/* * 9p backend * * Copyright IBM, Corp. 2011 * * Authors: * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> * * This work is licensed under the terms of the GNU GPL, version 2. See * the COPYING file in the top-level directory. * */ #include "qemu/osdep.h" #include "fsdev/qemu-fsdev.h" #include "qemu/thread.h" #include "qemu/coroutine.h" #include "coth.h" int coroutine_fn v9fs_co_st_gen(V9fsPDU *pdu, V9fsPath *path, mode_t st_mode, V9fsStatDotl *v9stat) { int err = 0; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } if (s->ctx.exops.get_st_gen) { v9fs_path_read_lock(s); v9fs_co_run_in_worker( { err = s->ctx.exops.get_st_gen(&s->ctx, path, st_mode, &v9stat->st_gen); if (err < 0) { err = -errno; } }); v9fs_path_unlock(s); } return err; } int coroutine_fn v9fs_co_lstat(V9fsPDU *pdu, V9fsPath *path, struct stat *stbuf) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_path_read_lock(s); v9fs_co_run_in_worker( { err = s->ops->lstat(&s->ctx, path, stbuf); if (err < 0) { err = -errno; } }); v9fs_path_unlock(s); return err; } int coroutine_fn v9fs_co_fstat(V9fsPDU *pdu, V9fsFidState *fidp, struct stat *stbuf) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_co_run_in_worker( { err = s->ops->fstat(&s->ctx, fidp->fid_type, &fidp->fs, stbuf); if (err < 0) { err = -errno; } }); /* * Some FS driver (local:mapped-file) can't support fetching attributes * using file descriptor. Use Path name in that case. */ if (err == -EOPNOTSUPP) { err = v9fs_co_lstat(pdu, &fidp->path, stbuf); if (err == -ENOENT) { /* * fstat on an unlinked file. Work with partial results * returned from s->ops->fstat */ err = 0; } } return err; } int coroutine_fn v9fs_co_open(V9fsPDU *pdu, V9fsFidState *fidp, int flags) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_path_read_lock(s); v9fs_co_run_in_worker( { err = s->ops->open(&s->ctx, &fidp->path, flags, &fidp->fs); if (err == -1) { err = -errno; } else { err = 0; } }); v9fs_path_unlock(s); if (!err) { total_open_fd++; if (total_open_fd > open_fd_hw) { v9fs_reclaim_fd(pdu); } } return err; } int coroutine_fn v9fs_co_open2(V9fsPDU *pdu, V9fsFidState *fidp, V9fsString *name, gid_t gid, int flags, int mode, struct stat *stbuf) { int err; FsCred cred; V9fsPath path; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } cred_init(&cred); cred.fc_mode = mode & 07777; cred.fc_uid = fidp->uid; cred.fc_gid = gid; /* * Hold the directory fid lock so that directory path name * don't change. Read lock is fine because this fid cannot * be used by any other operation. */ v9fs_path_read_lock(s); v9fs_co_run_in_worker( { err = s->ops->open2(&s->ctx, &fidp->path, name->data, flags, &cred, &fidp->fs); if (err < 0) { err = -errno; } else { v9fs_path_init(&path); err = v9fs_name_to_path(s, &fidp->path, name->data, &path); if (!err) { err = s->ops->lstat(&s->ctx, &path, stbuf); if (err < 0) { err = -errno; s->ops->close(&s->ctx, &fidp->fs); } else { v9fs_path_copy(&fidp->path, &path); } } else { s->ops->close(&s->ctx, &fidp->fs); } v9fs_path_free(&path); } }); v9fs_path_unlock(s); if (!err) { total_open_fd++; if (total_open_fd > open_fd_hw) { v9fs_reclaim_fd(pdu); } } return err; } int coroutine_fn v9fs_co_close(V9fsPDU *pdu, V9fsFidOpenState *fs) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_co_run_in_worker( { err = s->ops->close(&s->ctx, fs); if (err < 0) { err = -errno; } }); if (!err) { total_open_fd--; } return err; } int coroutine_fn v9fs_co_fsync(V9fsPDU *pdu, V9fsFidState *fidp, int datasync) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_co_run_in_worker( { err = s->ops->fsync(&s->ctx, fidp->fid_type, &fidp->fs, datasync); if (err < 0) { err = -errno; } }); return err; } int coroutine_fn v9fs_co_link(V9fsPDU *pdu, V9fsFidState *oldfid, V9fsFidState *newdirfid, V9fsString *name) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } v9fs_path_read_lock(s); v9fs_co_run_in_worker( { err = s->ops->link(&s->ctx, &oldfid->path, &newdirfid->path, name->data); if (err < 0) { err = -errno; } }); v9fs_path_unlock(s); return err; } int coroutine_fn v9fs_co_pwritev(V9fsPDU *pdu, V9fsFidState *fidp, struct iovec *iov, int iovcnt, int64_t offset) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } fsdev_co_throttle_request(s->ctx.fst, true, iov, iovcnt); v9fs_co_run_in_worker( { err = s->ops->pwritev(&s->ctx, &fidp->fs, iov, iovcnt, offset); if (err < 0) { err = -errno; } }); return err; } int coroutine_fn v9fs_co_preadv(V9fsPDU *pdu, V9fsFidState *fidp, struct iovec *iov, int iovcnt, int64_t offset) { int err; V9fsState *s = pdu->s; if (v9fs_request_cancelled(pdu)) { return -EINTR; } fsdev_co_throttle_request(s->ctx.fst, false, iov, iovcnt); v9fs_co_run_in_worker( { err = s->ops->preadv(&s->ctx, &fidp->fs, iov, iovcnt, offset); if (err < 0) { err = -errno; } }); return err; }