diff --git a/lib/libc/sys/fspacectl.2 b/lib/libc/sys/fspacectl.2 index 0e369785b883..430f3de950df 100644 --- a/lib/libc/sys/fspacectl.2 +++ b/lib/libc/sys/fspacectl.2 @@ -1,206 +1,205 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD .\" .\" Copyright (c) 2021 The FreeBSD Foundation .\" .\" This manual page was written by Ka Ho Ng under sponsorship from .\" the FreeBSD Foundation. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd August 18, 2021 +.Dd August 25, 2021 .Dt FSPACECTL 2 .Os .Sh NAME .Nm fspacectl .Nd space management in a file .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In fcntl.h .Ft int .Fo fspacectl .Fa "int fd" .Fa "int cmd" .Fa "const struct spacectl_range *rqsr" .Fa "int flags" .Fa "struct spacectl_range *rmsr" .Fc .Sh DESCRIPTION .Nm is a system call performing space management over a file. The .Fa fd argument specifies the file descriptor to be operated on by the .Fa cmd argument. The .Fa rqsr argument points to a .Fa spacectl_range structure that contains the requested operation range. The .Fa flags argument controls the behavior of the operation to take place. If the .Fa rmsr argument is non-NULL, the .Fa spacectl_range structure it points to is updated to contain the unprocessed operation range after the system call returns. .Pp For a successful completion without an unprocessed part in the requested operation range, .Fa "rmsr->r_len" is updated to be the value 0, and .Fa "rmsr->r_offset" -is updated to be the smallest of -.Fa "rqsr->r_offset" + -.Fa "rqsr->r_len" ; -and the end-of-file offset. +is updated to be +.Fa "rqsr->r_offset" +plus the number of bytes zeroed before the end-of-file. The file descriptor's file offset is not used or modified by the system call. Both .Fa rqsr and .Fa rmsr arguments can point to the same structure. .Pp The .Fa spacectl_range structure is defined as: .Bd -literal struct spacectl_range { off_t r_offset; off_t r_len; }; .Ed .Pp The operation specified by the .Fa cmd argument may be one of: .Bl -tag -width SPACECTL_DEALLOC .It Dv SPACECTL_DEALLOC Zero a region in the file specified by the .Fa rqsr argument. The .Fa "rqsr->r_offset" has to be a value greater than or equal to 0, and the .Fa "rqsr->r_len" has to be a value greater than 0. .Pp If the file system supports hole-punching, file system space deallocation may be performed in the given region. .El .Pp The .Fa flags argument needs to be the value 0 currently. .Sh RETURN VALUES Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and .Va errno is set to indicate the error. .Sh ERRORS Possible failure conditions: .Bl -tag -width Er .It Bq Er EBADF The .Fa fd argument is not a valid file descriptor. .It Bq Er EBADF The .Fa fd argument references a file that was opened without write permission. .It Bq Er EINTR A signal was caught during execution. .It Bq Er EINVAL The .Fa cmd argument is not valid. .It Bq Er EINVAL If the .Fa cmd argument is .Dv SPACECTL_DEALLOC , either the .Fa "rqsr->r_offset" argument was less than zero, or the .Fa "rqsr->r_len" argument was less than or equal to zero. .It Bq Er EINVAL The value of .Fa "rqsr->r_offset" + .Fa "rqsr->r_len" is greater than .Dv OFF_MAX . .It Bq Er EINVAL An invalid or unsupported flag is included in .Fa flags . .It Bq Er EINVAL A flag included in .Fa flags is not supported by the operation specified by the .Fa cmd argument. .It Bq Er EFAULT The .Fa rqsr or a non-NULL .Fa rmsr argument point outside the process' allocated address space. .It Bq Er EIO An I/O error occurred while reading from or writing to a file system. .It Bq Er EINTEGRITY Corrupted data was detected while reading from the file system. .It Bq Er ENODEV The .Fa fd argument does not refer to a file that supports .Nm . .It Bq Er ENOSPC There is insufficient free space remaining on the file system storage media. .It Bq Er ENOTCAPABLE The file descriptor .Fa fd has insufficient rights. .It Bq Er ESPIPE The .Fa fd argument is associated with a pipe or FIFO. .El .Sh SEE ALSO .Xr creat 2 , .Xr ftruncate 2 , .Xr open 2 , .Xr unlink 2 .Sh HISTORY The .Nm system call appeared in .Fx 14.0 . .Sh AUTHORS .Nm and this manual page were written by .An Ka Ho Ng Aq Mt khng@FreeBSD.org under sponsorship from the FreeBSD Foundation. diff --git a/share/man/man9/VOP_DEALLOCATE.9 b/share/man/man9/VOP_DEALLOCATE.9 index 2ec915c6fef3..d20fe1590314 100644 --- a/share/man/man9/VOP_DEALLOCATE.9 +++ b/share/man/man9/VOP_DEALLOCATE.9 @@ -1,112 +1,109 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD .\" .\" Copyright (c) 2021 The FreeBSD Foundation .\" .\" This manual page was written by Ka Ho Ng under sponsorship from .\" the FreeBSD Foundation. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd August 11, 2021 +.Dd August 25, 2021 .Dt VOP_DEALLOCATE 9 .Os .Sh NAME .Nm VOP_DEALLOCATE .Nd zero and/or deallocate storage from a file .Sh SYNOPSIS .In sys/param.h .In sys/vnode.h .Ft int .Fo VOP_DEALLOCATE .Fa "struct vnode *vp" .Fa "off_t *offset" .Fa "off_t *len" .Fa "int flags" .Fa "int ioflag" .Fa "struct ucred *cred" .Fc .Sh DESCRIPTION This VOP call zeroes/deallocates storage for an offset range in a file. It is used to implement the .Xr fspacectl 2 system call. .Pp Its arguments are: .Bl -tag -width offset .It Fa vp The vnode of the file. .It Fa offset The start of the range to deallocate storage in the file. .It Fa len The length of the range to deallocate storage in the file. .It Fa flags The flags of this call. This should be set to 0 for now. .It Fa ioflag Directives and hints to be given to the file system. .It Fa cred The credentials of the caller. .El .Pp .Fa *offset and .Fa *len are updated to reflect the portion of the range that still needs to be zeroed/deallocated on return. Partial result is considered a successful operation. -For a successful completion without an unprocessed portion of the range, +For a non-partial successful completion, .Fa *len is updated to be the value 0, and .Fa *offset -is updated to be the smallest of -.Fa *offset + -.Fa *len -passed to the call and the end-of-file offset. +is incremented by the number of bytes zeroed before the end-of-file. .Sh LOCKS The vnode should be locked on entry and will still be locked on exit. .Sh RETURN VALUES Zero is returned if the call is successful, otherwise an appropriate error code is returned. .Sh ERRORS .Bl -tag -width Er .It Bq Er EINVAL Invalid .Fa offset , len or .Fa flags parameters are passed into this VOP call. .It Bq Er ENODEV The vnode type is not supported by this VOP call. .It Bq Er ENOSPC The file system is full. .It Bq Er EPERM An append-only flag is set on the file, but the caller is attempting to zero before the current end of file. .El .Sh SEE ALSO .Xr vnode 9 .Sh AUTHORS .Nm and this manual page was written by .An Ka Ho Ng Aq Mt khng@FreeBSD.org under sponsorship from the FreeBSD Foundation. diff --git a/share/man/man9/vn_deallocate.9 b/share/man/man9/vn_deallocate.9 index 08f4e92ec597..ce1515ddaaa1 100644 --- a/share/man/man9/vn_deallocate.9 +++ b/share/man/man9/vn_deallocate.9 @@ -1,116 +1,113 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD .\" .\" Copyright (c) 2021 The FreeBSD Foundation .\" .\" This manual page was written by Ka Ho Ng under sponsorship from .\" the FreeBSD Foundation. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd August 11, 2021 +.Dd August 25, 2021 .Dt VN_DEALLOCATE 9 .Os .Sh NAME .Nm vn_deallocate .Nd zero and/or deallocate storage from a file .Sh SYNOPSIS .In sys/param.h .In sys/vnode.h .Ft int .Fo vn_deallocate .Fa "struct vnode *vp" .Fa "off_t *offset" .Fa "off_t *length" .Fa "int flags" .Fa "int ioflag" .Fa "struct ucred *active_cred" .Fa "struct ucred *file_cred" .Fc .Sh DESCRIPTION The .Fn vn_deallocate function zeros and/or deallocates backing storage space from a file. This function only works on vnodes with .Dv VREG type. .Pp The arguments are: .Bl -tag -width active_cred .It Fa vp The vnode of the file. .It Fa offset The starting offset of the operation range. .It Fa length The length of the operation range. This must be greater than 0. .It Fa flags The control flags of the operation. This should be set to 0 for now. .It Fa ioflag Directives and hints to be given to the file system. .It Fa active_cred The user credentials of the calling thread. .It Fa file_cred The credentials installed on the file description pointing to the vnode or NOCRED. .El .Pp The .Fn ioflag argument gives directives and hints to the file system. It may include one or more of the following flags: .Bl -tag -width IO_RANGELOCKED .It Dv IO_NODELOCKED The vnode was locked before the call. .It Dv IO_RANGELOCKED Rangelock was owned around the call. .It Dv IO_NOMACCHECK Skip MAC checking in the call. .It Dv IO_SYNC Do I/O synchronously. .It Dv IO_DIRECT Attempt to bypass buffer cache. .El .Pp .Fa *offset and .Fa *length are updated to reflect the unprocessed operation range of the call. For a successful completion, .Fa *length is updated to be the value 0, and .Fa *offset -is updated to be the smallest of -.Fa *offset + -.Fa *length -passed to the call and the end-of-file offset. +is incremented by the number of bytes zeroed before the end-of-file. .Sh RETURN VALUES Upon successful completion, the value 0 is returned; otherwise the appropriate error is returned. .Sh SEE ALSO .Xr vnode 9 , .Xr VOP_DEALLOCATE 9 .Sh AUTHORS .Nm and this manual page was written by .An Ka Ho Ng Aq Mt khng@FreeBSD.org under sponsorship from the FreeBSD Foundation. diff --git a/sys/kern/uipc_shm.c b/sys/kern/uipc_shm.c index c632c7f150df..c672c0477b95 100644 --- a/sys/kern/uipc_shm.c +++ b/sys/kern/uipc_shm.c @@ -1,2099 +1,2098 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2006, 2011, 2016-2017 Robert N. M. Watson * Copyright 2020 The FreeBSD Foundation * All rights reserved. * * Portions of this software were developed by BAE Systems, the University of * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent * Computing (TC) research program. * * Portions of this software were developed by Konstantin Belousov * under sponsorship from the FreeBSD Foundation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Support for shared swap-backed anonymous memory objects via * shm_open(2), shm_rename(2), and shm_unlink(2). * While most of the implementation is here, vm_mmap.c contains * mapping logic changes. * * posixshmcontrol(1) allows users to inspect the state of the memory * objects. Per-uid swap resource limit controls total amount of * memory that user can consume for anonymous objects, including * shared. */ #include __FBSDID("$FreeBSD$"); #include "opt_capsicum.h" #include "opt_ktrace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct shm_mapping { char *sm_path; Fnv32_t sm_fnv; struct shmfd *sm_shmfd; LIST_ENTRY(shm_mapping) sm_link; }; static MALLOC_DEFINE(M_SHMFD, "shmfd", "shared memory file descriptor"); static LIST_HEAD(, shm_mapping) *shm_dictionary; static struct sx shm_dict_lock; static struct mtx shm_timestamp_lock; static u_long shm_hash; static struct unrhdr64 shm_ino_unr; static dev_t shm_dev_ino; #define SHM_HASH(fnv) (&shm_dictionary[(fnv) & shm_hash]) static void shm_init(void *arg); static void shm_insert(char *path, Fnv32_t fnv, struct shmfd *shmfd); static struct shmfd *shm_lookup(char *path, Fnv32_t fnv); static int shm_remove(char *path, Fnv32_t fnv, struct ucred *ucred); static int shm_dotruncate_cookie(struct shmfd *shmfd, off_t length, void *rl_cookie); static int shm_dotruncate_locked(struct shmfd *shmfd, off_t length, void *rl_cookie); static int shm_copyin_path(struct thread *td, const char *userpath_in, char **path_out); static int shm_deallocate(struct shmfd *shmfd, off_t *offset, off_t *length, int flags); static fo_rdwr_t shm_read; static fo_rdwr_t shm_write; static fo_truncate_t shm_truncate; static fo_ioctl_t shm_ioctl; static fo_stat_t shm_stat; static fo_close_t shm_close; static fo_chmod_t shm_chmod; static fo_chown_t shm_chown; static fo_seek_t shm_seek; static fo_fill_kinfo_t shm_fill_kinfo; static fo_mmap_t shm_mmap; static fo_get_seals_t shm_get_seals; static fo_add_seals_t shm_add_seals; static fo_fallocate_t shm_fallocate; static fo_fspacectl_t shm_fspacectl; /* File descriptor operations. */ struct fileops shm_ops = { .fo_read = shm_read, .fo_write = shm_write, .fo_truncate = shm_truncate, .fo_ioctl = shm_ioctl, .fo_poll = invfo_poll, .fo_kqfilter = invfo_kqfilter, .fo_stat = shm_stat, .fo_close = shm_close, .fo_chmod = shm_chmod, .fo_chown = shm_chown, .fo_sendfile = vn_sendfile, .fo_seek = shm_seek, .fo_fill_kinfo = shm_fill_kinfo, .fo_mmap = shm_mmap, .fo_get_seals = shm_get_seals, .fo_add_seals = shm_add_seals, .fo_fallocate = shm_fallocate, .fo_fspacectl = shm_fspacectl, .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE, }; FEATURE(posix_shm, "POSIX shared memory"); static SYSCTL_NODE(_vm, OID_AUTO, largepages, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, ""); static int largepage_reclaim_tries = 1; SYSCTL_INT(_vm_largepages, OID_AUTO, reclaim_tries, CTLFLAG_RWTUN, &largepage_reclaim_tries, 0, "Number of contig reclaims before giving up for default alloc policy"); static int uiomove_object_page(vm_object_t obj, size_t len, struct uio *uio) { vm_page_t m; vm_pindex_t idx; size_t tlen; int error, offset, rv; idx = OFF_TO_IDX(uio->uio_offset); offset = uio->uio_offset & PAGE_MASK; tlen = MIN(PAGE_SIZE - offset, len); rv = vm_page_grab_valid_unlocked(&m, obj, idx, VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY | VM_ALLOC_NOCREAT); if (rv == VM_PAGER_OK) goto found; /* * Read I/O without either a corresponding resident page or swap * page: use zero_region. This is intended to avoid instantiating * pages on read from a sparse region. */ VM_OBJECT_WLOCK(obj); m = vm_page_lookup(obj, idx); if (uio->uio_rw == UIO_READ && m == NULL && !vm_pager_has_page(obj, idx, NULL, NULL)) { VM_OBJECT_WUNLOCK(obj); return (uiomove(__DECONST(void *, zero_region), tlen, uio)); } /* * Although the tmpfs vnode lock is held here, it is * nonetheless safe to sleep waiting for a free page. The * pageout daemon does not need to acquire the tmpfs vnode * lock to page out tobj's pages because tobj is a OBJT_SWAP * type object. */ rv = vm_page_grab_valid(&m, obj, idx, VM_ALLOC_NORMAL | VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY); if (rv != VM_PAGER_OK) { VM_OBJECT_WUNLOCK(obj); printf("uiomove_object: vm_obj %p idx %jd pager error %d\n", obj, idx, rv); return (EIO); } VM_OBJECT_WUNLOCK(obj); found: error = uiomove_fromphys(&m, offset, tlen, uio); if (uio->uio_rw == UIO_WRITE && error == 0) vm_page_set_dirty(m); vm_page_activate(m); vm_page_sunbusy(m); return (error); } int uiomove_object(vm_object_t obj, off_t obj_size, struct uio *uio) { ssize_t resid; size_t len; int error; error = 0; while ((resid = uio->uio_resid) > 0) { if (obj_size <= uio->uio_offset) break; len = MIN(obj_size - uio->uio_offset, resid); if (len == 0) break; error = uiomove_object_page(obj, len, uio); if (error != 0 || resid == uio->uio_resid) break; } return (error); } static u_long count_largepages[MAXPAGESIZES]; static int shm_largepage_phys_populate(vm_object_t object, vm_pindex_t pidx, int fault_type, vm_prot_t max_prot, vm_pindex_t *first, vm_pindex_t *last) { vm_page_t m; int psind; psind = object->un_pager.phys.data_val; if (psind == 0 || pidx >= object->size) return (VM_PAGER_FAIL); *first = rounddown2(pidx, pagesizes[psind] / PAGE_SIZE); /* * We only busy the first page in the superpage run. It is * useless to busy whole run since we only remove full * superpage, and it takes too long to busy e.g. 512 * 512 == * 262144 pages constituing 1G amd64 superage. */ m = vm_page_grab(object, *first, VM_ALLOC_NORMAL | VM_ALLOC_NOCREAT); MPASS(m != NULL); *last = *first + atop(pagesizes[psind]) - 1; return (VM_PAGER_OK); } static boolean_t shm_largepage_phys_haspage(vm_object_t object, vm_pindex_t pindex, int *before, int *after) { int psind; psind = object->un_pager.phys.data_val; if (psind == 0 || pindex >= object->size) return (FALSE); if (before != NULL) { *before = pindex - rounddown2(pindex, pagesizes[psind] / PAGE_SIZE); } if (after != NULL) { *after = roundup2(pindex, pagesizes[psind] / PAGE_SIZE) - pindex; } return (TRUE); } static void shm_largepage_phys_ctor(vm_object_t object, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred) { } static void shm_largepage_phys_dtor(vm_object_t object) { int psind; psind = object->un_pager.phys.data_val; if (psind != 0) { atomic_subtract_long(&count_largepages[psind], object->size / (pagesizes[psind] / PAGE_SIZE)); vm_wire_sub(object->size); } else { KASSERT(object->size == 0, ("largepage phys obj %p not initialized bit size %#jx > 0", object, (uintmax_t)object->size)); } } static const struct phys_pager_ops shm_largepage_phys_ops = { .phys_pg_populate = shm_largepage_phys_populate, .phys_pg_haspage = shm_largepage_phys_haspage, .phys_pg_ctor = shm_largepage_phys_ctor, .phys_pg_dtor = shm_largepage_phys_dtor, }; bool shm_largepage(struct shmfd *shmfd) { return (shmfd->shm_object->type == OBJT_PHYS); } static int shm_seek(struct file *fp, off_t offset, int whence, struct thread *td) { struct shmfd *shmfd; off_t foffset; int error; shmfd = fp->f_data; foffset = foffset_lock(fp, 0); error = 0; switch (whence) { case L_INCR: if (foffset < 0 || (offset > 0 && foffset > OFF_MAX - offset)) { error = EOVERFLOW; break; } offset += foffset; break; case L_XTND: if (offset > 0 && shmfd->shm_size > OFF_MAX - offset) { error = EOVERFLOW; break; } offset += shmfd->shm_size; break; case L_SET: break; default: error = EINVAL; } if (error == 0) { if (offset < 0 || offset > shmfd->shm_size) error = EINVAL; else td->td_uretoff.tdu_off = offset; } foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0); return (error); } static int shm_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags, struct thread *td) { struct shmfd *shmfd; void *rl_cookie; int error; shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_read(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif foffset_lock_uio(fp, uio, flags); rl_cookie = rangelock_rlock(&shmfd->shm_rl, uio->uio_offset, uio->uio_offset + uio->uio_resid, &shmfd->shm_mtx); error = uiomove_object(shmfd->shm_object, shmfd->shm_size, uio); rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); foffset_unlock_uio(fp, uio, flags); return (error); } static int shm_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags, struct thread *td) { struct shmfd *shmfd; void *rl_cookie; int error; off_t size; shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_write(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif if (shm_largepage(shmfd) && shmfd->shm_lp_psind == 0) return (EINVAL); foffset_lock_uio(fp, uio, flags); if (uio->uio_resid > OFF_MAX - uio->uio_offset) { /* * Overflow is only an error if we're supposed to expand on * write. Otherwise, we'll just truncate the write to the * size of the file, which can only grow up to OFF_MAX. */ if ((shmfd->shm_flags & SHM_GROW_ON_WRITE) != 0) { foffset_unlock_uio(fp, uio, flags); return (EFBIG); } size = shmfd->shm_size; } else { size = uio->uio_offset + uio->uio_resid; } if ((flags & FOF_OFFSET) == 0) { rl_cookie = rangelock_wlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); } else { rl_cookie = rangelock_wlock(&shmfd->shm_rl, uio->uio_offset, size, &shmfd->shm_mtx); } if ((shmfd->shm_seals & F_SEAL_WRITE) != 0) { error = EPERM; } else { error = 0; if ((shmfd->shm_flags & SHM_GROW_ON_WRITE) != 0 && size > shmfd->shm_size) { error = shm_dotruncate_cookie(shmfd, size, rl_cookie); } if (error == 0) error = uiomove_object(shmfd->shm_object, shmfd->shm_size, uio); } rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); foffset_unlock_uio(fp, uio, flags); return (error); } static int shm_truncate(struct file *fp, off_t length, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; #ifdef MAC int error; #endif shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_truncate(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif return (shm_dotruncate(shmfd, length)); } int shm_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; struct shm_largepage_conf *conf; void *rl_cookie; shmfd = fp->f_data; switch (com) { case FIONBIO: case FIOASYNC: /* * Allow fcntl(fd, F_SETFL, O_NONBLOCK) to work, * just like it would on an unlinked regular file */ return (0); case FIOSSHMLPGCNF: if (!shm_largepage(shmfd)) return (ENOTTY); conf = data; if (shmfd->shm_lp_psind != 0 && conf->psind != shmfd->shm_lp_psind) return (EINVAL); if (conf->psind <= 0 || conf->psind >= MAXPAGESIZES || pagesizes[conf->psind] == 0) return (EINVAL); if (conf->alloc_policy != SHM_LARGEPAGE_ALLOC_DEFAULT && conf->alloc_policy != SHM_LARGEPAGE_ALLOC_NOWAIT && conf->alloc_policy != SHM_LARGEPAGE_ALLOC_HARD) return (EINVAL); rl_cookie = rangelock_wlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); shmfd->shm_lp_psind = conf->psind; shmfd->shm_lp_alloc_policy = conf->alloc_policy; shmfd->shm_object->un_pager.phys.data_val = conf->psind; rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (0); case FIOGSHMLPGCNF: if (!shm_largepage(shmfd)) return (ENOTTY); conf = data; rl_cookie = rangelock_rlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); conf->psind = shmfd->shm_lp_psind; conf->alloc_policy = shmfd->shm_lp_alloc_policy; rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (0); default: return (ENOTTY); } } static int shm_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; #ifdef MAC int error; #endif shmfd = fp->f_data; #ifdef MAC error = mac_posixshm_check_stat(active_cred, fp->f_cred, shmfd); if (error) return (error); #endif /* * Attempt to return sanish values for fstat() on a memory file * descriptor. */ bzero(sb, sizeof(*sb)); sb->st_blksize = PAGE_SIZE; sb->st_size = shmfd->shm_size; sb->st_blocks = howmany(sb->st_size, sb->st_blksize); mtx_lock(&shm_timestamp_lock); sb->st_atim = shmfd->shm_atime; sb->st_ctim = shmfd->shm_ctime; sb->st_mtim = shmfd->shm_mtime; sb->st_birthtim = shmfd->shm_birthtime; sb->st_mode = S_IFREG | shmfd->shm_mode; /* XXX */ sb->st_uid = shmfd->shm_uid; sb->st_gid = shmfd->shm_gid; mtx_unlock(&shm_timestamp_lock); sb->st_dev = shm_dev_ino; sb->st_ino = shmfd->shm_ino; sb->st_nlink = shmfd->shm_object->ref_count; sb->st_blocks = shmfd->shm_object->size / (pagesizes[shmfd->shm_lp_psind] >> PAGE_SHIFT); return (0); } static int shm_close(struct file *fp, struct thread *td) { struct shmfd *shmfd; shmfd = fp->f_data; fp->f_data = NULL; shm_drop(shmfd); return (0); } static int shm_copyin_path(struct thread *td, const char *userpath_in, char **path_out) { int error; char *path; const char *pr_path; size_t pr_pathlen; path = malloc(MAXPATHLEN, M_SHMFD, M_WAITOK); pr_path = td->td_ucred->cr_prison->pr_path; /* Construct a full pathname for jailed callers. */ pr_pathlen = strcmp(pr_path, "/") == 0 ? 0 : strlcpy(path, pr_path, MAXPATHLEN); error = copyinstr(userpath_in, path + pr_pathlen, MAXPATHLEN - pr_pathlen, NULL); if (error != 0) goto out; #ifdef KTRACE if (KTRPOINT(curthread, KTR_NAMEI)) ktrnamei(path); #endif /* Require paths to start with a '/' character. */ if (path[pr_pathlen] != '/') { error = EINVAL; goto out; } *path_out = path; out: if (error != 0) free(path, M_SHMFD); return (error); } static int shm_partial_page_invalidate(vm_object_t object, vm_pindex_t idx, int base, int end) { vm_page_t m; int rv; VM_OBJECT_ASSERT_WLOCKED(object); KASSERT(base >= 0, ("%s: base %d", __func__, base)); KASSERT(end - base <= PAGE_SIZE, ("%s: base %d end %d", __func__, base, end)); retry: m = vm_page_grab(object, idx, VM_ALLOC_NOCREAT); if (m != NULL) { MPASS(vm_page_all_valid(m)); } else if (vm_pager_has_page(object, idx, NULL, NULL)) { m = vm_page_alloc(object, idx, VM_ALLOC_NORMAL | VM_ALLOC_WAITFAIL); if (m == NULL) goto retry; vm_object_pip_add(object, 1); VM_OBJECT_WUNLOCK(object); rv = vm_pager_get_pages(object, &m, 1, NULL, NULL); VM_OBJECT_WLOCK(object); vm_object_pip_wakeup(object); if (rv == VM_PAGER_OK) { /* * Since the page was not resident, and therefore not * recently accessed, immediately enqueue it for * asynchronous laundering. The current operation is * not regarded as an access. */ vm_page_launder(m); } else { vm_page_free(m); VM_OBJECT_WUNLOCK(object); return (EIO); } } if (m != NULL) { pmap_zero_page_area(m, base, end - base); KASSERT(vm_page_all_valid(m), ("%s: page %p is invalid", __func__, m)); vm_page_set_dirty(m); vm_page_xunbusy(m); } return (0); } static int shm_dotruncate_locked(struct shmfd *shmfd, off_t length, void *rl_cookie) { vm_object_t object; vm_pindex_t nobjsize; vm_ooffset_t delta; int base, error; KASSERT(length >= 0, ("shm_dotruncate: length < 0")); object = shmfd->shm_object; VM_OBJECT_ASSERT_WLOCKED(object); rangelock_cookie_assert(rl_cookie, RA_WLOCKED); if (length == shmfd->shm_size) return (0); nobjsize = OFF_TO_IDX(length + PAGE_MASK); /* Are we shrinking? If so, trim the end. */ if (length < shmfd->shm_size) { if ((shmfd->shm_seals & F_SEAL_SHRINK) != 0) return (EPERM); /* * Disallow any requests to shrink the size if this * object is mapped into the kernel. */ if (shmfd->shm_kmappings > 0) return (EBUSY); /* * Zero the truncated part of the last page. */ base = length & PAGE_MASK; if (base != 0) { error = shm_partial_page_invalidate(object, OFF_TO_IDX(length), base, PAGE_SIZE); if (error) return (error); } delta = IDX_TO_OFF(object->size - nobjsize); if (nobjsize < object->size) vm_object_page_remove(object, nobjsize, object->size, 0); /* Free the swap accounted for shm */ swap_release_by_cred(delta, object->cred); object->charge -= delta; } else { if ((shmfd->shm_seals & F_SEAL_GROW) != 0) return (EPERM); /* Try to reserve additional swap space. */ delta = IDX_TO_OFF(nobjsize - object->size); if (!swap_reserve_by_cred(delta, object->cred)) return (ENOMEM); object->charge += delta; } shmfd->shm_size = length; mtx_lock(&shm_timestamp_lock); vfs_timestamp(&shmfd->shm_ctime); shmfd->shm_mtime = shmfd->shm_ctime; mtx_unlock(&shm_timestamp_lock); object->size = nobjsize; return (0); } static int shm_dotruncate_largepage(struct shmfd *shmfd, off_t length, void *rl_cookie) { vm_object_t object; vm_page_t m; vm_pindex_t newobjsz, oldobjsz; int aflags, error, i, psind, try; KASSERT(length >= 0, ("shm_dotruncate: length < 0")); object = shmfd->shm_object; VM_OBJECT_ASSERT_WLOCKED(object); rangelock_cookie_assert(rl_cookie, RA_WLOCKED); oldobjsz = object->size; newobjsz = OFF_TO_IDX(length); if (length == shmfd->shm_size) return (0); psind = shmfd->shm_lp_psind; if (psind == 0 && length != 0) return (EINVAL); if ((length & (pagesizes[psind] - 1)) != 0) return (EINVAL); if (length < shmfd->shm_size) { if ((shmfd->shm_seals & F_SEAL_SHRINK) != 0) return (EPERM); if (shmfd->shm_kmappings > 0) return (EBUSY); return (ENOTSUP); /* Pages are unmanaged. */ #if 0 vm_object_page_remove(object, newobjsz, oldobjsz, 0); object->size = newobjsz; shmfd->shm_size = length; return (0); #endif } if ((shmfd->shm_seals & F_SEAL_GROW) != 0) return (EPERM); aflags = VM_ALLOC_NORMAL | VM_ALLOC_ZERO; if (shmfd->shm_lp_alloc_policy == SHM_LARGEPAGE_ALLOC_NOWAIT) aflags |= VM_ALLOC_WAITFAIL; try = 0; /* * Extend shmfd and object, keeping all already fully * allocated large pages intact even on error, because dropped * object lock might allowed mapping of them. */ while (object->size < newobjsz) { m = vm_page_alloc_contig(object, object->size, aflags, pagesizes[psind] / PAGE_SIZE, 0, ~0, pagesizes[psind], 0, VM_MEMATTR_DEFAULT); if (m == NULL) { VM_OBJECT_WUNLOCK(object); if (shmfd->shm_lp_alloc_policy == SHM_LARGEPAGE_ALLOC_NOWAIT || (shmfd->shm_lp_alloc_policy == SHM_LARGEPAGE_ALLOC_DEFAULT && try >= largepage_reclaim_tries)) { VM_OBJECT_WLOCK(object); return (ENOMEM); } error = vm_page_reclaim_contig(aflags, pagesizes[psind] / PAGE_SIZE, 0, ~0, pagesizes[psind], 0) ? 0 : vm_wait_intr(object); if (error != 0) { VM_OBJECT_WLOCK(object); return (error); } try++; VM_OBJECT_WLOCK(object); continue; } try = 0; for (i = 0; i < pagesizes[psind] / PAGE_SIZE; i++) { if ((m[i].flags & PG_ZERO) == 0) pmap_zero_page(&m[i]); vm_page_valid(&m[i]); vm_page_xunbusy(&m[i]); } object->size += OFF_TO_IDX(pagesizes[psind]); shmfd->shm_size += pagesizes[psind]; atomic_add_long(&count_largepages[psind], 1); vm_wire_add(atop(pagesizes[psind])); } return (0); } static int shm_dotruncate_cookie(struct shmfd *shmfd, off_t length, void *rl_cookie) { int error; VM_OBJECT_WLOCK(shmfd->shm_object); error = shm_largepage(shmfd) ? shm_dotruncate_largepage(shmfd, length, rl_cookie) : shm_dotruncate_locked(shmfd, length, rl_cookie); VM_OBJECT_WUNLOCK(shmfd->shm_object); return (error); } int shm_dotruncate(struct shmfd *shmfd, off_t length) { void *rl_cookie; int error; rl_cookie = rangelock_wlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); error = shm_dotruncate_cookie(shmfd, length, rl_cookie); rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (error); } /* * shmfd object management including creation and reference counting * routines. */ struct shmfd * shm_alloc(struct ucred *ucred, mode_t mode, bool largepage) { struct shmfd *shmfd; shmfd = malloc(sizeof(*shmfd), M_SHMFD, M_WAITOK | M_ZERO); shmfd->shm_size = 0; shmfd->shm_uid = ucred->cr_uid; shmfd->shm_gid = ucred->cr_gid; shmfd->shm_mode = mode; if (largepage) { shmfd->shm_object = phys_pager_allocate(NULL, &shm_largepage_phys_ops, NULL, shmfd->shm_size, VM_PROT_DEFAULT, 0, ucred); shmfd->shm_lp_alloc_policy = SHM_LARGEPAGE_ALLOC_DEFAULT; } else { shmfd->shm_object = vm_pager_allocate(OBJT_SWAP, NULL, shmfd->shm_size, VM_PROT_DEFAULT, 0, ucred); } KASSERT(shmfd->shm_object != NULL, ("shm_create: vm_pager_allocate")); vfs_timestamp(&shmfd->shm_birthtime); shmfd->shm_atime = shmfd->shm_mtime = shmfd->shm_ctime = shmfd->shm_birthtime; shmfd->shm_ino = alloc_unr64(&shm_ino_unr); refcount_init(&shmfd->shm_refs, 1); mtx_init(&shmfd->shm_mtx, "shmrl", NULL, MTX_DEF); rangelock_init(&shmfd->shm_rl); #ifdef MAC mac_posixshm_init(shmfd); mac_posixshm_create(ucred, shmfd); #endif return (shmfd); } struct shmfd * shm_hold(struct shmfd *shmfd) { refcount_acquire(&shmfd->shm_refs); return (shmfd); } void shm_drop(struct shmfd *shmfd) { if (refcount_release(&shmfd->shm_refs)) { #ifdef MAC mac_posixshm_destroy(shmfd); #endif rangelock_destroy(&shmfd->shm_rl); mtx_destroy(&shmfd->shm_mtx); vm_object_deallocate(shmfd->shm_object); free(shmfd, M_SHMFD); } } /* * Determine if the credentials have sufficient permissions for a * specified combination of FREAD and FWRITE. */ int shm_access(struct shmfd *shmfd, struct ucred *ucred, int flags) { accmode_t accmode; int error; accmode = 0; if (flags & FREAD) accmode |= VREAD; if (flags & FWRITE) accmode |= VWRITE; mtx_lock(&shm_timestamp_lock); error = vaccess(VREG, shmfd->shm_mode, shmfd->shm_uid, shmfd->shm_gid, accmode, ucred); mtx_unlock(&shm_timestamp_lock); return (error); } static void shm_init(void *arg) { char name[32]; int i; mtx_init(&shm_timestamp_lock, "shm timestamps", NULL, MTX_DEF); sx_init(&shm_dict_lock, "shm dictionary"); shm_dictionary = hashinit(1024, M_SHMFD, &shm_hash); new_unrhdr64(&shm_ino_unr, 1); shm_dev_ino = devfs_alloc_cdp_inode(); KASSERT(shm_dev_ino > 0, ("shm dev inode not initialized")); for (i = 1; i < MAXPAGESIZES; i++) { if (pagesizes[i] == 0) break; #define M (1024 * 1024) #define G (1024 * M) if (pagesizes[i] >= G) snprintf(name, sizeof(name), "%luG", pagesizes[i] / G); else if (pagesizes[i] >= M) snprintf(name, sizeof(name), "%luM", pagesizes[i] / M); else snprintf(name, sizeof(name), "%lu", pagesizes[i]); #undef G #undef M SYSCTL_ADD_ULONG(NULL, SYSCTL_STATIC_CHILDREN(_vm_largepages), OID_AUTO, name, CTLFLAG_RD, &count_largepages[i], "number of non-transient largepages allocated"); } } SYSINIT(shm_init, SI_SUB_SYSV_SHM, SI_ORDER_ANY, shm_init, NULL); /* * Dictionary management. We maintain an in-kernel dictionary to map * paths to shmfd objects. We use the FNV hash on the path to store * the mappings in a hash table. */ static struct shmfd * shm_lookup(char *path, Fnv32_t fnv) { struct shm_mapping *map; LIST_FOREACH(map, SHM_HASH(fnv), sm_link) { if (map->sm_fnv != fnv) continue; if (strcmp(map->sm_path, path) == 0) return (map->sm_shmfd); } return (NULL); } static void shm_insert(char *path, Fnv32_t fnv, struct shmfd *shmfd) { struct shm_mapping *map; map = malloc(sizeof(struct shm_mapping), M_SHMFD, M_WAITOK); map->sm_path = path; map->sm_fnv = fnv; map->sm_shmfd = shm_hold(shmfd); shmfd->shm_path = path; LIST_INSERT_HEAD(SHM_HASH(fnv), map, sm_link); } static int shm_remove(char *path, Fnv32_t fnv, struct ucred *ucred) { struct shm_mapping *map; int error; LIST_FOREACH(map, SHM_HASH(fnv), sm_link) { if (map->sm_fnv != fnv) continue; if (strcmp(map->sm_path, path) == 0) { #ifdef MAC error = mac_posixshm_check_unlink(ucred, map->sm_shmfd); if (error) return (error); #endif error = shm_access(map->sm_shmfd, ucred, FREAD | FWRITE); if (error) return (error); map->sm_shmfd->shm_path = NULL; LIST_REMOVE(map, sm_link); shm_drop(map->sm_shmfd); free(map->sm_path, M_SHMFD); free(map, M_SHMFD); return (0); } } return (ENOENT); } int kern_shm_open2(struct thread *td, const char *userpath, int flags, mode_t mode, int shmflags, struct filecaps *fcaps, const char *name __unused) { struct pwddesc *pdp; struct shmfd *shmfd; struct file *fp; char *path; void *rl_cookie; Fnv32_t fnv; mode_t cmode; int error, fd, initial_seals; bool largepage; if ((shmflags & ~(SHM_ALLOW_SEALING | SHM_GROW_ON_WRITE | SHM_LARGEPAGE)) != 0) return (EINVAL); initial_seals = F_SEAL_SEAL; if ((shmflags & SHM_ALLOW_SEALING) != 0) initial_seals &= ~F_SEAL_SEAL; #ifdef CAPABILITY_MODE /* * shm_open(2) is only allowed for anonymous objects. */ if (IN_CAPABILITY_MODE(td) && (userpath != SHM_ANON)) return (ECAPMODE); #endif AUDIT_ARG_FFLAGS(flags); AUDIT_ARG_MODE(mode); if ((flags & O_ACCMODE) != O_RDONLY && (flags & O_ACCMODE) != O_RDWR) return (EINVAL); if ((flags & ~(O_ACCMODE | O_CREAT | O_EXCL | O_TRUNC | O_CLOEXEC)) != 0) return (EINVAL); largepage = (shmflags & SHM_LARGEPAGE) != 0; if (largepage && !PMAP_HAS_LARGEPAGES) return (ENOTTY); /* * Currently only F_SEAL_SEAL may be set when creating or opening shmfd. * If the decision is made later to allow additional seals, care must be * taken below to ensure that the seals are properly set if the shmfd * already existed -- this currently assumes that only F_SEAL_SEAL can * be set and doesn't take further precautions to ensure the validity of * the seals being added with respect to current mappings. */ if ((initial_seals & ~F_SEAL_SEAL) != 0) return (EINVAL); pdp = td->td_proc->p_pd; cmode = (mode & ~pdp->pd_cmask) & ACCESSPERMS; /* * shm_open(2) created shm should always have O_CLOEXEC set, as mandated * by POSIX. We allow it to be unset here so that an in-kernel * interface may be written as a thin layer around shm, optionally not * setting CLOEXEC. For shm_open(2), O_CLOEXEC is set unconditionally * in sys_shm_open() to keep this implementation compliant. */ error = falloc_caps(td, &fp, &fd, flags & O_CLOEXEC, fcaps); if (error) return (error); /* A SHM_ANON path pointer creates an anonymous object. */ if (userpath == SHM_ANON) { /* A read-only anonymous object is pointless. */ if ((flags & O_ACCMODE) == O_RDONLY) { fdclose(td, fp, fd); fdrop(fp, td); return (EINVAL); } shmfd = shm_alloc(td->td_ucred, cmode, largepage); shmfd->shm_seals = initial_seals; shmfd->shm_flags = shmflags; } else { error = shm_copyin_path(td, userpath, &path); if (error != 0) { fdclose(td, fp, fd); fdrop(fp, td); return (error); } AUDIT_ARG_UPATH1_CANON(path); fnv = fnv_32_str(path, FNV1_32_INIT); sx_xlock(&shm_dict_lock); shmfd = shm_lookup(path, fnv); if (shmfd == NULL) { /* Object does not yet exist, create it if requested. */ if (flags & O_CREAT) { #ifdef MAC error = mac_posixshm_check_create(td->td_ucred, path); if (error == 0) { #endif shmfd = shm_alloc(td->td_ucred, cmode, largepage); shmfd->shm_seals = initial_seals; shmfd->shm_flags = shmflags; shm_insert(path, fnv, shmfd); #ifdef MAC } #endif } else { free(path, M_SHMFD); error = ENOENT; } } else { rl_cookie = rangelock_wlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); /* * kern_shm_open() likely shouldn't ever error out on * trying to set a seal that already exists, unlike * F_ADD_SEALS. This would break terribly as * shm_open(2) actually sets F_SEAL_SEAL to maintain * historical behavior where the underlying file could * not be sealed. */ initial_seals &= ~shmfd->shm_seals; /* * Object already exists, obtain a new * reference if requested and permitted. */ free(path, M_SHMFD); /* * initial_seals can't set additional seals if we've * already been set F_SEAL_SEAL. If F_SEAL_SEAL is set, * then we've already removed that one from * initial_seals. This is currently redundant as we * only allow setting F_SEAL_SEAL at creation time, but * it's cheap to check and decreases the effort required * to allow additional seals. */ if ((shmfd->shm_seals & F_SEAL_SEAL) != 0 && initial_seals != 0) error = EPERM; else if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) error = EEXIST; else if (shmflags != 0 && shmflags != shmfd->shm_flags) error = EINVAL; else { #ifdef MAC error = mac_posixshm_check_open(td->td_ucred, shmfd, FFLAGS(flags & O_ACCMODE)); if (error == 0) #endif error = shm_access(shmfd, td->td_ucred, FFLAGS(flags & O_ACCMODE)); } /* * Truncate the file back to zero length if * O_TRUNC was specified and the object was * opened with read/write. */ if (error == 0 && (flags & (O_ACCMODE | O_TRUNC)) == (O_RDWR | O_TRUNC)) { VM_OBJECT_WLOCK(shmfd->shm_object); #ifdef MAC error = mac_posixshm_check_truncate( td->td_ucred, fp->f_cred, shmfd); if (error == 0) #endif error = shm_dotruncate_locked(shmfd, 0, rl_cookie); VM_OBJECT_WUNLOCK(shmfd->shm_object); } if (error == 0) { /* * Currently we only allow F_SEAL_SEAL to be * set initially. As noted above, this would * need to be reworked should that change. */ shmfd->shm_seals |= initial_seals; shm_hold(shmfd); } rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); } sx_xunlock(&shm_dict_lock); if (error) { fdclose(td, fp, fd); fdrop(fp, td); return (error); } } finit(fp, FFLAGS(flags & O_ACCMODE), DTYPE_SHM, shmfd, &shm_ops); td->td_retval[0] = fd; fdrop(fp, td); return (0); } /* System calls. */ #ifdef COMPAT_FREEBSD12 int freebsd12_shm_open(struct thread *td, struct freebsd12_shm_open_args *uap) { return (kern_shm_open(td, uap->path, uap->flags | O_CLOEXEC, uap->mode, NULL)); } #endif int sys_shm_unlink(struct thread *td, struct shm_unlink_args *uap) { char *path; Fnv32_t fnv; int error; error = shm_copyin_path(td, uap->path, &path); if (error != 0) return (error); AUDIT_ARG_UPATH1_CANON(path); fnv = fnv_32_str(path, FNV1_32_INIT); sx_xlock(&shm_dict_lock); error = shm_remove(path, fnv, td->td_ucred); sx_xunlock(&shm_dict_lock); free(path, M_SHMFD); return (error); } int sys_shm_rename(struct thread *td, struct shm_rename_args *uap) { char *path_from = NULL, *path_to = NULL; Fnv32_t fnv_from, fnv_to; struct shmfd *fd_from; struct shmfd *fd_to; int error; int flags; flags = uap->flags; AUDIT_ARG_FFLAGS(flags); /* * Make sure the user passed only valid flags. * If you add a new flag, please add a new term here. */ if ((flags & ~( SHM_RENAME_NOREPLACE | SHM_RENAME_EXCHANGE )) != 0) { error = EINVAL; goto out; } /* * EXCHANGE and NOREPLACE don't quite make sense together. Let's * force the user to choose one or the other. */ if ((flags & SHM_RENAME_NOREPLACE) != 0 && (flags & SHM_RENAME_EXCHANGE) != 0) { error = EINVAL; goto out; } /* Renaming to or from anonymous makes no sense */ if (uap->path_from == SHM_ANON || uap->path_to == SHM_ANON) { error = EINVAL; goto out; } error = shm_copyin_path(td, uap->path_from, &path_from); if (error != 0) goto out; error = shm_copyin_path(td, uap->path_to, &path_to); if (error != 0) goto out; AUDIT_ARG_UPATH1_CANON(path_from); AUDIT_ARG_UPATH2_CANON(path_to); /* Rename with from/to equal is a no-op */ if (strcmp(path_from, path_to) == 0) goto out; fnv_from = fnv_32_str(path_from, FNV1_32_INIT); fnv_to = fnv_32_str(path_to, FNV1_32_INIT); sx_xlock(&shm_dict_lock); fd_from = shm_lookup(path_from, fnv_from); if (fd_from == NULL) { error = ENOENT; goto out_locked; } fd_to = shm_lookup(path_to, fnv_to); if ((flags & SHM_RENAME_NOREPLACE) != 0 && fd_to != NULL) { error = EEXIST; goto out_locked; } /* * Unconditionally prevents shm_remove from invalidating the 'from' * shm's state. */ shm_hold(fd_from); error = shm_remove(path_from, fnv_from, td->td_ucred); /* * One of my assumptions failed if ENOENT (e.g. locking didn't * protect us) */ KASSERT(error != ENOENT, ("Our shm disappeared during shm_rename: %s", path_from)); if (error != 0) { shm_drop(fd_from); goto out_locked; } /* * If we are exchanging, we need to ensure the shm_remove below * doesn't invalidate the dest shm's state. */ if ((flags & SHM_RENAME_EXCHANGE) != 0 && fd_to != NULL) shm_hold(fd_to); /* * NOTE: if path_to is not already in the hash, c'est la vie; * it simply means we have nothing already at path_to to unlink. * That is the ENOENT case. * * If we somehow don't have access to unlink this guy, but * did for the shm at path_from, then relink the shm to path_from * and abort with EACCES. * * All other errors: that is weird; let's relink and abort the * operation. */ error = shm_remove(path_to, fnv_to, td->td_ucred); if (error != 0 && error != ENOENT) { shm_insert(path_from, fnv_from, fd_from); shm_drop(fd_from); /* Don't free path_from now, since the hash references it */ path_from = NULL; goto out_locked; } error = 0; shm_insert(path_to, fnv_to, fd_from); /* Don't free path_to now, since the hash references it */ path_to = NULL; /* We kept a ref when we removed, and incremented again in insert */ shm_drop(fd_from); KASSERT(fd_from->shm_refs > 0, ("Expected >0 refs; got: %d\n", fd_from->shm_refs)); if ((flags & SHM_RENAME_EXCHANGE) != 0 && fd_to != NULL) { shm_insert(path_from, fnv_from, fd_to); path_from = NULL; shm_drop(fd_to); KASSERT(fd_to->shm_refs > 0, ("Expected >0 refs; got: %d\n", fd_to->shm_refs)); } out_locked: sx_xunlock(&shm_dict_lock); out: free(path_from, M_SHMFD); free(path_to, M_SHMFD); return (error); } static int shm_mmap_large(struct shmfd *shmfd, vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, vm_prot_t max_prot, int flags, vm_ooffset_t foff, struct thread *td) { struct vmspace *vms; vm_map_entry_t next_entry, prev_entry; vm_offset_t align, mask, maxaddr; int docow, error, rv, try; bool curmap; if (shmfd->shm_lp_psind == 0) return (EINVAL); /* MAP_PRIVATE is disabled */ if ((flags & ~(MAP_SHARED | MAP_FIXED | MAP_EXCL | MAP_NOCORE | #ifdef MAP_32BIT MAP_32BIT | #endif MAP_ALIGNMENT_MASK)) != 0) return (EINVAL); vms = td->td_proc->p_vmspace; curmap = map == &vms->vm_map; if (curmap) { error = kern_mmap_racct_check(td, map, size); if (error != 0) return (error); } docow = shmfd->shm_lp_psind << MAP_SPLIT_BOUNDARY_SHIFT; docow |= MAP_INHERIT_SHARE; if ((flags & MAP_NOCORE) != 0) docow |= MAP_DISABLE_COREDUMP; mask = pagesizes[shmfd->shm_lp_psind] - 1; if ((foff & mask) != 0) return (EINVAL); maxaddr = vm_map_max(map); #ifdef MAP_32BIT if ((flags & MAP_32BIT) != 0 && maxaddr > MAP_32BIT_MAX_ADDR) maxaddr = MAP_32BIT_MAX_ADDR; #endif if (size == 0 || (size & mask) != 0 || (*addr != 0 && ((*addr & mask) != 0 || *addr + size < *addr || *addr + size > maxaddr))) return (EINVAL); align = flags & MAP_ALIGNMENT_MASK; if (align == 0) { align = pagesizes[shmfd->shm_lp_psind]; } else if (align == MAP_ALIGNED_SUPER) { if (shmfd->shm_lp_psind != 1) return (EINVAL); align = pagesizes[1]; } else { align >>= MAP_ALIGNMENT_SHIFT; align = 1ULL << align; /* Also handles overflow. */ if (align < pagesizes[shmfd->shm_lp_psind]) return (EINVAL); } vm_map_lock(map); if ((flags & MAP_FIXED) == 0) { try = 1; if (curmap && (*addr == 0 || (*addr >= round_page((vm_offset_t)vms->vm_taddr) && *addr < round_page((vm_offset_t)vms->vm_daddr + lim_max(td, RLIMIT_DATA))))) { *addr = roundup2((vm_offset_t)vms->vm_daddr + lim_max(td, RLIMIT_DATA), pagesizes[shmfd->shm_lp_psind]); } again: rv = vm_map_find_aligned(map, addr, size, maxaddr, align); if (rv != KERN_SUCCESS) { if (try == 1) { try = 2; *addr = vm_map_min(map); if ((*addr & mask) != 0) *addr = (*addr + mask) & mask; goto again; } goto fail1; } } else if ((flags & MAP_EXCL) == 0) { rv = vm_map_delete(map, *addr, *addr + size); if (rv != KERN_SUCCESS) goto fail1; } else { error = ENOSPC; if (vm_map_lookup_entry(map, *addr, &prev_entry)) goto fail; next_entry = vm_map_entry_succ(prev_entry); if (next_entry->start < *addr + size) goto fail; } rv = vm_map_insert(map, shmfd->shm_object, foff, *addr, *addr + size, prot, max_prot, docow); fail1: error = vm_mmap_to_errno(rv); fail: vm_map_unlock(map); return (error); } static int shm_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t objsize, vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff, struct thread *td) { struct shmfd *shmfd; vm_prot_t maxprot; int error; bool writecnt; void *rl_cookie; shmfd = fp->f_data; maxprot = VM_PROT_NONE; rl_cookie = rangelock_rlock(&shmfd->shm_rl, 0, objsize, &shmfd->shm_mtx); /* FREAD should always be set. */ if ((fp->f_flag & FREAD) != 0) maxprot |= VM_PROT_EXECUTE | VM_PROT_READ; /* * If FWRITE's set, we can allow VM_PROT_WRITE unless it's a shared * mapping with a write seal applied. Private mappings are always * writeable. */ if ((flags & MAP_SHARED) == 0) { cap_maxprot |= VM_PROT_WRITE; maxprot |= VM_PROT_WRITE; writecnt = false; } else { if ((fp->f_flag & FWRITE) != 0 && (shmfd->shm_seals & F_SEAL_WRITE) == 0) maxprot |= VM_PROT_WRITE; /* * Any mappings from a writable descriptor may be upgraded to * VM_PROT_WRITE with mprotect(2), unless a write-seal was * applied between the open and subsequent mmap(2). We want to * reject application of a write seal as long as any such * mapping exists so that the seal cannot be trivially bypassed. */ writecnt = (maxprot & VM_PROT_WRITE) != 0; if (!writecnt && (prot & VM_PROT_WRITE) != 0) { error = EACCES; goto out; } } maxprot &= cap_maxprot; /* See comment in vn_mmap(). */ if ( #ifdef _LP64 objsize > OFF_MAX || #endif foff > OFF_MAX - objsize) { error = EINVAL; goto out; } #ifdef MAC error = mac_posixshm_check_mmap(td->td_ucred, shmfd, prot, flags); if (error != 0) goto out; #endif mtx_lock(&shm_timestamp_lock); vfs_timestamp(&shmfd->shm_atime); mtx_unlock(&shm_timestamp_lock); vm_object_reference(shmfd->shm_object); if (shm_largepage(shmfd)) { writecnt = false; error = shm_mmap_large(shmfd, map, addr, objsize, prot, maxprot, flags, foff, td); } else { if (writecnt) { vm_pager_update_writecount(shmfd->shm_object, 0, objsize); } error = vm_mmap_object(map, addr, objsize, prot, maxprot, flags, shmfd->shm_object, foff, writecnt, td); } if (error != 0) { if (writecnt) vm_pager_release_writecount(shmfd->shm_object, 0, objsize); vm_object_deallocate(shmfd->shm_object); } out: rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (error); } static int shm_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; int error; error = 0; shmfd = fp->f_data; mtx_lock(&shm_timestamp_lock); /* * SUSv4 says that x bits of permission need not be affected. * Be consistent with our shm_open there. */ #ifdef MAC error = mac_posixshm_check_setmode(active_cred, shmfd, mode); if (error != 0) goto out; #endif error = vaccess(VREG, shmfd->shm_mode, shmfd->shm_uid, shmfd->shm_gid, VADMIN, active_cred); if (error != 0) goto out; shmfd->shm_mode = mode & ACCESSPERMS; out: mtx_unlock(&shm_timestamp_lock); return (error); } static int shm_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, struct thread *td) { struct shmfd *shmfd; int error; error = 0; shmfd = fp->f_data; mtx_lock(&shm_timestamp_lock); #ifdef MAC error = mac_posixshm_check_setowner(active_cred, shmfd, uid, gid); if (error != 0) goto out; #endif if (uid == (uid_t)-1) uid = shmfd->shm_uid; if (gid == (gid_t)-1) gid = shmfd->shm_gid; if (((uid != shmfd->shm_uid && uid != active_cred->cr_uid) || (gid != shmfd->shm_gid && !groupmember(gid, active_cred))) && (error = priv_check_cred(active_cred, PRIV_VFS_CHOWN))) goto out; shmfd->shm_uid = uid; shmfd->shm_gid = gid; out: mtx_unlock(&shm_timestamp_lock); return (error); } /* * Helper routines to allow the backing object of a shared memory file * descriptor to be mapped in the kernel. */ int shm_map(struct file *fp, size_t size, off_t offset, void **memp) { struct shmfd *shmfd; vm_offset_t kva, ofs; vm_object_t obj; int rv; if (fp->f_type != DTYPE_SHM) return (EINVAL); shmfd = fp->f_data; obj = shmfd->shm_object; VM_OBJECT_WLOCK(obj); /* * XXXRW: This validation is probably insufficient, and subject to * sign errors. It should be fixed. */ if (offset >= shmfd->shm_size || offset + size > round_page(shmfd->shm_size)) { VM_OBJECT_WUNLOCK(obj); return (EINVAL); } shmfd->shm_kmappings++; vm_object_reference_locked(obj); VM_OBJECT_WUNLOCK(obj); /* Map the object into the kernel_map and wire it. */ kva = vm_map_min(kernel_map); ofs = offset & PAGE_MASK; offset = trunc_page(offset); size = round_page(size + ofs); rv = vm_map_find(kernel_map, obj, offset, &kva, size, 0, VMFS_OPTIMAL_SPACE, VM_PROT_READ | VM_PROT_WRITE, VM_PROT_READ | VM_PROT_WRITE, 0); if (rv == KERN_SUCCESS) { rv = vm_map_wire(kernel_map, kva, kva + size, VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES); if (rv == KERN_SUCCESS) { *memp = (void *)(kva + ofs); return (0); } vm_map_remove(kernel_map, kva, kva + size); } else vm_object_deallocate(obj); /* On failure, drop our mapping reference. */ VM_OBJECT_WLOCK(obj); shmfd->shm_kmappings--; VM_OBJECT_WUNLOCK(obj); return (vm_mmap_to_errno(rv)); } /* * We require the caller to unmap the entire entry. This allows us to * safely decrement shm_kmappings when a mapping is removed. */ int shm_unmap(struct file *fp, void *mem, size_t size) { struct shmfd *shmfd; vm_map_entry_t entry; vm_offset_t kva, ofs; vm_object_t obj; vm_pindex_t pindex; vm_prot_t prot; boolean_t wired; vm_map_t map; int rv; if (fp->f_type != DTYPE_SHM) return (EINVAL); shmfd = fp->f_data; kva = (vm_offset_t)mem; ofs = kva & PAGE_MASK; kva = trunc_page(kva); size = round_page(size + ofs); map = kernel_map; rv = vm_map_lookup(&map, kva, VM_PROT_READ | VM_PROT_WRITE, &entry, &obj, &pindex, &prot, &wired); if (rv != KERN_SUCCESS) return (EINVAL); if (entry->start != kva || entry->end != kva + size) { vm_map_lookup_done(map, entry); return (EINVAL); } vm_map_lookup_done(map, entry); if (obj != shmfd->shm_object) return (EINVAL); vm_map_remove(map, kva, kva + size); VM_OBJECT_WLOCK(obj); KASSERT(shmfd->shm_kmappings > 0, ("shm_unmap: object not mapped")); shmfd->shm_kmappings--; VM_OBJECT_WUNLOCK(obj); return (0); } static int shm_fill_kinfo_locked(struct shmfd *shmfd, struct kinfo_file *kif, bool list) { const char *path, *pr_path; size_t pr_pathlen; bool visible; sx_assert(&shm_dict_lock, SA_LOCKED); kif->kf_type = KF_TYPE_SHM; kif->kf_un.kf_file.kf_file_mode = S_IFREG | shmfd->shm_mode; kif->kf_un.kf_file.kf_file_size = shmfd->shm_size; if (shmfd->shm_path != NULL) { if (shmfd->shm_path != NULL) { path = shmfd->shm_path; pr_path = curthread->td_ucred->cr_prison->pr_path; if (strcmp(pr_path, "/") != 0) { /* Return the jail-rooted pathname. */ pr_pathlen = strlen(pr_path); visible = strncmp(path, pr_path, pr_pathlen) == 0 && path[pr_pathlen] == '/'; if (list && !visible) return (EPERM); if (visible) path += pr_pathlen; } strlcpy(kif->kf_path, path, sizeof(kif->kf_path)); } } return (0); } static int shm_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp __unused) { int res; sx_slock(&shm_dict_lock); res = shm_fill_kinfo_locked(fp->f_data, kif, false); sx_sunlock(&shm_dict_lock); return (res); } static int shm_add_seals(struct file *fp, int seals) { struct shmfd *shmfd; void *rl_cookie; vm_ooffset_t writemappings; int error, nseals; error = 0; shmfd = fp->f_data; rl_cookie = rangelock_wlock(&shmfd->shm_rl, 0, OFF_MAX, &shmfd->shm_mtx); /* Even already-set seals should result in EPERM. */ if ((shmfd->shm_seals & F_SEAL_SEAL) != 0) { error = EPERM; goto out; } nseals = seals & ~shmfd->shm_seals; if ((nseals & F_SEAL_WRITE) != 0) { if (shm_largepage(shmfd)) { error = ENOTSUP; goto out; } /* * The rangelock above prevents writable mappings from being * added after we've started applying seals. The RLOCK here * is to avoid torn reads on ILP32 arches as unmapping/reducing * writemappings will be done without a rangelock. */ VM_OBJECT_RLOCK(shmfd->shm_object); writemappings = shmfd->shm_object->un_pager.swp.writemappings; VM_OBJECT_RUNLOCK(shmfd->shm_object); /* kmappings are also writable */ if (writemappings > 0) { error = EBUSY; goto out; } } shmfd->shm_seals |= nseals; out: rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (error); } static int shm_get_seals(struct file *fp, int *seals) { struct shmfd *shmfd; shmfd = fp->f_data; *seals = shmfd->shm_seals; return (0); } static int shm_deallocate(struct shmfd *shmfd, off_t *offset, off_t *length, int flags) { vm_object_t object; vm_pindex_t pistart, pi, piend; vm_ooffset_t off, len; int startofs, endofs, end; int error; off = *offset; len = *length; KASSERT(off + len <= (vm_ooffset_t)OFF_MAX, ("off + len overflows")); if (off + len > shmfd->shm_size) len = shmfd->shm_size - off; object = shmfd->shm_object; startofs = off & PAGE_MASK; endofs = (off + len) & PAGE_MASK; pistart = OFF_TO_IDX(off); piend = OFF_TO_IDX(off + len); pi = OFF_TO_IDX(off + PAGE_MASK); error = 0; /* Handle the case when offset is on or beyond shm size. */ if ((off_t)len <= 0) { - *offset = shmfd->shm_size; *length = 0; return (0); } VM_OBJECT_WLOCK(object); if (startofs != 0) { end = pistart != piend ? PAGE_SIZE : endofs; error = shm_partial_page_invalidate(object, pistart, startofs, end); if (error) goto out; off += end - startofs; len -= end - startofs; } if (pi < piend) { vm_object_page_remove(object, pi, piend, 0); off += IDX_TO_OFF(piend - pi); len -= IDX_TO_OFF(piend - pi); } if (endofs != 0 && pistart != piend) { error = shm_partial_page_invalidate(object, piend, 0, endofs); if (error) goto out; off += endofs; len -= endofs; } out: VM_OBJECT_WUNLOCK(shmfd->shm_object); *offset = off; *length = len; return (error); } static int shm_fspacectl(struct file *fp, int cmd, off_t *offset, off_t *length, int flags, struct ucred *active_cred, struct thread *td) { void *rl_cookie; struct shmfd *shmfd; off_t off, len; int error; /* This assumes that the caller already checked for overflow. */ error = EINVAL; shmfd = fp->f_data; off = *offset; len = *length; if (cmd != SPACECTL_DEALLOC || off < 0 || len <= 0 || len > OFF_MAX - off || flags != 0) return (EINVAL); rl_cookie = rangelock_wlock(&shmfd->shm_rl, off, off + len, &shmfd->shm_mtx); switch (cmd) { case SPACECTL_DEALLOC: if ((shmfd->shm_seals & F_SEAL_WRITE) != 0) { error = EPERM; break; } error = shm_deallocate(shmfd, &off, &len, flags); *offset = off; *length = len; break; default: __assert_unreachable(); } rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); return (error); } static int shm_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td) { void *rl_cookie; struct shmfd *shmfd; size_t size; int error; /* This assumes that the caller already checked for overflow. */ error = 0; shmfd = fp->f_data; size = offset + len; /* * Just grab the rangelock for the range that we may be attempting to * grow, rather than blocking read/write for regions we won't be * touching while this (potential) resize is in progress. Other * attempts to resize the shmfd will have to take a write lock from 0 to * OFF_MAX, so this being potentially beyond the current usable range of * the shmfd is not necessarily a concern. If other mechanisms are * added to grow a shmfd, this may need to be re-evaluated. */ rl_cookie = rangelock_wlock(&shmfd->shm_rl, offset, size, &shmfd->shm_mtx); if (size > shmfd->shm_size) error = shm_dotruncate_cookie(shmfd, size, rl_cookie); rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx); /* Translate to posix_fallocate(2) return value as needed. */ if (error == ENOMEM) error = ENOSPC; return (error); } static int sysctl_posix_shm_list(SYSCTL_HANDLER_ARGS) { struct shm_mapping *shmm; struct sbuf sb; struct kinfo_file kif; u_long i; ssize_t curlen; int error, error2; sbuf_new_for_sysctl(&sb, NULL, sizeof(struct kinfo_file) * 5, req); sbuf_clear_flags(&sb, SBUF_INCLUDENUL); curlen = 0; error = 0; sx_slock(&shm_dict_lock); for (i = 0; i < shm_hash + 1; i++) { LIST_FOREACH(shmm, &shm_dictionary[i], sm_link) { error = shm_fill_kinfo_locked(shmm->sm_shmfd, &kif, true); if (error == EPERM) continue; if (error != 0) break; pack_kinfo(&kif); if (req->oldptr != NULL && kif.kf_structsize + curlen > req->oldlen) break; error = sbuf_bcat(&sb, &kif, kif.kf_structsize) == 0 ? 0 : ENOMEM; if (error != 0) break; curlen += kif.kf_structsize; } } sx_sunlock(&shm_dict_lock); error2 = sbuf_finish(&sb); sbuf_delete(&sb); return (error != 0 ? error : error2); } SYSCTL_PROC(_kern_ipc, OID_AUTO, posix_shm_list, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLTYPE_OPAQUE, NULL, 0, sysctl_posix_shm_list, "", "POSIX SHM list"); int kern_shm_open(struct thread *td, const char *path, int flags, mode_t mode, struct filecaps *caps) { return (kern_shm_open2(td, path, flags, mode, 0, caps, NULL)); } /* * This version of the shm_open() interface leaves CLOEXEC behavior up to the * caller, and libc will enforce it for the traditional shm_open() call. This * allows other consumers, like memfd_create(), to opt-in for CLOEXEC. This * interface also includes a 'name' argument that is currently unused, but could * potentially be exported later via some interface for debugging purposes. * From the kernel's perspective, it is optional. Individual consumers like * memfd_create() may require it in order to be compatible with other systems * implementing the same function. */ int sys_shm_open2(struct thread *td, struct shm_open2_args *uap) { return (kern_shm_open2(td, uap->path, uap->flags, uap->mode, uap->shmflags, NULL, uap->name)); } diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c index d5df9cd8bf7b..9fd43004b8fd 100644 --- a/sys/kern/vfs_default.c +++ b/sys/kern/vfs_default.c @@ -1,1756 +1,1755 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed * to Berkeley by John Heidemann of the UCLA Ficus project. * * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static int vop_nolookup(struct vop_lookup_args *); static int vop_norename(struct vop_rename_args *); static int vop_nostrategy(struct vop_strategy_args *); static int get_next_dirent(struct vnode *vp, struct dirent **dpp, char *dirbuf, int dirbuflen, off_t *off, char **cpos, int *len, int *eofflag, struct thread *td); static int dirent_exists(struct vnode *vp, const char *dirname, struct thread *td); #define DIRENT_MINSIZE (sizeof(struct dirent) - (MAXNAMLEN+1) + 4) static int vop_stdis_text(struct vop_is_text_args *ap); static int vop_stdunset_text(struct vop_unset_text_args *ap); static int vop_stdadd_writecount(struct vop_add_writecount_args *ap); static int vop_stdcopy_file_range(struct vop_copy_file_range_args *ap); static int vop_stdfdatasync(struct vop_fdatasync_args *ap); static int vop_stdgetpages_async(struct vop_getpages_async_args *ap); static int vop_stdread_pgcache(struct vop_read_pgcache_args *ap); static int vop_stdstat(struct vop_stat_args *ap); static int vop_stdvput_pair(struct vop_vput_pair_args *ap); static int vop_stddeallocate(struct vop_deallocate_args *ap); /* * This vnode table stores what we want to do if the filesystem doesn't * implement a particular VOP. * * If there is no specific entry here, we will return EOPNOTSUPP. * * Note that every filesystem has to implement either vop_access * or vop_accessx; failing to do so will result in immediate crash * due to stack overflow, as vop_stdaccess() calls vop_stdaccessx(), * which calls vop_stdaccess() etc. */ struct vop_vector default_vnodeops = { .vop_default = NULL, .vop_bypass = VOP_EOPNOTSUPP, .vop_access = vop_stdaccess, .vop_accessx = vop_stdaccessx, .vop_advise = vop_stdadvise, .vop_advlock = vop_stdadvlock, .vop_advlockasync = vop_stdadvlockasync, .vop_advlockpurge = vop_stdadvlockpurge, .vop_allocate = vop_stdallocate, .vop_deallocate = vop_stddeallocate, .vop_bmap = vop_stdbmap, .vop_close = VOP_NULL, .vop_fsync = VOP_NULL, .vop_stat = vop_stdstat, .vop_fdatasync = vop_stdfdatasync, .vop_getpages = vop_stdgetpages, .vop_getpages_async = vop_stdgetpages_async, .vop_getwritemount = vop_stdgetwritemount, .vop_inactive = VOP_NULL, .vop_need_inactive = vop_stdneed_inactive, .vop_ioctl = vop_stdioctl, .vop_kqfilter = vop_stdkqfilter, .vop_islocked = vop_stdislocked, .vop_lock1 = vop_stdlock, .vop_lookup = vop_nolookup, .vop_open = VOP_NULL, .vop_pathconf = VOP_EINVAL, .vop_poll = vop_nopoll, .vop_putpages = vop_stdputpages, .vop_readlink = VOP_EINVAL, .vop_read_pgcache = vop_stdread_pgcache, .vop_rename = vop_norename, .vop_revoke = VOP_PANIC, .vop_strategy = vop_nostrategy, .vop_unlock = vop_stdunlock, .vop_vptocnp = vop_stdvptocnp, .vop_vptofh = vop_stdvptofh, .vop_unp_bind = vop_stdunp_bind, .vop_unp_connect = vop_stdunp_connect, .vop_unp_detach = vop_stdunp_detach, .vop_is_text = vop_stdis_text, .vop_set_text = vop_stdset_text, .vop_unset_text = vop_stdunset_text, .vop_add_writecount = vop_stdadd_writecount, .vop_copy_file_range = vop_stdcopy_file_range, .vop_vput_pair = vop_stdvput_pair, }; VFS_VOP_VECTOR_REGISTER(default_vnodeops); /* * Series of placeholder functions for various error returns for * VOPs. */ int vop_eopnotsupp(struct vop_generic_args *ap) { /* printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name); */ return (EOPNOTSUPP); } int vop_ebadf(struct vop_generic_args *ap) { return (EBADF); } int vop_enotty(struct vop_generic_args *ap) { return (ENOTTY); } int vop_einval(struct vop_generic_args *ap) { return (EINVAL); } int vop_enoent(struct vop_generic_args *ap) { return (ENOENT); } int vop_eagain(struct vop_generic_args *ap) { return (EAGAIN); } int vop_null(struct vop_generic_args *ap) { return (0); } /* * Helper function to panic on some bad VOPs in some filesystems. */ int vop_panic(struct vop_generic_args *ap) { panic("filesystem goof: vop_panic[%s]", ap->a_desc->vdesc_name); } /* * vop_std and vop_no are default functions for use by * filesystems that need the "default reasonable" implementation for a * particular operation. * * The documentation for the operations they implement exists (if it exists) * in the VOP_(9) manpage (all uppercase). */ /* * Default vop for filesystems that do not support name lookup */ static int vop_nolookup(ap) struct vop_lookup_args /* { struct vnode *a_dvp; struct vnode **a_vpp; struct componentname *a_cnp; } */ *ap; { *ap->a_vpp = NULL; return (ENOTDIR); } /* * vop_norename: * * Handle unlock and reference counting for arguments of vop_rename * for filesystems that do not implement rename operation. */ static int vop_norename(struct vop_rename_args *ap) { vop_rename_fail(ap); return (EOPNOTSUPP); } /* * vop_nostrategy: * * Strategy routine for VFS devices that have none. * * BIO_ERROR and B_INVAL must be cleared prior to calling any strategy * routine. Typically this is done for a BIO_READ strategy call. * Typically B_INVAL is assumed to already be clear prior to a write * and should not be cleared manually unless you just made the buffer * invalid. BIO_ERROR should be cleared either way. */ static int vop_nostrategy (struct vop_strategy_args *ap) { printf("No strategy for buffer at %p\n", ap->a_bp); vn_printf(ap->a_vp, "vnode "); ap->a_bp->b_ioflags |= BIO_ERROR; ap->a_bp->b_error = EOPNOTSUPP; bufdone(ap->a_bp); return (EOPNOTSUPP); } static int get_next_dirent(struct vnode *vp, struct dirent **dpp, char *dirbuf, int dirbuflen, off_t *off, char **cpos, int *len, int *eofflag, struct thread *td) { int error, reclen; struct uio uio; struct iovec iov; struct dirent *dp; KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp)); KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp)); if (*len == 0) { iov.iov_base = dirbuf; iov.iov_len = dirbuflen; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = *off; uio.uio_resid = dirbuflen; uio.uio_segflg = UIO_SYSSPACE; uio.uio_rw = UIO_READ; uio.uio_td = td; *eofflag = 0; #ifdef MAC error = mac_vnode_check_readdir(td->td_ucred, vp); if (error == 0) #endif error = VOP_READDIR(vp, &uio, td->td_ucred, eofflag, NULL, NULL); if (error) return (error); *off = uio.uio_offset; *cpos = dirbuf; *len = (dirbuflen - uio.uio_resid); if (*len == 0) return (ENOENT); } dp = (struct dirent *)(*cpos); reclen = dp->d_reclen; *dpp = dp; /* check for malformed directory.. */ if (reclen < DIRENT_MINSIZE) return (EINVAL); *cpos += reclen; *len -= reclen; return (0); } /* * Check if a named file exists in a given directory vnode. */ static int dirent_exists(struct vnode *vp, const char *dirname, struct thread *td) { char *dirbuf, *cpos; int error, eofflag, dirbuflen, len, found; off_t off; struct dirent *dp; struct vattr va; KASSERT(VOP_ISLOCKED(vp), ("vp %p is not locked", vp)); KASSERT(vp->v_type == VDIR, ("vp %p is not a directory", vp)); found = 0; error = VOP_GETATTR(vp, &va, td->td_ucred); if (error) return (found); dirbuflen = DEV_BSIZE; if (dirbuflen < va.va_blocksize) dirbuflen = va.va_blocksize; dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK); off = 0; len = 0; do { error = get_next_dirent(vp, &dp, dirbuf, dirbuflen, &off, &cpos, &len, &eofflag, td); if (error) goto out; if (dp->d_type != DT_WHT && dp->d_fileno != 0 && strcmp(dp->d_name, dirname) == 0) { found = 1; goto out; } } while (len > 0 || !eofflag); out: free(dirbuf, M_TEMP); return (found); } int vop_stdaccess(struct vop_access_args *ap) { KASSERT((ap->a_accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, ("invalid bit in accmode")); return (VOP_ACCESSX(ap->a_vp, ap->a_accmode, ap->a_cred, ap->a_td)); } int vop_stdaccessx(struct vop_accessx_args *ap) { int error; accmode_t accmode = ap->a_accmode; error = vfs_unixify_accmode(&accmode); if (error != 0) return (error); if (accmode == 0) return (0); return (VOP_ACCESS(ap->a_vp, accmode, ap->a_cred, ap->a_td)); } /* * Advisory record locking support */ int vop_stdadvlock(struct vop_advlock_args *ap) { struct vnode *vp; struct mount *mp; struct vattr vattr; int error; vp = ap->a_vp; /* * Provide atomicity of open(O_CREAT | O_EXCL | O_EXLOCK) for * local filesystems. See vn_open_cred() for reciprocal part. */ mp = vp->v_mount; if (mp != NULL && (mp->mnt_flag & MNT_LOCAL) != 0 && ap->a_op == F_SETLK && (ap->a_flags & F_FIRSTOPEN) == 0) { VI_LOCK(vp); while ((vp->v_iflag & VI_FOPENING) != 0) msleep(vp, VI_MTX(vp), PLOCK, "lockfo", 0); VI_UNLOCK(vp); } if (ap->a_fl->l_whence == SEEK_END) { /* * The NFSv4 server must avoid doing a vn_lock() here, since it * can deadlock the nfsd threads, due to a LOR. Fortunately * the NFSv4 server always uses SEEK_SET and this code is * only required for the SEEK_END case. */ vn_lock(vp, LK_SHARED | LK_RETRY); error = VOP_GETATTR(vp, &vattr, curthread->td_ucred); VOP_UNLOCK(vp); if (error) return (error); } else vattr.va_size = 0; return (lf_advlock(ap, &(vp->v_lockf), vattr.va_size)); } int vop_stdadvlockasync(struct vop_advlockasync_args *ap) { struct vnode *vp; struct vattr vattr; int error; vp = ap->a_vp; if (ap->a_fl->l_whence == SEEK_END) { /* The size argument is only needed for SEEK_END. */ vn_lock(vp, LK_SHARED | LK_RETRY); error = VOP_GETATTR(vp, &vattr, curthread->td_ucred); VOP_UNLOCK(vp); if (error) return (error); } else vattr.va_size = 0; return (lf_advlockasync(ap, &(vp->v_lockf), vattr.va_size)); } int vop_stdadvlockpurge(struct vop_advlockpurge_args *ap) { struct vnode *vp; vp = ap->a_vp; lf_purgelocks(vp, &vp->v_lockf); return (0); } /* * vop_stdpathconf: * * Standard implementation of POSIX pathconf, to get information about limits * for a filesystem. * Override per filesystem for the case where the filesystem has smaller * limits. */ int vop_stdpathconf(ap) struct vop_pathconf_args /* { struct vnode *a_vp; int a_name; int *a_retval; } */ *ap; { switch (ap->a_name) { case _PC_ASYNC_IO: *ap->a_retval = _POSIX_ASYNCHRONOUS_IO; return (0); case _PC_PATH_MAX: *ap->a_retval = PATH_MAX; return (0); case _PC_ACL_EXTENDED: case _PC_ACL_NFS4: case _PC_CAP_PRESENT: case _PC_DEALLOC_PRESENT: case _PC_INF_PRESENT: case _PC_MAC_PRESENT: *ap->a_retval = 0; return (0); default: return (EINVAL); } /* NOTREACHED */ } /* * Standard lock, unlock and islocked functions. */ int vop_stdlock(ap) struct vop_lock1_args /* { struct vnode *a_vp; int a_flags; char *file; int line; } */ *ap; { struct vnode *vp = ap->a_vp; struct mtx *ilk; ilk = VI_MTX(vp); return (lockmgr_lock_flags(vp->v_vnlock, ap->a_flags, &ilk->lock_object, ap->a_file, ap->a_line)); } /* See above. */ int vop_stdunlock(ap) struct vop_unlock_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; return (lockmgr_unlock(vp->v_vnlock)); } /* See above. */ int vop_stdislocked(ap) struct vop_islocked_args /* { struct vnode *a_vp; } */ *ap; { return (lockstatus(ap->a_vp->v_vnlock)); } /* * Variants of the above set. * * Differences are: * - shared locking disablement is not supported * - v_vnlock pointer is not honored */ int vop_lock(ap) struct vop_lock1_args /* { struct vnode *a_vp; int a_flags; char *file; int line; } */ *ap; { struct vnode *vp = ap->a_vp; int flags = ap->a_flags; struct mtx *ilk; MPASS(vp->v_vnlock == &vp->v_lock); if (__predict_false((flags & ~(LK_TYPE_MASK | LK_NODDLKTREAT | LK_RETRY)) != 0)) goto other; switch (flags & LK_TYPE_MASK) { case LK_SHARED: return (lockmgr_slock(&vp->v_lock, flags, ap->a_file, ap->a_line)); case LK_EXCLUSIVE: return (lockmgr_xlock(&vp->v_lock, flags, ap->a_file, ap->a_line)); } other: ilk = VI_MTX(vp); return (lockmgr_lock_flags(&vp->v_lock, flags, &ilk->lock_object, ap->a_file, ap->a_line)); } int vop_unlock(ap) struct vop_unlock_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; MPASS(vp->v_vnlock == &vp->v_lock); return (lockmgr_unlock(&vp->v_lock)); } int vop_islocked(ap) struct vop_islocked_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; MPASS(vp->v_vnlock == &vp->v_lock); return (lockstatus(&vp->v_lock)); } /* * Return true for select/poll. */ int vop_nopoll(ap) struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct ucred *a_cred; struct thread *a_td; } */ *ap; { if (ap->a_events & ~POLLSTANDARD) return (POLLNVAL); return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); } /* * Implement poll for local filesystems that support it. */ int vop_stdpoll(ap) struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct ucred *a_cred; struct thread *a_td; } */ *ap; { if (ap->a_events & ~POLLSTANDARD) return (vn_pollrecord(ap->a_vp, ap->a_td, ap->a_events)); return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); } /* * Return our mount point, as we will take charge of the writes. */ int vop_stdgetwritemount(ap) struct vop_getwritemount_args /* { struct vnode *a_vp; struct mount **a_mpp; } */ *ap; { struct mount *mp; struct vnode *vp; /* * Note that having a reference does not prevent forced unmount from * setting ->v_mount to NULL after the lock gets released. This is of * no consequence for typical consumers (most notably vn_start_write) * since in this case the vnode is VIRF_DOOMED. Unmount might have * progressed far enough that its completion is only delayed by the * reference obtained here. The consumer only needs to concern itself * with releasing it. */ vp = ap->a_vp; mp = vfs_ref_from_vp(vp); *(ap->a_mpp) = mp; return (0); } /* * If the file system doesn't implement VOP_BMAP, then return sensible defaults: * - Return the vnode's bufobj instead of any underlying device's bufobj * - Calculate the physical block number as if there were equal size * consecutive blocks, but * - Report no contiguous runs of blocks. */ int vop_stdbmap(ap) struct vop_bmap_args /* { struct vnode *a_vp; daddr_t a_bn; struct bufobj **a_bop; daddr_t *a_bnp; int *a_runp; int *a_runb; } */ *ap; { if (ap->a_bop != NULL) *ap->a_bop = &ap->a_vp->v_bufobj; if (ap->a_bnp != NULL) *ap->a_bnp = ap->a_bn * btodb(ap->a_vp->v_mount->mnt_stat.f_iosize); if (ap->a_runp != NULL) *ap->a_runp = 0; if (ap->a_runb != NULL) *ap->a_runb = 0; return (0); } int vop_stdfsync(ap) struct vop_fsync_args /* { struct vnode *a_vp; int a_waitfor; struct thread *a_td; } */ *ap; { return (vn_fsync_buf(ap->a_vp, ap->a_waitfor)); } static int vop_stdfdatasync(struct vop_fdatasync_args *ap) { return (VOP_FSYNC(ap->a_vp, MNT_WAIT, ap->a_td)); } int vop_stdfdatasync_buf(struct vop_fdatasync_args *ap) { return (vn_fsync_buf(ap->a_vp, MNT_WAIT)); } /* XXX Needs good comment and more info in the manpage (VOP_GETPAGES(9)). */ int vop_stdgetpages(ap) struct vop_getpages_args /* { struct vnode *a_vp; vm_page_t *a_m; int a_count; int *a_rbehind; int *a_rahead; } */ *ap; { return vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count, ap->a_rbehind, ap->a_rahead, NULL, NULL); } static int vop_stdgetpages_async(struct vop_getpages_async_args *ap) { int error; error = VOP_GETPAGES(ap->a_vp, ap->a_m, ap->a_count, ap->a_rbehind, ap->a_rahead); if (ap->a_iodone != NULL) ap->a_iodone(ap->a_arg, ap->a_m, ap->a_count, error); return (error); } int vop_stdkqfilter(struct vop_kqfilter_args *ap) { return vfs_kqfilter(ap); } /* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */ int vop_stdputpages(ap) struct vop_putpages_args /* { struct vnode *a_vp; vm_page_t *a_m; int a_count; int a_sync; int *a_rtvals; } */ *ap; { return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count, ap->a_sync, ap->a_rtvals); } int vop_stdvptofh(struct vop_vptofh_args *ap) { return (EOPNOTSUPP); } int vop_stdvptocnp(struct vop_vptocnp_args *ap) { struct vnode *vp = ap->a_vp; struct vnode **dvp = ap->a_vpp; struct ucred *cred; char *buf = ap->a_buf; size_t *buflen = ap->a_buflen; char *dirbuf, *cpos; int i, error, eofflag, dirbuflen, flags, locked, len, covered; off_t off; ino_t fileno; struct vattr va; struct nameidata nd; struct thread *td; struct dirent *dp; struct vnode *mvp; i = *buflen; error = 0; covered = 0; td = curthread; cred = td->td_ucred; if (vp->v_type != VDIR) return (ENOENT); error = VOP_GETATTR(vp, &va, cred); if (error) return (error); VREF(vp); locked = VOP_ISLOCKED(vp); VOP_UNLOCK(vp); NDINIT_ATVP(&nd, LOOKUP, FOLLOW | LOCKSHARED | LOCKLEAF, UIO_SYSSPACE, "..", vp, td); flags = FREAD; error = vn_open_cred(&nd, &flags, 0, VN_OPEN_NOAUDIT, cred, NULL); if (error) { vn_lock(vp, locked | LK_RETRY); return (error); } NDFREE(&nd, NDF_ONLY_PNBUF); mvp = *dvp = nd.ni_vp; if (vp->v_mount != (*dvp)->v_mount && ((*dvp)->v_vflag & VV_ROOT) && ((*dvp)->v_mount->mnt_flag & MNT_UNION)) { *dvp = (*dvp)->v_mount->mnt_vnodecovered; VREF(mvp); VOP_UNLOCK(mvp); vn_close(mvp, FREAD, cred, td); VREF(*dvp); vn_lock(*dvp, LK_SHARED | LK_RETRY); covered = 1; } fileno = va.va_fileid; dirbuflen = DEV_BSIZE; if (dirbuflen < va.va_blocksize) dirbuflen = va.va_blocksize; dirbuf = (char *)malloc(dirbuflen, M_TEMP, M_WAITOK); if ((*dvp)->v_type != VDIR) { error = ENOENT; goto out; } off = 0; len = 0; do { /* call VOP_READDIR of parent */ error = get_next_dirent(*dvp, &dp, dirbuf, dirbuflen, &off, &cpos, &len, &eofflag, td); if (error) goto out; if ((dp->d_type != DT_WHT) && (dp->d_fileno == fileno)) { if (covered) { VOP_UNLOCK(*dvp); vn_lock(mvp, LK_SHARED | LK_RETRY); if (dirent_exists(mvp, dp->d_name, td)) { error = ENOENT; VOP_UNLOCK(mvp); vn_lock(*dvp, LK_SHARED | LK_RETRY); goto out; } VOP_UNLOCK(mvp); vn_lock(*dvp, LK_SHARED | LK_RETRY); } i -= dp->d_namlen; if (i < 0) { error = ENOMEM; goto out; } if (dp->d_namlen == 1 && dp->d_name[0] == '.') { error = ENOENT; } else { bcopy(dp->d_name, buf + i, dp->d_namlen); error = 0; } goto out; } } while (len > 0 || !eofflag); error = ENOENT; out: free(dirbuf, M_TEMP); if (!error) { *buflen = i; vref(*dvp); } if (covered) { vput(*dvp); vrele(mvp); } else { VOP_UNLOCK(mvp); vn_close(mvp, FREAD, cred, td); } vn_lock(vp, locked | LK_RETRY); return (error); } int vop_stdallocate(struct vop_allocate_args *ap) { #ifdef __notyet__ struct statfs *sfs; off_t maxfilesize = 0; #endif struct iovec aiov; struct vattr vattr, *vap; struct uio auio; off_t fsize, len, cur, offset; uint8_t *buf; struct thread *td; struct vnode *vp; size_t iosize; int error; buf = NULL; error = 0; td = curthread; vap = &vattr; vp = ap->a_vp; len = *ap->a_len; offset = *ap->a_offset; error = VOP_GETATTR(vp, vap, td->td_ucred); if (error != 0) goto out; fsize = vap->va_size; iosize = vap->va_blocksize; if (iosize == 0) iosize = BLKDEV_IOSIZE; if (iosize > maxphys) iosize = maxphys; buf = malloc(iosize, M_TEMP, M_WAITOK); #ifdef __notyet__ /* * Check if the filesystem sets f_maxfilesize; if not use * VOP_SETATTR to perform the check. */ sfs = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK); error = VFS_STATFS(vp->v_mount, sfs, td); if (error == 0) maxfilesize = sfs->f_maxfilesize; free(sfs, M_STATFS); if (error != 0) goto out; if (maxfilesize) { if (offset > maxfilesize || len > maxfilesize || offset + len > maxfilesize) { error = EFBIG; goto out; } } else #endif if (offset + len > vap->va_size) { /* * Test offset + len against the filesystem's maxfilesize. */ VATTR_NULL(vap); vap->va_size = offset + len; error = VOP_SETATTR(vp, vap, td->td_ucred); if (error != 0) goto out; VATTR_NULL(vap); vap->va_size = fsize; error = VOP_SETATTR(vp, vap, td->td_ucred); if (error != 0) goto out; } for (;;) { /* * Read and write back anything below the nominal file * size. There's currently no way outside the filesystem * to know whether this area is sparse or not. */ cur = iosize; if ((offset % iosize) != 0) cur -= (offset % iosize); if (cur > len) cur = len; if (offset < fsize) { aiov.iov_base = buf; aiov.iov_len = cur; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = offset; auio.uio_resid = cur; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_READ; auio.uio_td = td; error = VOP_READ(vp, &auio, 0, td->td_ucred); if (error != 0) break; if (auio.uio_resid > 0) { bzero(buf + cur - auio.uio_resid, auio.uio_resid); } } else { bzero(buf, cur); } aiov.iov_base = buf; aiov.iov_len = cur; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = offset; auio.uio_resid = cur; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_WRITE; auio.uio_td = td; error = VOP_WRITE(vp, &auio, 0, td->td_ucred); if (error != 0) break; len -= cur; offset += cur; if (len == 0) break; if (should_yield()) break; } out: *ap->a_len = len; *ap->a_offset = offset; free(buf, M_TEMP); return (error); } static int vp_zerofill(struct vnode *vp, struct vattr *vap, off_t *offsetp, off_t *lenp, int ioflag, struct ucred *cred) { int iosize; int error = 0; struct iovec aiov; struct uio auio; struct thread *td; off_t offset, len; iosize = vap->va_blocksize; td = curthread; offset = *offsetp; len = *lenp; if (iosize == 0) iosize = BLKDEV_IOSIZE; /* If va_blocksize is 512 bytes, iosize will be 4 kilobytes */ iosize = min(iosize * 8, ZERO_REGION_SIZE); while (len > 0) { int xfersize = iosize; if (offset % iosize != 0) xfersize -= offset % iosize; if (xfersize > len) xfersize = len; aiov.iov_base = __DECONST(void *, zero_region); aiov.iov_len = xfersize; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_offset = offset; auio.uio_resid = xfersize; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_WRITE; auio.uio_td = td; error = VOP_WRITE(vp, &auio, ioflag, cred); if (error != 0) { len -= xfersize - auio.uio_resid; offset += xfersize - auio.uio_resid; break; } len -= xfersize; offset += xfersize; } *offsetp = offset; *lenp = len; return (error); } static int vop_stddeallocate(struct vop_deallocate_args *ap) { struct vnode *vp; off_t offset, len; struct ucred *cred; int error; struct vattr va; off_t noff, xfersize, rem; vp = ap->a_vp; offset = *ap->a_offset; cred = ap->a_cred; error = VOP_GETATTR(vp, &va, cred); if (error) return (error); len = omin((off_t)va.va_size - offset, *ap->a_len); while (len > 0) { noff = offset; error = vn_bmap_seekhole_locked(vp, FIOSEEKDATA, &noff, cred); if (error) { if (error != ENXIO) /* XXX: Is it okay to fallback further? */ goto out; /* * No more data region to be filled */ + offset += len; len = 0; error = 0; break; } KASSERT(noff >= offset, ("FIOSEEKDATA going backward")); if (noff != offset) { xfersize = omin(noff - offset, len); len -= xfersize; offset += xfersize; if (len == 0) break; } error = vn_bmap_seekhole_locked(vp, FIOSEEKHOLE, &noff, cred); if (error) goto out; /* Fill zeroes */ xfersize = rem = omin(noff - offset, len); error = vp_zerofill(vp, &va, &offset, &rem, ap->a_ioflag, cred); if (error) { len -= xfersize - rem; goto out; } len -= xfersize; if (should_yield()) break; } /* Handle the case when offset is beyond EOF */ - if (len < 0) { - offset += len; + if (len < 0) len = 0; - } out: *ap->a_offset = offset; *ap->a_len = len; return (error); } int vop_stdadvise(struct vop_advise_args *ap) { struct vnode *vp; struct bufobj *bo; daddr_t startn, endn; off_t bstart, bend, start, end; int bsize, error; vp = ap->a_vp; switch (ap->a_advice) { case POSIX_FADV_WILLNEED: /* * Do nothing for now. Filesystems should provide a * custom method which starts an asynchronous read of * the requested region. */ error = 0; break; case POSIX_FADV_DONTNEED: error = 0; vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); if (VN_IS_DOOMED(vp)) { VOP_UNLOCK(vp); break; } /* * Round to block boundaries (and later possibly further to * page boundaries). Applications cannot reasonably be aware * of the boundaries, and the rounding must be to expand at * both extremities to cover enough. It still doesn't cover * read-ahead. For partial blocks, this gives unnecessary * discarding of buffers but is efficient enough since the * pages usually remain in VMIO for some time. */ bsize = vp->v_bufobj.bo_bsize; bstart = rounddown(ap->a_start, bsize); bend = roundup(ap->a_end, bsize); /* * Deactivate pages in the specified range from the backing VM * object. Pages that are resident in the buffer cache will * remain wired until their corresponding buffers are released * below. */ if (vp->v_object != NULL) { start = trunc_page(bstart); end = round_page(bend); VM_OBJECT_RLOCK(vp->v_object); vm_object_page_noreuse(vp->v_object, OFF_TO_IDX(start), OFF_TO_IDX(end)); VM_OBJECT_RUNLOCK(vp->v_object); } bo = &vp->v_bufobj; BO_RLOCK(bo); startn = bstart / bsize; endn = bend / bsize; error = bnoreuselist(&bo->bo_clean, bo, startn, endn); if (error == 0) error = bnoreuselist(&bo->bo_dirty, bo, startn, endn); BO_RUNLOCK(bo); VOP_UNLOCK(vp); break; default: error = EINVAL; break; } return (error); } int vop_stdunp_bind(struct vop_unp_bind_args *ap) { ap->a_vp->v_unpcb = ap->a_unpcb; return (0); } int vop_stdunp_connect(struct vop_unp_connect_args *ap) { *ap->a_unpcb = ap->a_vp->v_unpcb; return (0); } int vop_stdunp_detach(struct vop_unp_detach_args *ap) { ap->a_vp->v_unpcb = NULL; return (0); } static int vop_stdis_text(struct vop_is_text_args *ap) { return (ap->a_vp->v_writecount < 0); } int vop_stdset_text(struct vop_set_text_args *ap) { struct vnode *vp; struct mount *mp; int error, n; vp = ap->a_vp; /* * Avoid the interlock if execs are already present. */ n = atomic_load_int(&vp->v_writecount); for (;;) { if (n > -1) { break; } if (atomic_fcmpset_int(&vp->v_writecount, &n, n - 1)) { return (0); } } VI_LOCK(vp); if (vp->v_writecount > 0) { error = ETXTBSY; } else { /* * If requested by fs, keep a use reference to the * vnode until the last text reference is released. */ mp = vp->v_mount; if (mp != NULL && (mp->mnt_kern_flag & MNTK_TEXT_REFS) != 0 && vp->v_writecount == 0) { VNPASS((vp->v_iflag & VI_TEXT_REF) == 0, vp); vp->v_iflag |= VI_TEXT_REF; vrefl(vp); } atomic_subtract_int(&vp->v_writecount, 1); error = 0; } VI_UNLOCK(vp); return (error); } static int vop_stdunset_text(struct vop_unset_text_args *ap) { struct vnode *vp; int error, n; bool last; vp = ap->a_vp; /* * Avoid the interlock if this is not the last exec. */ n = atomic_load_int(&vp->v_writecount); for (;;) { if (n >= -1) { break; } if (atomic_fcmpset_int(&vp->v_writecount, &n, n + 1)) { return (0); } } last = false; VI_LOCK(vp); if (vp->v_writecount < 0) { if ((vp->v_iflag & VI_TEXT_REF) != 0 && vp->v_writecount == -1) { last = true; vp->v_iflag &= ~VI_TEXT_REF; } atomic_add_int(&vp->v_writecount, 1); error = 0; } else { error = EINVAL; } VI_UNLOCK(vp); if (last) vunref(vp); return (error); } static int vop_stdadd_writecount(struct vop_add_writecount_args *ap) { struct vnode *vp; struct mount *mp; int error; vp = ap->a_vp; VI_LOCK_FLAGS(vp, MTX_DUPOK); if (vp->v_writecount < 0) { error = ETXTBSY; } else { VNASSERT(vp->v_writecount + ap->a_inc >= 0, vp, ("neg writecount increment %d", ap->a_inc)); if (vp->v_writecount == 0) { mp = vp->v_mount; if (mp != NULL && (mp->mnt_kern_flag & MNTK_NOMSYNC) == 0) vlazy(vp); } vp->v_writecount += ap->a_inc; error = 0; } VI_UNLOCK(vp); return (error); } int vop_stdneed_inactive(struct vop_need_inactive_args *ap) { return (1); } int vop_stdioctl(struct vop_ioctl_args *ap) { struct vnode *vp; struct vattr va; off_t *offp; int error; switch (ap->a_command) { case FIOSEEKDATA: case FIOSEEKHOLE: vp = ap->a_vp; error = vn_lock(vp, LK_SHARED); if (error != 0) return (EBADF); if (vp->v_type == VREG) error = VOP_GETATTR(vp, &va, ap->a_cred); else error = ENOTTY; if (error == 0) { offp = ap->a_data; if (*offp < 0 || *offp >= va.va_size) error = ENXIO; else if (ap->a_command == FIOSEEKHOLE) *offp = va.va_size; } VOP_UNLOCK(vp); break; default: error = ENOTTY; break; } return (error); } /* * vfs default ops * used to fill the vfs function table to get reasonable default return values. */ int vfs_stdroot (mp, flags, vpp) struct mount *mp; int flags; struct vnode **vpp; { return (EOPNOTSUPP); } int vfs_stdstatfs (mp, sbp) struct mount *mp; struct statfs *sbp; { return (EOPNOTSUPP); } int vfs_stdquotactl (mp, cmds, uid, arg, mp_busy) struct mount *mp; int cmds; uid_t uid; void *arg; bool *mp_busy; { return (EOPNOTSUPP); } int vfs_stdsync(mp, waitfor) struct mount *mp; int waitfor; { struct vnode *vp, *mvp; struct thread *td; int error, lockreq, allerror = 0; td = curthread; lockreq = LK_EXCLUSIVE | LK_INTERLOCK; if (waitfor != MNT_WAIT) lockreq |= LK_NOWAIT; /* * Force stale buffer cache information to be flushed. */ loop: MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { if (vp->v_bufobj.bo_dirty.bv_cnt == 0) { VI_UNLOCK(vp); continue; } if ((error = vget(vp, lockreq)) != 0) { if (error == ENOENT) { MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); goto loop; } continue; } error = VOP_FSYNC(vp, waitfor, td); if (error) allerror = error; vput(vp); } return (allerror); } int vfs_stdnosync (mp, waitfor) struct mount *mp; int waitfor; { return (0); } static int vop_stdcopy_file_range(struct vop_copy_file_range_args *ap) { int error; error = vn_generic_copy_file_range(ap->a_invp, ap->a_inoffp, ap->a_outvp, ap->a_outoffp, ap->a_lenp, ap->a_flags, ap->a_incred, ap->a_outcred, ap->a_fsizetd); return (error); } int vfs_stdvget (mp, ino, flags, vpp) struct mount *mp; ino_t ino; int flags; struct vnode **vpp; { return (EOPNOTSUPP); } int vfs_stdfhtovp (mp, fhp, flags, vpp) struct mount *mp; struct fid *fhp; int flags; struct vnode **vpp; { return (EOPNOTSUPP); } int vfs_stdinit (vfsp) struct vfsconf *vfsp; { return (0); } int vfs_stduninit (vfsp) struct vfsconf *vfsp; { return(0); } int vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace, attrname) struct mount *mp; int cmd; struct vnode *filename_vp; int attrnamespace; const char *attrname; { if (filename_vp != NULL) VOP_UNLOCK(filename_vp); return (EOPNOTSUPP); } int vfs_stdsysctl(mp, op, req) struct mount *mp; fsctlop_t op; struct sysctl_req *req; { return (EOPNOTSUPP); } static vop_bypass_t * bp_by_off(struct vop_vector *vop, struct vop_generic_args *a) { return (*(vop_bypass_t **)((char *)vop + a->a_desc->vdesc_vop_offset)); } int vop_sigdefer(struct vop_vector *vop, struct vop_generic_args *a) { vop_bypass_t *bp; int prev_stops, rc; bp = bp_by_off(vop, a); MPASS(bp != NULL); prev_stops = sigdeferstop(SIGDEFERSTOP_SILENT); rc = bp(a); sigallowstop(prev_stops); return (rc); } static int vop_stdstat(struct vop_stat_args *a) { struct vattr vattr; struct vattr *vap; struct vnode *vp; struct stat *sb; int error; u_short mode; vp = a->a_vp; sb = a->a_sb; error = vop_stat_helper_pre(a); if (error != 0) return (error); vap = &vattr; /* * Initialize defaults for new and unusual fields, so that file * systems which don't support these fields don't need to know * about them. */ vap->va_birthtime.tv_sec = -1; vap->va_birthtime.tv_nsec = 0; vap->va_fsid = VNOVAL; vap->va_gen = 0; vap->va_rdev = NODEV; error = VOP_GETATTR(vp, vap, a->a_active_cred); if (error) goto out; /* * Zero the spare stat fields */ bzero(sb, sizeof *sb); /* * Copy from vattr table */ if (vap->va_fsid != VNOVAL) sb->st_dev = vap->va_fsid; else sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; sb->st_ino = vap->va_fileid; mode = vap->va_mode; switch (vap->va_type) { case VREG: mode |= S_IFREG; break; case VDIR: mode |= S_IFDIR; break; case VBLK: mode |= S_IFBLK; break; case VCHR: mode |= S_IFCHR; break; case VLNK: mode |= S_IFLNK; break; case VSOCK: mode |= S_IFSOCK; break; case VFIFO: mode |= S_IFIFO; break; default: error = EBADF; goto out; } sb->st_mode = mode; sb->st_nlink = vap->va_nlink; sb->st_uid = vap->va_uid; sb->st_gid = vap->va_gid; sb->st_rdev = vap->va_rdev; if (vap->va_size > OFF_MAX) { error = EOVERFLOW; goto out; } sb->st_size = vap->va_size; sb->st_atim.tv_sec = vap->va_atime.tv_sec; sb->st_atim.tv_nsec = vap->va_atime.tv_nsec; sb->st_mtim.tv_sec = vap->va_mtime.tv_sec; sb->st_mtim.tv_nsec = vap->va_mtime.tv_nsec; sb->st_ctim.tv_sec = vap->va_ctime.tv_sec; sb->st_ctim.tv_nsec = vap->va_ctime.tv_nsec; sb->st_birthtim.tv_sec = vap->va_birthtime.tv_sec; sb->st_birthtim.tv_nsec = vap->va_birthtime.tv_nsec; /* * According to www.opengroup.org, the meaning of st_blksize is * "a filesystem-specific preferred I/O block size for this * object. In some filesystem types, this may vary from file * to file" * Use minimum/default of PAGE_SIZE (e.g. for VCHR). */ sb->st_blksize = max(PAGE_SIZE, vap->va_blocksize); sb->st_flags = vap->va_flags; sb->st_blocks = vap->va_bytes / S_BLKSIZE; sb->st_gen = vap->va_gen; out: return (vop_stat_helper_post(a, error)); } static int vop_stdread_pgcache(struct vop_read_pgcache_args *ap __unused) { return (EJUSTRETURN); } static int vop_stdvput_pair(struct vop_vput_pair_args *ap) { struct vnode *dvp, *vp, **vpp; dvp = ap->a_dvp; vpp = ap->a_vpp; vput(dvp); if (vpp != NULL && ap->a_unlock_vp && (vp = *vpp) != NULL) vput(vp); return (0); }