From c6730ed4c280ff9e55766796523c94a7d111da09 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Mon, 20 Nov 2006 18:45:10 +0100 Subject: [PATCH] [POWERPC] spufs: Load isolation kernel from spu_run In order to fit with the "don't-run-spus-outside-of-spu_run" model, this patch starts the isolated-mode loader in spu_run, rather than spu_create. If spu_run is passed an isolated-mode context that isn't in isolated mode state, it will run the loader. This fixes potential races with the isolated SPE app doing a stop-and-signal before the PPE has called spu_run: bugzilla #29111. Also (in conjunction with a mambo patch), this addresses #28565, as we always set the runcntrl register when entering spu_run. It is up to libspe to ensure that isolated-mode apps are cleaned up after running to completion - ie, put the app through the "ISOLATE EXIT" state (see Ch11 of the CBEA). Signed-off-by: Jeremy Kerr Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/cell/spufs/file.c | 32 -------- arch/powerpc/platforms/cell/spufs/inode.c | 109 +--------------------------- arch/powerpc/platforms/cell/spufs/run.c | 117 ++++++++++++++++++++++++++++-- arch/powerpc/platforms/cell/spufs/spufs.h | 3 +- 4 files changed, 113 insertions(+), 148 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c index e666753..50e0afc 100644 --- a/arch/powerpc/platforms/cell/spufs/file.c +++ b/arch/powerpc/platforms/cell/spufs/file.c @@ -1358,37 +1358,6 @@ static struct file_operations spufs_mfc_fops = { .mmap = spufs_mfc_mmap, }; - -static int spufs_recycle_open(struct inode *inode, struct file *file) -{ - file->private_data = SPUFS_I(inode)->i_ctx; - return nonseekable_open(inode, file); -} - -static ssize_t spufs_recycle_write(struct file *file, - const char __user *buffer, size_t size, loff_t *pos) -{ - struct spu_context *ctx = file->private_data; - int ret; - - if (!(ctx->flags & SPU_CREATE_ISOLATE)) - return -EINVAL; - - if (size < 1) - return -EINVAL; - - ret = spu_recycle_isolated(ctx); - - if (ret) - return ret; - return size; -} - -static struct file_operations spufs_recycle_fops = { - .open = spufs_recycle_open, - .write = spufs_recycle_write, -}; - static void spufs_npc_set(void *data, u64 val) { struct spu_context *ctx = data; @@ -1789,6 +1758,5 @@ struct tree_descr spufs_dir_nosched_contents[] = { { "psmap", &spufs_psmap_fops, 0666, }, { "phys-id", &spufs_id_ops, 0666, }, { "object-id", &spufs_object_id_ops, 0666, }, - { "recycle", &spufs_recycle_fops, 0222, }, {}, }; diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c index 1fbcc53..d5f0a21 100644 --- a/arch/powerpc/platforms/cell/spufs/inode.c +++ b/arch/powerpc/platforms/cell/spufs/inode.c @@ -34,8 +34,6 @@ #include #include -#include -#include #include #include #include @@ -43,7 +41,7 @@ #include "spufs.h" static kmem_cache_t *spufs_inode_cache; -static char *isolated_loader; +char *isolated_loader; static struct inode * spufs_alloc_inode(struct super_block *sb) @@ -235,102 +233,6 @@ struct file_operations spufs_context_fops = { .fsync = simple_sync_file, }; -static int spu_setup_isolated(struct spu_context *ctx) -{ - int ret; - u64 __iomem *mfc_cntl; - u64 sr1; - u32 status; - unsigned long timeout; - const u32 status_loading = SPU_STATUS_RUNNING - | SPU_STATUS_ISOLATED_STATE | SPU_STATUS_ISOLATED_LOAD_STATUS; - - if (!isolated_loader) - return -ENODEV; - - /* prevent concurrent operation with spu_run */ - down(&ctx->run_sema); - ctx->ops->master_start(ctx); - - ret = spu_acquire_exclusive(ctx); - if (ret) - goto out; - - mfc_cntl = &ctx->spu->priv2->mfc_control_RW; - - /* purge the MFC DMA queue to ensure no spurious accesses before we - * enter kernel mode */ - timeout = jiffies + HZ; - out_be64(mfc_cntl, MFC_CNTL_PURGE_DMA_REQUEST); - while ((in_be64(mfc_cntl) & MFC_CNTL_PURGE_DMA_STATUS_MASK) - != MFC_CNTL_PURGE_DMA_COMPLETE) { - if (time_after(jiffies, timeout)) { - printk(KERN_ERR "%s: timeout flushing MFC DMA queue\n", - __FUNCTION__); - ret = -EIO; - goto out_unlock; - } - cond_resched(); - } - - /* put the SPE in kernel mode to allow access to the loader */ - sr1 = spu_mfc_sr1_get(ctx->spu); - sr1 &= ~MFC_STATE1_PROBLEM_STATE_MASK; - spu_mfc_sr1_set(ctx->spu, sr1); - - /* start the loader */ - ctx->ops->signal1_write(ctx, (unsigned long)isolated_loader >> 32); - ctx->ops->signal2_write(ctx, - (unsigned long)isolated_loader & 0xffffffff); - - ctx->ops->runcntl_write(ctx, - SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE); - - ret = 0; - timeout = jiffies + HZ; - while (((status = ctx->ops->status_read(ctx)) & status_loading) == - status_loading) { - if (time_after(jiffies, timeout)) { - printk(KERN_ERR "%s: timeout waiting for loader\n", - __FUNCTION__); - ret = -EIO; - goto out_drop_priv; - } - cond_resched(); - } - - if (!(status & SPU_STATUS_RUNNING)) { - /* If isolated LOAD has failed: run SPU, we will get a stop-and - * signal later. */ - pr_debug("%s: isolated LOAD failed\n", __FUNCTION__); - ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE); - ret = -EACCES; - - } else if (!(status & SPU_STATUS_ISOLATED_STATE)) { - /* This isn't allowed by the CBEA, but check anyway */ - pr_debug("%s: SPU fell out of isolated mode?\n", __FUNCTION__); - ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP); - ret = -EINVAL; - } - -out_drop_priv: - /* Finished accessing the loader. Drop kernel mode */ - sr1 |= MFC_STATE1_PROBLEM_STATE_MASK; - spu_mfc_sr1_set(ctx->spu, sr1); - -out_unlock: - spu_release_exclusive(ctx); -out: - ctx->ops->master_stop(ctx); - up(&ctx->run_sema); - return ret; -} - -int spu_recycle_isolated(struct spu_context *ctx) -{ - return spu_setup_isolated(ctx); -} - static int spufs_mkdir(struct inode *dir, struct dentry *dentry, unsigned int flags, int mode) @@ -439,15 +341,6 @@ static int spufs_create_context(struct inode *inode, out_unlock: mutex_unlock(&inode->i_mutex); out: - if (ret >= 0 && (flags & SPU_CREATE_ISOLATE)) { - int setup_err = spu_setup_isolated( - SPUFS_I(dentry->d_inode)->i_ctx); - /* FIXME: clean up context again on failure to avoid - leak. */ - if (setup_err) - ret = setup_err; - } - dput(dentry); return ret; } diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c index 212b9c2..1be4e33 100644 --- a/arch/powerpc/platforms/cell/spufs/run.c +++ b/arch/powerpc/platforms/cell/spufs/run.c @@ -4,6 +4,8 @@ #include #include +#include +#include #include #include "spufs.h" @@ -51,21 +53,122 @@ static inline int spu_stopped(struct spu_context *ctx, u32 * stat) return (!(*stat & 0x1) || pte_fault || spu->class_0_pending) ? 1 : 0; } +static int spu_setup_isolated(struct spu_context *ctx) +{ + int ret; + u64 __iomem *mfc_cntl; + u64 sr1; + u32 status; + unsigned long timeout; + const u32 status_loading = SPU_STATUS_RUNNING + | SPU_STATUS_ISOLATED_STATE | SPU_STATUS_ISOLATED_LOAD_STATUS; + + if (!isolated_loader) + return -ENODEV; + + ret = spu_acquire_exclusive(ctx); + if (ret) + goto out; + + mfc_cntl = &ctx->spu->priv2->mfc_control_RW; + + /* purge the MFC DMA queue to ensure no spurious accesses before we + * enter kernel mode */ + timeout = jiffies + HZ; + out_be64(mfc_cntl, MFC_CNTL_PURGE_DMA_REQUEST); + while ((in_be64(mfc_cntl) & MFC_CNTL_PURGE_DMA_STATUS_MASK) + != MFC_CNTL_PURGE_DMA_COMPLETE) { + if (time_after(jiffies, timeout)) { + printk(KERN_ERR "%s: timeout flushing MFC DMA queue\n", + __FUNCTION__); + ret = -EIO; + goto out_unlock; + } + cond_resched(); + } + + /* put the SPE in kernel mode to allow access to the loader */ + sr1 = spu_mfc_sr1_get(ctx->spu); + sr1 &= ~MFC_STATE1_PROBLEM_STATE_MASK; + spu_mfc_sr1_set(ctx->spu, sr1); + + /* start the loader */ + ctx->ops->signal1_write(ctx, (unsigned long)isolated_loader >> 32); + ctx->ops->signal2_write(ctx, + (unsigned long)isolated_loader & 0xffffffff); + + ctx->ops->runcntl_write(ctx, + SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE); + + ret = 0; + timeout = jiffies + HZ; + while (((status = ctx->ops->status_read(ctx)) & status_loading) == + status_loading) { + if (time_after(jiffies, timeout)) { + printk(KERN_ERR "%s: timeout waiting for loader\n", + __FUNCTION__); + ret = -EIO; + goto out_drop_priv; + } + cond_resched(); + } + + if (!(status & SPU_STATUS_RUNNING)) { + /* If isolated LOAD has failed: run SPU, we will get a stop-and + * signal later. */ + pr_debug("%s: isolated LOAD failed\n", __FUNCTION__); + ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_RUNNABLE); + ret = -EACCES; + + } else if (!(status & SPU_STATUS_ISOLATED_STATE)) { + /* This isn't allowed by the CBEA, but check anyway */ + pr_debug("%s: SPU fell out of isolated mode?\n", __FUNCTION__); + ctx->ops->runcntl_write(ctx, SPU_RUNCNTL_STOP); + ret = -EINVAL; + } + +out_drop_priv: + /* Finished accessing the loader. Drop kernel mode */ + sr1 |= MFC_STATE1_PROBLEM_STATE_MASK; + spu_mfc_sr1_set(ctx->spu, sr1); + +out_unlock: + spu_release_exclusive(ctx); +out: + return ret; +} + static inline int spu_run_init(struct spu_context *ctx, u32 * npc) { int ret; unsigned long runcntl = SPU_RUNCNTL_RUNNABLE; - if ((ret = spu_acquire_runnable(ctx)) != 0) + ret = spu_acquire_runnable(ctx); + if (ret) return ret; - /* if we're in isolated mode, we would have started the SPU - * earlier, so don't do it again now. */ - if (!(ctx->flags & SPU_CREATE_ISOLATE)) { + if (ctx->flags & SPU_CREATE_ISOLATE) { + if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) { + /* Need to release ctx, because spu_setup_isolated will + * acquire it exclusively. + */ + spu_release(ctx); + ret = spu_setup_isolated(ctx); + if (!ret) + ret = spu_acquire_runnable(ctx); + } + + /* if userspace has set the runcntrl register (eg, to issue an + * isolated exit), we need to re-set it here */ + runcntl = ctx->ops->runcntl_read(ctx) & + (SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE); + if (runcntl == 0) + runcntl = SPU_RUNCNTL_RUNNABLE; + } else ctx->ops->npc_write(ctx, *npc); - ctx->ops->runcntl_write(ctx, runcntl); - } - return 0; + + ctx->ops->runcntl_write(ctx, runcntl); + return ret; } static inline int spu_run_fini(struct spu_context *ctx, u32 * npc, diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h index ca56b9b..23d20f3 100644 --- a/arch/powerpc/platforms/cell/spufs/spufs.h +++ b/arch/powerpc/platforms/cell/spufs/spufs.h @@ -183,7 +183,8 @@ void spu_yield(struct spu_context *ctx); int __init spu_sched_init(void); void __exit spu_sched_exit(void); -int spu_recycle_isolated(struct spu_context *ctx); +extern char *isolated_loader; + /* * spufs_wait * Same as wait_event_interruptible(), except that here -- 2.7.4