From 47a2b7dc03e35d4eaf8148b87aeea8dd96723b4d Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Tue, 22 Apr 2008 16:08:23 -0700 Subject: Initial add of mmfs module. --- .gitignore | 1 + linux-core/Makefile | 3 +- linux-core/Makefile.kernel | 3 +- linux-core/mmfs.h | 176 ++++++++++++++++++++++++++ linux-core/mmfs_drv.c | 299 +++++++++++++++++++++++++++++++++++++++++++++ tests/Makefile.am | 4 +- tests/mmfs_basic.c | 68 +++++++++++ 7 files changed, 551 insertions(+), 3 deletions(-) create mode 100644 linux-core/mmfs.h create mode 100644 linux-core/mmfs_drv.c create mode 100644 tests/mmfs_basic.c diff --git a/.gitignore b/.gitignore index 0991da8c..fe64a289 100644 --- a/.gitignore +++ b/.gitignore @@ -58,6 +58,7 @@ tests/getclient tests/getstats tests/getversion tests/lock +tests/mmfs_basic tests/openclose tests/setversion tests/updatedraw diff --git a/linux-core/Makefile b/linux-core/Makefile index 3af6f370..f2d44642 100644 --- a/linux-core/Makefile +++ b/linux-core/Makefile @@ -58,7 +58,7 @@ endif # Modules for all architectures MODULE_LIST := drm.o tdfx.o r128.o radeon.o mga.o sis.o savage.o via.o \ - mach64.o nv.o nouveau.o xgi.o + mach64.o nv.o nouveau.o xgi.o mmfs.o # Modules only for ix86 architectures ifneq (,$(findstring 86,$(MACHINE))) @@ -92,6 +92,7 @@ NVHEADERS = nv_drv.h $(DRMHEADERS) FFBHEADERS = ffb_drv.h $(DRMHEADERS) NOUVEAUHEADERS = nouveau_drv.h nouveau_drm.h nouveau_reg.h $(DRMHEADERS) XGIHEADERS = xgi_cmdlist.h xgi_drv.h xgi_misc.h xgi_regs.h $(DRMHEADERS) +MMFSHEADERS = mmfs.h mmfs_priv.h PROGS = dristat drmstat diff --git a/linux-core/Makefile.kernel b/linux-core/Makefile.kernel index f012262d..093552bf 100644 --- a/linux-core/Makefile.kernel +++ b/linux-core/Makefile.kernel @@ -41,6 +41,7 @@ mach64-objs := mach64_drv.o mach64_dma.o mach64_irq.o mach64_state.o nv-objs := nv_drv.o xgi-objs := xgi_cmdlist.o xgi_drv.o xgi_fb.o xgi_misc.o xgi_pcie.o \ xgi_fence.o +mmfs-objs := mmfs_drv.o ifeq ($(CONFIG_COMPAT),y) drm-objs += drm_ioc32.o @@ -52,7 +53,7 @@ nouveau-objs += nouveau_ioc32.o xgi-objs += xgi_ioc32.o endif -obj-m += drm.o +obj-m += drm.o mmfs.o obj-$(CONFIG_DRM_TDFX) += tdfx.o obj-$(CONFIG_DRM_R128) += r128.o obj-$(CONFIG_DRM_RADEON)+= radeon.o diff --git a/linux-core/mmfs.h b/linux-core/mmfs.h new file mode 100644 index 00000000..bdc148b9 --- /dev/null +++ b/linux-core/mmfs.h @@ -0,0 +1,176 @@ +/* + * Copyright © 2008 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + * Authors: + * Eric Anholt + * + */ + +/** @file mmfs.h + * This file provides ioctl and ioctl argument definitions for using the + * mmfs device. + */ +#ifdef __KERNEL__ +#include +#include + +/** @file mmfs_priv.h + * This file provides internal structure definitions for mmfs.. + */ + +/** + * This structure defines the mmfs memory object, which will be used by the + * DRM for its buffer objects. + */ +struct mmfs_object { + /** File representing the shmem storage */ + struct file *filp; + + spinlock_t lock; + + size_t size; + /** Reference count of this object, protected by object_lock */ + int refcount; +}; + +/** + * This structure defines the process (actually per-fd) mapping of object + * handles to mmfs objects. + */ +struct mmfs_file { + /** Mapping of object handles to object pointers. */ + struct idr object_idr; + /** + * Lock for synchronization of access to object->refcount and + * object_idr. See note in mmfs_unreference_ioctl. + */ + spinlock_t delete_lock; +}; + +void mmfs_object_reference(struct mmfs_object *obj); +void mmfs_object_unreference(struct mmfs_object *obj); + +#endif /* __KERNEL__ */ + +#define MMFS_DEVICE_PATH "/dev/mmfs" +/* XXX: Choose non-experimental major */ +#define MMFS_DEVICE_MAJOR 246 + +struct mmfs_alloc_args { + /** + * Requested size for the object. + * + * The (page-aligned) allocated size for the object will be returned. + */ + uint32_t size; + /** Returned handle for the object. */ + uint32_t handle; +}; + +struct mmfs_unreference_args { + /** Handle of the object to be unreferenced. */ + uint32_t handle; +}; + +struct mmfs_link_args { + /** Handle for the object being given a name. */ + uint32_t handle; + /** Requested file name to export the object under. */ + char *name; + /** Requested file mode to export the object under. */ + mode_t mode; +}; + +struct mmfs_pread_args { + /** Handle for the object being read. */ + uint32_t handle; + /** Offset into the object to read from */ + off_t offset; + /** Length of data to read */ + size_t size; + /** Pointer to write the data into. */ + void *data; +}; + +struct mmfs_pwrite_args { + /** Handle for the object being written to. */ + uint32_t handle; + /** Offset into the object to write to */ + off_t offset; + /** Length of data to write */ + size_t size; + /** Pointer to read the data from. */ + void *data; +}; + +struct mmfs_mmap_args { + /** Handle for the object being mapped. */ + uint32_t handle; + /** Offset in the object to map. */ + off_t offset; + /** + * Length of data to map. + * + * The value will be page-aligned. + */ + size_t size; + /** Returned pointer the data was mapped at */ + void *addr; +}; + +/** + * \name Ioctls Definitions + */ +/* @{ */ + +#define MMFS_IOCTL_BASE 'm' +#define MMFS_IO(nr) _IO(MMFS_IOCTL_BASE, nr) +#define MMFS_IOR(nr,type) _IOR(MMFS_IOCTL_BASE, nr, type) +#define MMFS_IOW(nr,type) _IOW(MMFS_IOCTL_BASE, nr, type) +#define MMFS_IOWR(nr,type) _IOWR(MMFS_IOCTL_BASE, nr, type) + +/** This ioctl allocates an object and returns a handle referencing it. */ +#define MMFS_IOCTL_ALLOC MMFS_IOWR(0x00, struct mmfs_alloc_args) + +/** + * This ioctl releases the reference on the handle returned from + * MMFS_IOCTL_ALLOC. + */ +#define MMFS_IOCTL_UNREFERENCE MMFS_IOR(0x01, struct mmfs_unreference_args) + +/** + * This ioctl creates a file in the mmfs filesystem representing an object. + * + * XXX: Need a way to get handle from fd or name. + */ +#define MMFS_IOCTL_LINK MMFS_IOWR(0x02, struct mmfs_link_args) + +/** This ioctl copies data from an object into a user address. */ +#define MMFS_IOCTL_PREAD MMFS_IOWR(0x03, struct mmfs_pread_args) + +/** This ioctl copies data from a user address into an object. */ +#define MMFS_IOCTL_PWRITE MMFS_IOWR(0x04, struct mmfs_pwrite_args) + +/** This ioctl maps data from the object into the user address space. */ +#define MMFS_IOCTL_MMAP MMFS_IOWR(0x05, struct mmfs_mmap_args) + +/* }@ */ diff --git a/linux-core/mmfs_drv.c b/linux-core/mmfs_drv.c new file mode 100644 index 00000000..f4b07117 --- /dev/null +++ b/linux-core/mmfs_drv.c @@ -0,0 +1,299 @@ +/* + * Copyright © 2008 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + * Authors: + * Eric Anholt + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include "mmfs.h" + +/** @file mmfs.c + * + * This file provides the filesystem for memory manager objects used by the + * DRM. + * + * The goal is to have swap-backed object allocation managed through + * struct file. However, file descriptors as handles to a struct file have + * two major failings: + * - Process limits prevent more than 1024 or so being used at a time by + * default. + * - Inability to allocate high fds will aggravate the X Server's select() + * handling, and likely that of many GL client applications as well. + * + * This led to a plan of using our own integer IDs (called handles, following + * DRM terminology) to mimic fds, and implement the fd syscalls we need as + * ioctls. The objects themselves will still include the struct file so + * that we can transition to fds if the required kernel infrastructure shows + * up at a later data, and as our interface with shmfs for memory allocation. + */ + +static struct mmfs_object * +mmfs_object_alloc(size_t size) +{ + struct mmfs_object *obj; + + BUG_ON((size & (PAGE_SIZE - 1)) != 0); + + obj = kcalloc(1, sizeof(*obj), GFP_KERNEL); + + obj->filp = shmem_file_setup("mmfs object", size, 0); + if (IS_ERR(obj->filp)) { + kfree(obj); + return NULL; + } + + obj->refcount = 1; + + return obj; +} + +/** + * Removes the mapping from handle to filp for this object. + */ +static int +mmfs_handle_delete(struct mmfs_file *mmfs_filp, int handle) +{ + struct mmfs_object *obj; + + /* This is gross. The idr system doesn't let us try a delete and + * return an error code. It just spews if you fail at deleting. + * So, we have to grab a lock around finding the object and then + * doing the delete on it and dropping the refcount, or the user + * could race us to double-decrement the refcount and cause a + * use-after-free later. Given the frequency of our handle lookups, + * we may want to use ida for number allocation and a hash table + * for the pointers, anyway. + */ + spin_lock(&mmfs_filp->delete_lock); + + /* Check if we currently have a reference on the object */ + obj = idr_find(&mmfs_filp->object_idr, handle); + if (obj == NULL) { + spin_unlock(&mmfs_filp->delete_lock); + return -EINVAL; + } + + /* Release reference and decrement refcount. */ + idr_remove(&mmfs_filp->object_idr, handle); + mmfs_object_unreference(obj); + + spin_unlock(&mmfs_filp->delete_lock); + + return 0; +} + +/** + * Allocates a new mmfs object and returns a handle to it. + */ +static int +mmfs_alloc_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + struct mmfs_file *mmfs_filp = filp->private_data; + struct mmfs_alloc_args args; + struct mmfs_object *obj; + int handle, ret; + + if (copy_from_user(&args, (void __user *)arg, sizeof(args))) + return -EFAULT; + + /* Round requested size up to page size */ + args.size = (args.size + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1); + + /* Allocate the new object */ + obj = mmfs_object_alloc(args.size); + if (obj == NULL) + return -ENOMEM; + + /* Get the user-visible handle using idr. + * + * I'm not really sure why the idr api needs us to do this in two + * repeating steps. It handles internal locking of its data + * structure, yet insists that we keep its memory allocation step + * separate from its slot-finding step for locking purposes. + */ + do { + if (idr_pre_get(&mmfs_filp->object_idr, GFP_KERNEL) == 0) { + kfree(obj); + return -EFAULT; + } + + ret = idr_get_new(&mmfs_filp->object_idr, obj, &handle); + } while (ret == -EAGAIN); + + if (ret != 0) { + mmfs_object_unreference(obj); + return -EFAULT; + } + + args.handle = handle; + + if (copy_to_user((void __user *)arg, &args, sizeof(args))) { + mmfs_handle_delete(mmfs_filp, args.handle); + return -EFAULT; + } + + return 0; +} + +/** + * Allocates a new mmfs object and returns a handle to it. + */ +static int +mmfs_unreference_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + struct mmfs_file *mmfs_filp = filp->private_data; + struct mmfs_unreference_args args; + int ret; + + if (copy_from_user(&args, (void __user *)arg, sizeof(args))) + return -EFAULT; + + ret = mmfs_handle_delete(mmfs_filp, args.handle); + + return ret; +} + +static int +mmfs_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + + switch (cmd) { + case MMFS_IOCTL_ALLOC: + return mmfs_alloc_ioctl(inode, filp, cmd, arg); + case MMFS_IOCTL_UNREFERENCE: + return mmfs_unreference_ioctl(inode, filp, cmd, arg); + default: + return -EINVAL; + } +} + +/** + * Sets up the file private for keeping track of our mappings of handles to + * mmfs objects. + */ +int +mmfs_open(struct inode *inode, struct file *filp) +{ + struct mmfs_file *mmfs_filp; + + if (filp->f_flags & O_EXCL) + return -EBUSY; /* No exclusive opens */ + + mmfs_filp = kcalloc(1, sizeof(*mmfs_filp), GFP_KERNEL); + if (mmfs_filp == NULL) + return -ENOMEM; + filp->private_data = mmfs_filp; + + idr_init(&mmfs_filp->object_idr); + + return 0; +} + +/** Called at device close to release the file's references on objects. */ +static int +mmfs_object_release(int id, void *ptr, void *data) +{ + struct mmfs_object *obj = ptr; + + mmfs_object_unreference(obj); + + return 0; +} + +/** + * Called at close time when the filp is going away. + * + * Releases any remaining references on objects by this filp. + */ +int +mmfs_close(struct inode *inode, struct file *filp) +{ + struct mmfs_file *mmfs_filp = filp->private_data; + + idr_for_each(&mmfs_filp->object_idr, &mmfs_object_release, NULL); + + idr_destroy(&mmfs_filp->object_idr); + + kfree(mmfs_filp); + filp->private_data = NULL; + + return 0; +} + +void +mmfs_object_reference(struct mmfs_object *obj) +{ + spin_lock(&obj->lock); + obj->refcount++; + spin_unlock(&obj->lock); +} + +void +mmfs_object_unreference(struct mmfs_object *obj) +{ + spin_lock(&obj->lock); + obj->refcount--; + spin_unlock(&obj->lock); + if (obj->refcount == 0) { + fput(obj->filp); + kfree(obj); + } +} + +/** File operations structure */ +static const struct file_operations mmfs_dev_fops = { + .owner = THIS_MODULE, + .open = mmfs_open, + .release = mmfs_close, + .ioctl = mmfs_ioctl, +}; + +static int __init mmfs_init(void) +{ + int ret; + + ret = register_chrdev(MMFS_DEVICE_MAJOR, "mmfs", &mmfs_dev_fops); + if (ret != 0) + return ret; + + return 0; +} + +static void __exit mmfs_exit(void) +{ + unregister_chrdev(MMFS_DEVICE_MAJOR, "mmfs"); +} + +module_init(mmfs_init); +module_exit(mmfs_exit); +MODULE_LICENSE("GPL and additional rights"); diff --git a/tests/Makefile.am b/tests/Makefile.am index dce1754e..4a7b0119 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -1,4 +1,5 @@ AM_CFLAGS = \ + -I $(top_srcdir)/linux-core \ -I $(top_srcdir)/shared-core \ -I $(top_srcdir)/libdrm @@ -22,7 +23,8 @@ TESTS = auth \ getstats \ lock \ setversion \ - updatedraw + updatedraw \ + mmfs_basic EXTRA_PROGRAMS = $(TESTS) CLEANFILES = $(EXTRA_PROGRAMS) $(EXTRA_LTLIBRARIES) diff --git a/tests/mmfs_basic.c b/tests/mmfs_basic.c new file mode 100644 index 00000000..907dc585 --- /dev/null +++ b/tests/mmfs_basic.c @@ -0,0 +1,68 @@ +/* + * Copyright © 2008 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + * Authors: + * Eric Anholt + * + */ + +#include +#include +#include +#include +#include +#include +#include "mmfs.h" + +static void +create_mmfs_device() +{ + struct stat sb; + int ret; + + ret = stat(MMFS_DEVICE_PATH, &sb); + + if (ret == 0) + return; + + ret = mknod(MMFS_DEVICE_PATH, S_IFCHR | S_IRUSR | S_IWUSR, + makedev(MMFS_DEVICE_MAJOR, 0)); + + if (ret != 0) + errx(1, "mknod()"); +} + + +int main(int argc, char **argv) +{ + int fd; + + create_mmfs_device(); + + fd = open(MMFS_DEVICE_PATH, O_RDWR); + if (fd == -1) + errx(1, "open()"); + + close(fd); + + return 0; +} -- cgit v1.2.3