From: Benjamin Herrenschmidt <benh@kernel•crashing.org>
To: Paul Mackerras <paulus@samba•org>
Cc: linuxppc-dev@ozlabs•org, cbe-oss-dev@ozlabs•org
Subject: [PATCH 3/3] spufs: Fix bitrot of the SPU mmap facility
Date: Tue, 13 Feb 2007 11:46:08 +1100 [thread overview]
Message-ID: <20070213004618.82B78DDEE2@ozlabs.org> (raw)
In-Reply-To: <1171327564.314011.545768742379.qpush@grosgo>
It looks like we've had some serious bitrot there mostly due to tracking
of address_space's of mmap'ed files getting out of sync with the actual
mmap code. The mfc, mss and psmap were not tracked properly and thus
not invalidated on context switches (oops !)
I also removed the various file->f_mapping = inode->i_mapping;
assignments that were done in the other open() routines since that
is already done for us by __dentry_open.
One improvement we might want to do later is to assign the various
ctx-> fields at mmap time instead of file open/close time so that we
don't call unmap_mapping_range() on thing that have not been mmap'ed
Finally, I added some smp_wmb's after assigning the ctx-> fields to make
sure they are visible to other CPUs. I don't think this is really
necessary as I suspect locking in the fs layer will make that happen
anyway but better safe than sorry.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel•crashing.org>
arch/powerpc/platforms/cell/spufs/context.c | 12 ++++++++----
arch/powerpc/platforms/cell/spufs/file.c | 16 ++++++++++++----
arch/powerpc/platforms/cell/spufs/spufs.h | 2 ++
3 files changed, 22 insertions(+), 8 deletions(-)
Index: linux-cell/arch/powerpc/platforms/cell/spufs/context.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/context.c 2007-02-09 15:47:28.000000000 +1100
+++ linux-cell/arch/powerpc/platforms/cell/spufs/context.c 2007-02-09 15:48:27.000000000 +1100
@@ -111,13 +111,17 @@ void spu_unmap_mappings(struct spu_conte
if (ctx->local_store)
unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
if (ctx->mfc)
- unmap_mapping_range(ctx->mfc, 0, 0x4000, 1);
+ unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
if (ctx->cntl)
- unmap_mapping_range(ctx->cntl, 0, 0x4000, 1);
+ unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
if (ctx->signal1)
- unmap_mapping_range(ctx->signal1, 0, 0x4000, 1);
+ unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
if (ctx->signal2)
- unmap_mapping_range(ctx->signal2, 0, 0x4000, 1);
+ unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
+ if (ctx->mss)
+ unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
+ if (ctx->psmap)
+ unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
}
int spu_acquire_exclusive(struct spu_context *ctx)
Index: linux-cell/arch/powerpc/platforms/cell/spufs/file.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/file.c 2007-02-09 15:47:28.000000000 +1100
+++ linux-cell/arch/powerpc/platforms/cell/spufs/file.c 2007-02-09 16:29:33.000000000 +1100
@@ -45,8 +45,8 @@ spufs_mem_open(struct inode *inode, stru
struct spufs_inode_info *i = SPUFS_I(inode);
struct spu_context *ctx = i->i_ctx;
file->private_data = ctx;
- file->f_mapping = inode->i_mapping;
ctx->local_store = inode->i_mapping;
+ smp_wmb();
return 0;
}
@@ -232,8 +232,8 @@ static int spufs_cntl_open(struct inode
struct spu_context *ctx = i->i_ctx;
file->private_data = ctx;
- file->f_mapping = inode->i_mapping;
ctx->cntl = inode->i_mapping;
+ smp_wmb();
return simple_attr_open(inode, file, spufs_cntl_get,
spufs_cntl_set, "0x%08lx");
}
@@ -717,8 +717,8 @@ static int spufs_signal1_open(struct ino
struct spufs_inode_info *i = SPUFS_I(inode);
struct spu_context *ctx = i->i_ctx;
file->private_data = ctx;
- file->f_mapping = inode->i_mapping;
ctx->signal1 = inode->i_mapping;
+ smp_wmb();
return nonseekable_open(inode, file);
}
@@ -824,8 +824,8 @@ static int spufs_signal2_open(struct ino
struct spufs_inode_info *i = SPUFS_I(inode);
struct spu_context *ctx = i->i_ctx;
file->private_data = ctx;
- file->f_mapping = inode->i_mapping;
ctx->signal2 = inode->i_mapping;
+ smp_wmb();
return nonseekable_open(inode, file);
}
@@ -1021,8 +1021,11 @@ static int spufs_mss_mmap(struct file *f
static int spufs_mss_open(struct inode *inode, struct file *file)
{
struct spufs_inode_info *i = SPUFS_I(inode);
+ struct spu_context *ctx = i->i_ctx;
file->private_data = i->i_ctx;
+ ctx->mss = inode->i_mapping;
+ smp_wmb();
return nonseekable_open(inode, file);
}
@@ -1060,8 +1063,11 @@ static int spufs_psmap_mmap(struct file
static int spufs_psmap_open(struct inode *inode, struct file *file)
{
struct spufs_inode_info *i = SPUFS_I(inode);
+ struct spu_context *ctx = i->i_ctx;
file->private_data = i->i_ctx;
+ ctx->psmap = inode->i_mapping;
+ smp_wmb();
return nonseekable_open(inode, file);
}
@@ -1114,6 +1120,8 @@ static int spufs_mfc_open(struct inode *
return -EBUSY;
file->private_data = ctx;
+ ctx->mfc = inode->i_mapping;
+ smp_wmb();
return nonseekable_open(inode, file);
}
Index: linux-cell/arch/powerpc/platforms/cell/spufs/spufs.h
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/spufs.h 2007-02-09 15:47:28.000000000 +1100
+++ linux-cell/arch/powerpc/platforms/cell/spufs/spufs.h 2007-02-09 15:48:15.000000000 +1100
@@ -51,6 +51,8 @@ struct spu_context {
struct address_space *cntl; /* 'control' area mappings. */
struct address_space *signal1; /* 'signal1' area mappings. */
struct address_space *signal2; /* 'signal2' area mappings. */
+ struct address_space *mss; /* 'mss' area mappings. */
+ struct address_space *psmap; /* 'psmap' area mappings. */
u64 object_id; /* user space pointer for oprofile */
enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
next prev parent reply other threads:[~2007-02-13 0:46 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-02-13 0:46 [PATCH 0/3] spufs: mmap fixes and updates Benjamin Herrenschmidt
2007-02-13 0:46 ` [PATCH 1/3] spufs: remove need for struct page for SPEs Benjamin Herrenschmidt
2007-02-13 12:15 ` [Cbe-oss-dev] " Arnd Bergmann
2007-02-13 0:46 ` [PATCH 2/3] powerpc: Remove SPU struct page's for PS3 Benjamin Herrenschmidt
2007-02-13 12:16 ` [Cbe-oss-dev] " Arnd Bergmann
2007-02-13 0:46 ` Benjamin Herrenschmidt [this message]
2007-02-13 12:16 ` [Cbe-oss-dev] [PATCH 3/3] spufs: Fix bitrot of the SPU mmap facility Arnd Bergmann
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