); + return open_file; + } + read_unlock(&GlobalSMBSeslock); - if (open_file->invalidHandle) { - rc = cifs_reopen_file(open_file->pfile, FALSE); - /* if it fails, try another handle - might be */ - /* dangerous to hold up writepages with retry */ - if (rc) { - cFYI(1, ("wp failed on reopen file")); + /* Had to unlock since following call can block */ + rc = cifs_reopen_file(open_file->pfile, FALSE); + if (!rc) { + if (!open_file->closePend) + return open_file; + else { /* start over in case this was deleted */ + /* since the list could be modified */ read_lock(&GlobalSMBSeslock); - /* can not use this handle, no write - pending on this one after all */ atomic_dec(&open_file->wrtPending); - continue; + goto refind_writable; } } - if (open_file->closePend) { - read_lock(&GlobalSMBSeslock); - atomic_dec(&open_file->wrtPending); - continue; - } - return open_file; + + /* if it fails, try another handle if possible - + (we can not do this if closePending since + loop could be modified - in which case we + have to start at the beginning of the list + again. Note that it would be bad + to hold up writepages here (rather than + in caller) with continuous retries */ + cFYI(1, ("wp failed on reopen file")); + read_lock(&GlobalSMBSeslock); + /* can not use this handle, no write + pending on this one after all */ + atomic_dec(&open_file->wrtPending); + + if (open_file->closePend) /* list could have changed */ + goto refind_writable; + /* else we simply continue to the next entry. Thus + we do not loop on reopen errors. If we + can not reopen the file, for example if we + reconnected to a server with another client + racing to delete or lock the file we would not + make progress if we restarted before the beginning + of the loop here. */ } } read_unlock(&GlobalSMBSeslock);