[POWERPC] spufs: Fix bitrot of the SPU mmap facility

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>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Benjamin Herrenschmidt 2007-02-13 11:46:08 +11:00 committed by Paul Mackerras
parent 44430e0d39
commit 17e0e27020
3 changed files with 22 additions and 8 deletions

View File

@ -111,13 +111,17 @@ void spu_unmap_mappings(struct spu_context *ctx)
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)

View File

@ -45,8 +45,8 @@ spufs_mem_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 = 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 *inode, struct file *file)
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 inode *inode, struct file *file)
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 inode *inode, struct file *file)
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 *file, struct vm_area_struct *vma)
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 *file, struct vm_area_struct *vma)
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 *inode, struct file *file)
return -EBUSY;
file->private_data = ctx;
ctx->mfc = inode->i_mapping;
smp_wmb();
return nonseekable_open(inode, file);
}

View File

@ -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;