| Message ID | 20240912131729.14951-2-yi.l.liu@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | vfio-pci support pasid attach/detach | expand |
On 2024/9/12 23:11, Matthew Wilcox wrote: > On Thu, Sep 12, 2024 at 06:17:26AM -0700, Yi Liu wrote: >> There is no helpers for user to check if a given ID is allocated or not, >> neither a helper to loop all the allocated IDs in an IDA and do something >> for cleanup. With the two needs, a helper to get the lowest allocated ID >> of a range and two variants based on it. >> >> Caller can check if a given ID is allocated or not by: >> >> bool ida_exists(struct ida *ida, unsigned int id) >> >> Caller can iterate all allocated IDs by: >> >> int id; >> while ((id = ida_find_first(&pasid_ida)) > 0) { >> //anything to do with the allocated ID >> ida_free(pasid_ida, pasid); >> } >> >> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> >> Suggested-by: Jason Gunthorpe <jgg@nvidia.com> >> Signed-off-by: Yi Liu <yi.l.liu@intel.com> >> --- >> include/linux/idr.h | 11 ++++++++ >> lib/idr.c | 67 +++++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 78 insertions(+) > > No test cases for the test suite? ;-( let me add something like the below. :) diff --git a/lib/test_ida.c b/lib/test_ida.c index c80155a1956d..d89554ff5719 100644 --- a/lib/test_ida.c +++ b/lib/test_ida.c @@ -189,6 +189,75 @@ static void ida_check_bad_free(struct ida *ida) IDA_BUG_ON(ida, !ida_is_empty(ida)); } +/* + * Check ida_find_first_range() and varriants. + */ +static void ida_check_find_first(struct ida *ida) +{ + /* IDA is empty; all of the below should be not exist */ + IDA_BUG_ON(ida, ida_exists(ida, 0)); + IDA_BUG_ON(ida, ida_exists(ida, 3)); + IDA_BUG_ON(ida, ida_exists(ida, 63)); + IDA_BUG_ON(ida, ida_exists(ida, 1023)); + IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1)); + /* IDA contains a single value entry */ + + IDA_BUG_ON(ida, ida_alloc_min(ida, 3, GFP_KERNEL) != 3); + IDA_BUG_ON(ida, ida_exists(ida, 0)); + IDA_BUG_ON(ida, !ida_exists(ida, 3)); + IDA_BUG_ON(ida, ida_exists(ida, 63)); + IDA_BUG_ON(ida, ida_exists(ida, 1023)); + IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1)); + + IDA_BUG_ON(ida, ida_alloc_min(ida, 63, GFP_KERNEL) != 63); + IDA_BUG_ON(ida, ida_exists(ida, 0)); + IDA_BUG_ON(ida, !ida_exists(ida, 3)); + IDA_BUG_ON(ida, !ida_exists(ida, 63)); + IDA_BUG_ON(ida, ida_exists(ida, 1023)); + IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1)); + + /* IDA contains a single bitmap */ + IDA_BUG_ON(ida, ida_alloc_min(ida, 1023, GFP_KERNEL) != 1023); + IDA_BUG_ON(ida, ida_exists(ida, 0)); + IDA_BUG_ON(ida, !ida_exists(ida, 3)); + IDA_BUG_ON(ida, !ida_exists(ida, 63)); + IDA_BUG_ON(ida, !ida_exists(ida, 1023)); + IDA_BUG_ON(ida, ida_exists(ida, (1 << 20) - 1)); + + /* IDA contains a tree */ + IDA_BUG_ON(ida, ida_alloc_min(ida, (1 << 20) - 1, GFP_KERNEL) != (1 << 20) - 1); + IDA_BUG_ON(ida, ida_exists(ida, 0)); + IDA_BUG_ON(ida, !ida_exists(ida, 3)); + IDA_BUG_ON(ida, !ida_exists(ida, 63)); + IDA_BUG_ON(ida, !ida_exists(ida, 1023)); + IDA_BUG_ON(ida, !ida_exists(ida, (1 << 20) - 1)); + + /* Now try to find first */ + IDA_BUG_ON(ida, ida_find_first(ida) != 3); + IDA_BUG_ON(ida, ida_find_first_range(ida, -1, 2) != -EINVAL); + IDA_BUG_ON(ida, ida_find_first_range(ida, 0, 2) != -ENOENT); // no used ID + IDA_BUG_ON(ida, ida_find_first_range(ida, 0, 3) != 3); + IDA_BUG_ON(ida, ida_find_first_range(ida, 1, 3) != 3); + IDA_BUG_ON(ida, ida_find_first_range(ida, 3, 3) != 3); + IDA_BUG_ON(ida, ida_find_first_range(ida, 2, 4) != 3); + IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 3) != -ENOENT); // min > max, fail + IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 60) != -ENOENT); // no used ID + IDA_BUG_ON(ida, ida_find_first_range(ida, 4, 64) != 63); + IDA_BUG_ON(ida, ida_find_first_range(ida, 63, 63) != 63); + IDA_BUG_ON(ida, ida_find_first_range(ida, 64, 1026) != 1023); + IDA_BUG_ON(ida, ida_find_first_range(ida, 1023, 1023) != 1023); + IDA_BUG_ON(ida, ida_find_first_range(ida, 1023, (1 << 20) - 1) != 1023); + IDA_BUG_ON(ida, ida_find_first_range(ida, 1024, (1 << 20) - 1) != (1 << 20) - 1); + IDA_BUG_ON(ida, ida_find_first_range(ida, (1 << 20), INT_MAX) != -ENOENT); + + ida_free(ida, 3); + ida_free(ida, 63); + ida_free(ida, 1023); + ida_free(ida, (1 << 20) - 1); + + IDA_BUG_ON(ida, !ida_is_empty(ida)); +} + static DEFINE_IDA(ida); static int ida_checks(void) @@ -202,6 +270,7 @@ static int ida_checks(void) ida_check_max(&ida); ida_check_conv(&ida); ida_check_bad_free(&ida); + ida_check_find_first(&ida); printk("IDA: %u of %u tests passed\n", tests_passed, tests_run); return (tests_run != tests_passed) ? 0 : -EINVAL;
On Fri, Sep 13, 2024 at 07:45:55PM +0800, Yi Liu wrote: > > No test cases for the test suite? ;-( > > let me add something like the below. :) That looks pretty comprehensive, thanks! Acked-by: Matthew Wilcox (Oracle) <willy@infradead.org>
On 2024/9/13 23:09, Matthew Wilcox wrote: > On Fri, Sep 13, 2024 at 07:45:55PM +0800, Yi Liu wrote: >>> No test cases for the test suite? ;-( >> >> let me add something like the below. :) > > That looks pretty comprehensive, thanks! > > Acked-by: Matthew Wilcox (Oracle) <willy@infradead.org> thanks, and FYI. I found a bug when running the unit test. will fix it in the next version. it's really helpful suggestion. diff --git a/lib/idr.c b/lib/idr.c index 6644d3d1af02..f16eb3d172bc 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -494,6 +494,7 @@ int ida_find_first_range(struct ida *ida, unsigned int min, unsigned int max) unsigned int offset = min % IDA_BITMAP_BITS; unsigned long *addr, size, bit; unsigned long flags; + unsigned long tmp = 0; void *entry; int ret; @@ -518,8 +519,7 @@ int ida_find_first_range(struct ida *ida, unsigned int min, unsigned int max) } if (xa_is_value(entry)) { - unsigned long tmp = xa_to_value(entry); - + tmp = xa_to_value(entry); addr = &tmp; size = BITS_PER_XA_VALUE; } else {
diff --git a/include/linux/idr.h b/include/linux/idr.h index da5f5fa4a3a6..718f9b1b91af 100644 --- a/include/linux/idr.h +++ b/include/linux/idr.h @@ -257,6 +257,7 @@ struct ida { int ida_alloc_range(struct ida *, unsigned int min, unsigned int max, gfp_t); void ida_free(struct ida *, unsigned int id); void ida_destroy(struct ida *ida); +int ida_find_first_range(struct ida *ida, unsigned int min, unsigned int max); /** * ida_alloc() - Allocate an unused ID. @@ -328,4 +329,14 @@ static inline bool ida_is_empty(const struct ida *ida) { return xa_empty(&ida->xa); } + +static inline bool ida_exists(struct ida *ida, unsigned int id) +{ + return ida_find_first_range(ida, id, id) == id; +} + +static inline int ida_find_first(struct ida *ida) +{ + return ida_find_first_range(ida, 0, ~0); +} #endif /* __IDR_H__ */ diff --git a/lib/idr.c b/lib/idr.c index da36054c3ca0..6644d3d1af02 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -476,6 +476,73 @@ int ida_alloc_range(struct ida *ida, unsigned int min, unsigned int max, } EXPORT_SYMBOL(ida_alloc_range); +/** + * ida_find_first_range - Get the lowest used ID. + * @ida: IDA handle. + * @min: Lowest ID to get. + * @max: Highest ID to get. + * + * Get the lowest used ID between @min and @max, inclusive. The returned + * ID will not exceed %INT_MAX, even if @max is larger. + * + * Context: Any context. Takes and releases the xa_lock. + * Return: The lowest used ID, or errno if no used ID is found. + */ +int ida_find_first_range(struct ida *ida, unsigned int min, unsigned int max) +{ + unsigned long index = min / IDA_BITMAP_BITS; + unsigned int offset = min % IDA_BITMAP_BITS; + unsigned long *addr, size, bit; + unsigned long flags; + void *entry; + int ret; + + if ((int)min < 0) + return -EINVAL; + if ((int)max < 0) + max = INT_MAX; + + xa_lock_irqsave(&ida->xa, flags); + + entry = xa_find(&ida->xa, &index, max / IDA_BITMAP_BITS, XA_PRESENT); + if (!entry) { + ret = -ENOENT; + goto err_unlock; + } + + if (index > min / IDA_BITMAP_BITS) + offset = 0; + if (index * IDA_BITMAP_BITS + offset > max) { + ret = -ENOENT; + goto err_unlock; + } + + if (xa_is_value(entry)) { + unsigned long tmp = xa_to_value(entry); + + addr = &tmp; + size = BITS_PER_XA_VALUE; + } else { + addr = ((struct ida_bitmap *)entry)->bitmap; + size = IDA_BITMAP_BITS; + } + + bit = find_next_bit(addr, size, offset); + + xa_unlock_irqrestore(&ida->xa, flags); + + if (bit == size || + index * IDA_BITMAP_BITS + bit > max) + return -ENOENT; + + return index * IDA_BITMAP_BITS + bit; + +err_unlock: + xa_unlock_irqrestore(&ida->xa, flags); + return ret; +} +EXPORT_SYMBOL(ida_find_first_range); + /** * ida_free() - Release an allocated ID. * @ida: IDA handle.
There is no helpers for user to check if a given ID is allocated or not, neither a helper to loop all the allocated IDs in an IDA and do something for cleanup. With the two needs, a helper to get the lowest allocated ID of a range and two variants based on it. Caller can check if a given ID is allocated or not by: bool ida_exists(struct ida *ida, unsigned int id) Caller can iterate all allocated IDs by: int id; while ((id = ida_find_first(&pasid_ida)) > 0) { //anything to do with the allocated ID ida_free(pasid_ida, pasid); } Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Yi Liu <yi.l.liu@intel.com> --- include/linux/idr.h | 11 ++++++++ lib/idr.c | 67 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+)